Revision+Book

Ideas, put blank notes pages after each outcome with (H 1.1)
 * Contents **

The Higher School Certificate course builds upon the Preliminary course. It examines the complexity and scientific principles of the components of agricultural production and places a greater emphasis on farm management to maximise productivity and environmental sustainability. The farm as a fundamental production unit provides a basis for analysing and addressing social, environmental and economic issues as they relate to sustainability, from both national and international perspectives. This is achieved through the farm product study. Australian agriculture faces many challenges and significant and continuous change is needed to address these challenges. New computer, satellite, robotic and biological technologies are being integrated into management systems. As farmers need to respond to changing economic, social and climatic conditions, the electives focus on innovations, issues and challenges facing Australian agriculture.
 * Agriculture Stage 6 HSC course (****120 hours indicative time)**
 * Core (80%) ** (Approximately 96 indicative hours)


 * ** Plant/Animal production (50%) **
 * // This unit will be covered in Term 4, 2011 //**
 * Soil, nutrients and water
 * Factors contributing to the degradation of soil and water
 * Sustainable resource management
 * Plant production systems
 * Constraints on plant production
 * Managing plant production
 * Animal nutrition
 * Animal growth and development
 * Animal reproduction and genetics
 * Animal pests and diseases
 * Animal ethics and welfare
 * Experimental analysis and research in plant/animal systems ||


 * Farm product study (30%) **
 * The farm as a business
 * Decision-making processes and management strategies
 * Agricultural technology
 * Marketing of a specific farm product

Choose ONE of the following electives to study.
 * Elective (20 **** %) ** (Approximately 24 indicative hours)
 * Agri-food, Fibre and Fuel Technologies
 * Climate Challenge
 * Farming for the 21st Century


 * Plant/Animal production**

Animal production is dependent on plants, which in turn are dependent on the soil and water. Farmers aim to manage the physical and biological processes in soils, plants and animals to produce agricultural products in a sustainable manner. Students examine the ways in which farmers manage and manipulate these processes and systems to maximise outputs.
 * // During the plant/Animal Production Unit you will satisfy the following HSC syllabus outcomes: //**
 * // H1.1 //** explains the influence of the physical, biological, social, historical and economic factors on sustainable agricultural production
 * // H2.1 //** describes the inputs, processes and interactions of plant production systems
 * // H2.2 //** describes the inputs, processes and interactions of animal production systems
 * // H4.1 //** justifies and applies appropriate experimental techniques, technologies, research by methods and data presentation and analysis in relation to agricultural problems and situations


 * // And you will achieve these outcomes by learning about: //**


 * Soil, nutrients and water **
 * chemical and physical characteristics of soil
 * the role of soil nutrient cycles in Australian agricultural systems including the nitrogen cycle and the carbon cycle
 * the role of microbes and invertebrates in the decomposition of organic matter
 * sources of water on a farm and water management in a farm system


 * Factors contributing to the degradation of soil and water **
 * the historical development of Australian land use practices, from Aboriginal practices to the present day
 * farming practices that have contributed to soil degradation such as salination, acidification, soil structure decline, loss of soil organic matter and erosion and the effects of these on soil and water
 * practices that have contributed to changes in water quality and availability


 * Sustainable resource management **
 * sustainable techniques to maintain and/or improve soil fertility including alternative strategies to the application of inorganic fertilisers
 * the role of individual farmers, the broader community and government in reducing the harmful environmental effects of agriculture and in conserving water, protecting waterways and managing water quality
 * tension between sustainability and short-term profitability in farming systems


 * Plant production systems **
 * process of growth and development in plants
 * processes of respiration, photosynthesis, net assimilation rate, water and nutrient uptake on the effects of plant growth
 * beneficial relationships between microbes and plants including the fixing of atmospheric nitrogen in legumes
 * the role of plant hormones on plant growth and development
 * pasture production systems

complex interaction involving problem organisms (pathogenic microbe or invertebrate), the host and the environment in plant disease
 * Constraints on plant production **
 * constraints imposed by environmental factors
 * competition in plant communities


 * Managing plant production **
 * managing the constraints on plant growth and development to maximise production
 * the interaction of genotype, environment and management
 * responsible and strategic use of chemicals
 * integrated pest management (IPM)


 * Animal nutrition **
 * ruminant and monogastric digestion
 * beneficial relationships between microbes and animals including the role of microbes in animal digestion
 * the fate of energy in animal nutrition
 * managing the nutritional requirements of monogastrics and ruminants in terms of their digestive physiology


 * Animal growth and development **
 * changes in the proportion of muscle, fat and bone during the life of an animal
 * management practices to optimise growth and development


 * Animal reproduction and genetics **
 * the role of hormones in the regulation of animal reproduction and behaviour
 * factors that limit the fertility of farm animals
 * reproductive techniques
 * breeding systems and their genetic basis to improve quality and production of animals


 * Animal pests and diseases **
 * animal disease
 * integrated pest management (IPM)


 * Animal ethics and welfare **
 * ethics, welfare and legal issues and requirements


 * Experimental analysis and research in plant/animal systems **
 * experimental design
 * the collection and analysis of data
 * the role of research

A measure of the acidity or alkalinity of the soil Soil pH is one of the most important soil properties that affects the availability of nutrients. In this pH range, nutrients are more readily available to plants, and microbial populations in the soil increase. **Microbes** convert nitrogen and sulphur to forms that plants can use. Lime also enhances the physical properties of the soil that promote water and air movement. The pH indicates the acidity or alkalinity (basic) of the soil. Different plants have differing optimum soil pH requirements. The majority of plants prefer a pH of around 6 to 7, which is very slightly acid. The soil pH is important in determining the availability of soil minerals. At pH extremes some minerals are "locked up" and cannot be used by the plants, whilst other minerals may become toxic. e.g. aluminium, iron, zinc, copper, manganese and boron become more soluble under acidic conditions and can reach toxic levels. The application of different fertilisers can affect the pH of the soil. If a soil is too acid then it can be modified by the addition of lime. If it is too alkaline then elemental sulfur may be added which is oxidised by specific soil bacteria to form sulfuric acid. Ploughing in green manure crops and animal manures also lowers soil pH. Soil pH can have an effect on microbial activity in the soil.
 * Plant/Animal production **
 * Soil Nutrients and Water **
 * Soil PH**
 * Macronutrients tend to be less available in soils with low pH.
 * Micronutrients tend to be less available in soils with high pH.
 * Lime ** can be added to the soil to make it less sour (acid) and also supplies calcium and magnesium for plants to use. Lime also raises the pH to the desired range of 6.0 to 6.5.

Is an exchange of ions between two electrolyte or between an electrolyte solution and a complex In most cases the term is used to denote the processes of purification, separation, and decontamination of aqueous and other ion-containing solutions with solid polymeric or mineralic 'ion exchangers'. In soil science, cation exchange capacity is the ion exchange capacity of soil for positively charged ions. Soils can be considered as natural weak cation exchangers.
 * Ion exchange capacity**

Carbon stored within soil. It is part of the soil organic matter (SOM), which includes other important elements such as calcium, hydrogen, oxygen, and nitrogen. Soil organic matter is made up of plant and animal materials in various stages of decay. Un-decomposed materials on the surface of the soil, such as leaf litter, are not part of the organic matter until they start to decompose. Soil organic matter is often reported in soil tests as the percentage of soil organic carbon present in the soil sample. However, although determining the amount of soil organic carbon in soil is important for understanding soil health, knowing the type of organic carbon present is also important as this can greatly impact soil productivity.
 * Soil carbon**

Nutritional status is the balance between the intake of nutrients by an organism and the expenditure of these in the processes of growth, reproduction, and health maintenance. A healthy soil will provide sufficient nutrients for both plants and soil organisms. It is not just dependent on having nutrients existing in the soil as chemical compounds, it also depends on access to those nutrients. Nutrients can be locked-away from plants and soil organisms because of various soil conditions. The conditions that can influence availability and accessibility of soil nutrients include: soil moisture content; soil porosity; soil conductivity; pH; temperature; and competitive demand between organisms.
 * Nutrient status**

Biological activity (including plant growth and development) is dependent on nutrients being readily available in the soil solution. There are 15 elements that are essential nutrients for plants.


 * Physical Characteristics of Soil **

The amount of sand, silt, clay, and organic matter in soil. The soil texture is important since it determines how much moisture the soil holds, how fast the soil drains and what nutrients are in the soil. // Measured as a percentage of sand, silt and clay. //
 * Soil Texture **

Is determined by how individual soil granules clump or bind together and aggregate, and therefore, the arrangement of soil pores between them. Soil structure has a major influence on water and air movement, biological activity, root growth and seedling emergence.
 * Soil Structure **

Soil porosity refers to that part of a soil volume that is not occupied by soil particles or organic matter. //There is a simple field method to// //measure soil porosity by counting the number of pores on a face of a clod of soil.//
 * Soil porosity **

It is defined as the mass of many particles of the material divided by the total volume they occupy. The total volume includes particle volume, inter-particle void volume and internal pore volume. // Bulk density = mass of soil/core volume //
 * Bulk density **

Dispersion occurs when a soil is sodic. When a sodic soil is wetted the clay particles are forced apart. This is generally a major cause of erosion.
 * Dispersibility **


 * 1.1 ** ** the chemical and physical characteristics of soil **


 * __ Physical: __**

__Soil Texture:__ the size of soil particles and the differentiation between sand, silt and clay in a soil.

__Soil Structure:__ The arrangement of soil particles. The basic unit of soil is termed a ‘ped’.Sandy soils have no structure (apedal/structureless). Structure influences aeration, water penetration, heat transfer, gaseous exchange rates, mechanical strength and erosion potential. Soil structure can be easily changed through mechanical working when the moisture content is too high or low.

__Soil Consistency:__ A measure of the mechanical strength based of the force necessary to break a block of soil. It depends on the moisture content of the soil. Blocks are classified as ‘pulverized’ or ‘coalesced’. The less coalesced a soil is the better it is for cultivation.


 * __ Chemistry: __**

__Sand:__ Entirely silicon dioxide, it is physically and chemically inert. It does not absorb water and warms up readily. Usually of little value as a store of plant nutrient material

__Clay:__ Clay has a negatively charged surface and having a large surface area to volume ratio, they are highly reactive in a soil. They have the ability to hold water and cement other particles together to form peds. It can also store nutrients that are held by the negative charges. Positive ions of nutrients are held very tightly at the clay surface and this bond gets weaker as it gets further away. This layer of tightly and loosely bound charged ions is called the “clay double layer”. It is the loosly bound ions that are available to plants and invertebrate organisms. The amount of exchangeable ions held by a clay, is measurable and deemed the “cation exchange capacity”. This capacity is affected by:
 * 1) the charge level on the clay mineral
 * 2) the soil pH
 * 3) the types of ions located in the double layer
 * 4) organic matter

The double layer influences the physical properties, as the larger it is the less likely clay particles will come into contact, making the soil instable due to toxic levels of nutrients. The layer is usually larger when high levels of sodium of potassium are present.

As pH increases (H+), the availability of nutrients decreases as the H+ ions replace them. Therefore the pH of the soil is a determining facto in available nutrients


 * The Nitrogen Cycle **


 * Nitrogen **

Nitrogen is one of the most important nutrients for crop growth, second only to water and is the major nutrient the producer can control. Nitrogen exists in many different chemical forms and passes around natural and agricultural ecosystems in a cycle. The various forms of nitrogen determine its availability to plants or whether nitrogen escapes and is no longer available to plants. The presence of useable nitrogen and its losses affects the sustainability of production. Mismanaged it can result in economic loss to the producer, environmental repercussions, or both.


 * How plants use Nitrogen**

Nitrogen is one of the main chemical elements required for plant growth and reproduction. Nitrogen is in chlorophyll and therefore essential for photosynthesis. It is also the basic element of plant and animal proteins, including the genetic material DNA and RNA, and is important in periods of rapid plant growth.

Plants use nitrogen by absorbing either **nitrate** or **ammonium** through the roots. Most of the nitrogen is used by the plant to produce protein (in the form of enzymes) and nucleic acids. Nitrogen is readily transported through the plant from older tissue to younger tissue. Therefore, a plant deficient in nitrogen will show yellowing in the older leaves first due to the underdevelopment or destruction of chloroplasts and an absence of the green pigmented chlorophyll. While nitrogen is a major essential element it can be a problem in some circumstances. This is particularly the case when nitrogen is leached into waterways. Nitrogen becomes a concern to drinking water quality when nitrogen in the soil is converted to the nitrate (NO3-) form. It is a concern because nitrate is very mobile and easily moves with water in the soil. The concern of nitrates and water quality is generally directed at groundwater. However, nitrates can also enter surface waters such as ponds, streams and rivers and eventually the ocean, stimulating excessive plant growth (algae, periphyton attached algae, and nuisance plants weeds). This is know as //eutrophication//. The presence of nitrates in the soil is mostly the result of natural biological processes related to the decomposition of organic matter such as plant residues and animal wastes. Nitrates can also come from rainfall and nitrogen fertilisers. Whether or not nitrates actually enter groundwater depends on underlying soil and/or bedrock conditions, as well as the depth to groundwater. If groundwater is near the surface and the soil is sandy, the potential for nitrates to enter groundwater is high. High levels of nitrates can be toxic to newborn humans and animals, causing anoxia, or internal suffocation. The most common symptom of nitrate poisoning in babies is a bluish colour to the skin, particularly around the baby's eyes and mouth. These symptoms of nitrate toxicity are commonly referred to as the //blue-baby// syndrome.

**__ Microbes and Invertebrates __**
 * Microbes and invertebrates in the decomposition of organic matter**


 * 1.1 ** ** – the complex interaction involving problem organism (pathogenic microbe or invertebrate), the host and the environment in plant and animal disease **

**__The Disease Triangle__** The disease triangle shows that each of the three factors has an affect on the others. Some may have more effect yet there is always a connection. The main point the Disease triangle shows is that is on of the factors does not exist then there will be no disease as they rely on each other in an intricate balance. Similarly, if all three are present then disease is almost unconditionally present.


 * **Host** ||


 * **Pathogen** ||


 * **Environment** ||


 * Disease**

About 60 years ago, when DDT and other organochlorine pesticides became popular in agriculture, they were considered a safe and effective way to get rid of pests. But over the years, more and more problems associated with the use of pesticides have shown up. Major problems include: The use of pesticides (both synthetic and organic) **always involves certain risks** because of their poisonous character. Who is at risk? Farmers and their family members run the highest risks. They can easily come in contact with the pesticides, for example when mixing the chemicals or when applying them to the crop. The pesticides that were sprayed on the crop can leave behind residues that will be eaten by the consumers. Pesticides will not only reach the target organisms but will also kill other organisms (e.g. beneficial insects, birds, earthworms, fish) in or around the crop fields, causing loss of biodiversity, deaths of wild life, and death of farm animals. Soil, air and water bodies can easily be contaminated with these poisonous chemicals. The unavoidable destruction of beneficial insects and spiders interferes with natural pest control. The mentioned risks are most obvious when pesticides cause __acute toxicity__ to man, domestic animals and non-target organisms such as fish, bees, birds and soil organisms. The more subtle __long-term chronic effects__ (disruption of endocrine system, cancer, sterility and mutagenic effects) often go unnoticed and are not yet fully understood. Also in the environment, some pesticides have not only acute effects but also long-term effects. Especially the "persistent organic pollutants" (POPs) will continue to poison non-target organisms in the environment and will also appear as crop residues long after their use has ceased. No pesticide, synthetic or organic, is considered "safe". However, some are less dangerous to use than others, depending on their effect on living organisms. Before using a pesticide, it is essential to be well informed about the various effects it may have. Farmers have to know how to reduce the risks. Pesticides kill not only the pests but also the natural enemies of these pests. That means that natural control mechanisms are disrupted and it allows the pest populations to rapidly build up again to levels that can cause serious crop damage. The disruption of natural control can even create new pest problems. Minor pests that are usually kept at low numbers by their natural enemies will multiply rapidly in the absence of their enemies and cause outbreaks. So the control directed against one pests may result in the outbreak of another pest.
 * 1.2 ** ** – the problems of pesticides and chemical resistance in target organisms **
 * Problems associated with pesticides**
 * //Toxicity for non-target organisms//**
 * __The users of pesticides__**
 * __The consumers of farm products.__**
 * __The environment.__**
 * //Resurgence//**

The resurgence of pest populations after removing natural enemies creates a dependence on pesticides, which obviously is not sustainable. A key element of Integrated Pest Management is therefore to avoid resurgence. Conservation of natural enemies is required so that natural control will not be disrupted. One of the first discovered problems of pesticides was that pests can become resistant to the chemicals. Unaware of how to deal with this issue, farmers then decide to spray more frequently and to apply higher doses. This just causes more problems. Within a pest population there is genetic variation in their resistance to pesticides. If pests have not been previously exposed to a new pesticide, most individuals in the population are susceptible, but some individuals are resistant. Pesticides that are used to control the pest will kill most of the susceptible individuals, but the few resistant individuals survive. In this way the proportion of resistant individuals in the population increases. Repeated selection of resistant individuals will make that every succeeding generation of the pest will have a higher proportion of resistant individuals than the original population. Eventually, after repeated and more intensive use of the same pesticide to the same pest population, the pesticide becomes ineffective. Unfortunately, even under ideal IPM conditions pests can become resistant to pesticides. However, IPM can help in delaying the development of resistance.
 * //Development of resistance//**


 * 1.3 ** ** – the importance of agricultural labels as they relate safe practice and correct usage **

Restraints are usually the first item in the Directions for Use section of the product label. Restraints are limitations which apply to all approved uses of the product. Restraint statements are usually, but not exclusively, written as **DO NOT...** statements and each appears on a separate line. All restraints which appear on the product label must be observed. Some examples include: //DO NOT apply by Aircraft.// This restraint would make it illegal to apply the product by air. In the absence of such a restraint, aerial application of the product would be permitted (although aerial application may in some situations be specifically restricted under the //Agricultural and Veterinary Chemicals (Control of Use) Act 1995//. **__Directions for Use Table__** The crop on which the chemical may be used can be expressed in very specific or in general terms. The pest controlled is usually listed. The description of the pest can be specific or general depending on the circumstance.
 * __Restraints Statements__**

The rate of application of the chemical can be expressed in a number of ways including: as quantity of product per unit area, for example:- g, kg or L/ha; as product dilution, for example:- g, kg or L/100L; or per volume treated, for example:- g, kg or L/m³
 * __Rate of Application__**

The withholding period
 * __Withholding Period__**

Integrated Pest Management is when two or more of the following pest controls are used in combination to control a pest. IPM is beneficial due to one simple rule:
 * 1.4 ** ** – the use and potential for integrated pest management (IPM) **

//“The Total benefit is greater than the sum of the parts”//

If one method is used it will have a certain level of effect on both the pest and environment. Again if another is used it will have its own specific effect. However if both are used together, they not only have an averaged affect of both but a multiplied affect. By using different methods, a combination of cheap/expensive, fast/slow, long term/short term and good/ bad for the environment, the pest not only has to deal with one threat that they can grow accustomed to, such as resistance to chemicals, but have a lot more threats thus multiplying the effect.

The different methods are: diseases can be selected b) Through Genetic modification resilient species and breeds can be introduced e.g. BT cotton contains genes from the bacterium Bacillius thuringiensis that kills the Heliothis caterpillar and reduces chemical spray applications from between 12-16 down to just 6 c) By capturing certain male insects through pheromone traps they can be irradiated with radiation to make them sterile and then released to breed (talked about in Biological)
 * 1) **__Genetic:__** a) Certain breeds and species that are resistant to certain pests and

pheromones on it attracts certain insects to it which stick to it and can’t escape. Insects can smell the smallest trace of a certain pheromone from up to a kilometer away b) Simply picking up rotten fruit off the ground and burning it takes away the feedstock and attraction for many insects c) Ploughing in the stubble of a crop despite the desire to leave it to reduce erosion eliminates any pests or disease that are hibernating of the stalks waiting for the next crop.
 * 1) **__Cultural:__** a) Pheromone traps – a sticky card or box is lad out that has a dash of

with the females. The key to the success of this is that some species such as the screw fly only mate once, after which they die. With most other species, the female will only mate with one male as they assume they are then pregnant, they do not waste excess energy to mate with other flies. b) Releasing natural predators of a pest can reduce their numbers as long as the new animal does not grow out of control such as the cane toad.
 * 1) **__Biological:__** a) Sterile male fly species such as the screw fly are released to mate

quick and effective measure but it is expensive and resistance can build up b) Spraying cotton with powdered milk attracts protein eating insects that in turn eat the Heliothis caterpillar
 * 1) **__Chemical:__** a) Sprays, granules/pellets, dust and even wax blocks are used. It is a
 * 1) **Visit the National Water Quality Management Strategy and then describe what it is.** The National Water Quality Management Strategy is a document designed by Federal and State governments to guide authorities in the management of water quality, when considering new developments.
 * 2) **How does its objective make it different from pure conservation strategies? Is this important to farmers?** The NWQMS differs from traditional pure conservation strategies in that it is a tool for development. It is intended to help development, not prevent it. This is very important to producers wishing to establish new or different agricultural enterprises, e.g. irrigators, feedlots, intensive production on a large scale of both plant and animal enterprises.
 * 3) **List the impurities found in the groundwater that can be contributed to agricultural activity.**Impurities found in groundwater which can be attributed to agricultural activity include:
 * nitrates (from nitrogen fertiliser)
 * herbicides (atrazine)
 * 1) **What are the problems associated with such leaching of substances?** Nitrates leaching from the soil can lead to an increase in toxic blue-green algal blooms and destruction of downstream aquatic environments. Nitrogen fertiliser is expensive, and fertiliser leached is no longer available to plants, causing an increase in costs. Herbicide leaching can also cause an imbalance in downstream aquatic environments, in particular the destruction of aquatic and bank vegetation. Herbicides might break down, releasing potential toxic chemicals into the local ecosystem.
 * 2) **What are the problems associated with such leaching of substances?** During times of large water movements through the soil profile, e.g. floods, more leaching occurs of soluble soil nutrients, than during drier times, and during droughts, when little water movement occurs through the profile and nutrients may not be dissolved.
 * 3) **How did this project come into existence? How similar is this to the way in which Landcare Projects come into existence in rural Australia?** The Big Spring Basin Demonstration Project came into existence in the early 1980s when individuals who were getting wells sunk had water tested and found higher than expected levels of nitrogen and herbicides . Collectively they sought and got assistance from their local Soil and Water Conservation Authority. The project then grew following funding from the government. This is similar to the way many Landcare projects come into existence in rural Australia. A land degradation problem is encountered by an individual or group of neighbours, a collective network forms, and assistance and funding are obtained from a government program, usually on a shared cost basis.
 * 4) **When is a project such as this considered to be over? How can success be measured, if the process is ongoing?** A water quality monitoring and management project is on-going, and can have its success measured by the improvement in water quality by both structural works and changing current practices to a more sustainable approach. Good indicators used to show that success is likely will include the funding of the project and strong local support for the implementation of best management practices in water protection.
 * 5) **Why have soil nitrogen levels not increased significantly between 1970 and 1995, despite a doubling ff the nitrogenous fertilisers applied?** Soil nitrogen levels have not increased despite applications of fertiliser because leaching has caused almost all additional nitrogen applied to be 'lost' into the groundwater as soluble nitrates.
 * 6) **Read the final section on Funding. Should other parties be involved in the funding of land management projects on private farming properties? Why? Who benefits?** Whilst some people argue that public money should not be spent on private land because an individual owner gains the most, it is more realistic to adopt the concept that issues of water quality affect everyone eventually and so should be a priority for government spending. Directly or indirectly, everyone is affected by declining levels of water quality, as it affects food and fibre production so directly.

Aboriginal people have successfully managed their land for at least 40,000 years. This land provides the primary resources for clothes, food, building materials and all the other items needed for a healthy sustainable life. Traditional Aboriginal land use practices in Australia use resources in such a way that they are renewed and not exhausted. Aboriginal land use practices rely on an excellent knowledge of the area including the complex diversity of plants and animals found there as well as the physical environment and ecology in which they live. There is a deep understanding of season changes which effect all land use activities including food collection, mobility and ceremonial practices. Aboriginal people have a deep and spiritual attachment to the land that is difficult for non-Aboriginal people to appreciate. The types of traditional bush foods eaten, the way they are obtained and how they are prepared, varies both with locality and with the changing seasons. It is often thought that only the men hunt animals and that the women gather plant foods. This is not strictly true, as women also capture snakes, fish, goannas and tortoises and men may collect fruit, plant tubers and shellfish. Animal foods include kangaroos, possums, ducks, snakes, goannas, lobsters, shellfish, witchetty grubs, crabs, tortoises and seals. By eating a large variety of foods in a systematic and sustainable manner Aboriginal food gathering techniques can ensure that no one food source can be over-exploited. Plant foods eaten include wild fruit, nuts, berries, edible leaves and plant roots. Enough seeds are left so that there will always be new growth. The young of any animal species, or any female if it is still caring for its offspring are rarely killed. When collecting eggs from a bird's nest some are always left to hatch thus ensuring the survival of the species. Certain food taboos associated with specific clan totems also prohibited food being eaten by certain individuals. This complex system of food taboos adds to the overall sustainability of food sources. Agriculture and farming, from an Aboriginal world view, includes hunting and all forms of food collecting. Also included is intensive farming such as eel trapping, fish traps and yam growing. Indigenous peoples of the Torres Strait Islands have cultivated a number of plants such as bananas, taros, coconuts and yams. Existing vegetation was cleared and burnt and, after the crop was harvested, the soil was left fallow to restore its fertility. Techniques used by Aboriginal people to capture the animals include using nets to catch fish and birds, placing sticky sap on branches so birds could not fly away, using seeds to attract birds, using snares, swimming underwater and grabbing swimming water birds by the legs. Traditionally fish were caught by shell hook and bark-string line or speared, poisonous plants were soaked in waterholes to kill fish so they could be collected. In some places such as the Darling River at Brewarrina permanent stone walls were built in the river to form fish traps. Aboriginal peoples have had a lasting impact on the environment through their use of fire. Fire has been used for cleaning up the vegetation, making it easier to walk through the land and safer as snakes could be avoided. Fire was commonly used to promote the growth of valued plants. This regrowth of grasses attracts grazing animals, such as kangaroos, back to the area for easier hunting. Fire has also been used to drive out animals which can then be then killed for food. Traditionally smoke from fires was used to flush possums from their hiding places in hollow trees. In some instances a form of animal husbandry was used with Aboriginal men cutting holes in trees to provide homes for possums which could be raided at a later time. This controlled use of fire has been used for tens of thousands of years. This burning pattern has changed the appearance of the Australian bush with large areas of forest being replaced by open grasslands. Plant species which did not regrow well after fire declined in numbers, whilst more fire resistant species, such as grass trees, eucalypts and acacias, dominated. Very little plant propagation took place, though some groups did collect and scatter the seed of useful plant whilst others replanted edible yams. The women of the Torres Strait Islands cultivated a number of plants such as bananas, taros, coconuts and yams. They cleared and burnt existing vegetation and after the crop was harvested, the soil was left fallow to restore its fertility. **__ Sustainable Agricultural Production __**
 * Factors Contributing to the Degradation of Soil and Water **
 * Introduction**
 * Foods**
 * Looking after country**
 * Agriculture, farming and technology**
 * Growing up the country**
 * Plant propagation**


 * 1.2 ** ** - the historical development of Australian land use practices, including Aboriginal practices, up to the present day **


 * **Aboriginal** ||  **European**  ||
 * They were nomadic hunters and gatherers

Before 1788 there were about 400-500,000

After 1901 there were about 40,000

They had a high level of respect for the land including the soil and trees

They never hunted or killed more animals than they needed

They never killed the last few of any animal or plant in an area

They only killed the weak and never killed the leaders/strangest or pregnant (form of selective breeding)

No Soil Cultivation

Used native species

‘Slash and Burn’ than return years later = recovery time, no disease, form of rotational grazing || Stay in one place indefinitely

1901 – 4,000,000 Australian citizens (non-aboriginal)

20,000,000 people today

Produce food for a large number of humans world wide

Improved pastures and fertilizer = acidity problems

Monoculture = disease/pest plagues

Cultivate soil = damages soil structure

Removal of trees = salinity problems

Introduced foreign weeds, pests, disease eg. Rabbits, cane toads, foxes eg. Blackberry, Patterson’s Curse eg. Tetanus, pulpy kidney ||


 * __Inorganic fertilisers__**

The main components of inorganic fertilisers are phosphorous, potassium and nitrogen. Inorganic fertilisers are good because they are:
 * 1) Cheap to manufacture and buy
 * 2) High yielding
 * 3) effective


 * __Alternative strategies__**


 * 1) __Stubble retention:__ By leaving the stubble of a crop the soil is stable and does not lose nutrients to erosion.
 * 2) __Manure:__ Manure contain many nutrients and for many farmers is readily available
 * 3) __Crop rotation:__ by rotating crops, certain nutrients are not overused and by resting a soil once in a while or planting a legume crop can increase nutrient levels
 * 4) __Minimal Tillage:__ Nutrients are not lost through erosion

These strategies can be:
 * 1) expensive
 * 2) lower yielding
 * 3) not as effective

In the long term, organic methods are better for soil structure, yet not as high yielding in the short term. Inorganic fertilizers are high yielding in the short term but can make the chemistry of the soil instable by upsetting the pH balance, and effectively damaging soil structure.

Soil degradation is not just because of the use of fertilisers, cultivation techniques and other practices but the ‘overuse’ of them and also the use of them at inappropriate times such as when the sol is too wet or dry Salinity is, simply, the presence of salt in the root zone of plants. It is an enormous problem in Australia causing great loss of production. The cost to Australia each year is in excess of $270 million. Due to the extent of this problem, the Government is active in identifying and studying salt affected areas of [|Australia]. When discussing salinity the following terms are often used: If //Recharge > Discharge// the level of the watertable will rise. There are two types of salination caused by farming practices in Australia: dryland salinity and irrigation salinity. This is salinity in non-irrigated rural areas. It affects 2.5 million ha of Australian farmland. Clearing of native vegetation. Since the first white settlement of Australia enormous numbers of high water using native trees, shrubs and grasses have been replaced with shallow rooted crops and pastures. These introduced plants take less water from the ground water (i.e. reduce discharge). As less water is taken from the system, the level of the watertable rises bringing with it dissolved salts. Clearing means there is less discharge. A rising water table brings salts in to the root zone. The result is dryland salinity.
 * Salinity**
 * //Recharge// Where water is added to the ground water.
 * //Discharge// Where water is lost from the ground water.
 * Dryland salinity**
 * Cause**
 * Effects**
 * Reduced plant productivity because the plants have difficulty extracting water from the soil.
 * Dissolved sodium, chloride and borates can be toxic to plants and may raise soil pH.
 * Soil structure may be damaged leading to soil instability and erosion.
 * Death of native vegetation.
 * Water becomes unsuitable for livestock, humans and irrigation.
 * Solutions**
 * Plant salt tolerant pasture species e.g. marsh grass, tall wheat grass & saltbush.
 * Tree planting.
 * Change from shallow rooted annual pastures to deep-rooted perennial pastures such as lucerne and phalaris.
 * Avoid overgrazing.
 * Contour banks and drainage to control water flow.

This type of salination occurs in areas subject to irrigation, not just natural rainfall (i.e. greatly increased recharge.). It is estimated that 70 - 80% of irrigated land in NSW is under threat from a rising watertable. When the volume of added water is greater then the evaporation and transpiration occurring, the excess water goes into the groundwater , causing the watertable to rise. This problem is compounded by the high rate of clearing that precedes irrigation. Clearing and irrigation results in a rising watertable. This is called irrigation salinity. These are the same as in dryland salinity, however, the irrigation water usually becomes saline too, so the effects are quickly magnified. Fertilisers may be classified into one of two groups: Most fertilisers indicate on the packaging the percentage of the three major nutrients they contain i.e. nitrogen, phosphorus and potassium
 * Irrigation salinity**
 * Cause**
 * Effects**
 * Fertilisers**
 * **//Organic fertilisers//** These fertilisers include animal manures and animal or plant by-products. Animal manures contain small quantities of nitrogen, phosphorus and potassium, which vary with the kind of animal and its diet. Organic by-products include blood and bone, bone dust, cotton seed meal etc. Organic by-products generally have a higher nitrogen content than animal manures. Green manuring is also an organic method of improving soil fertility and the levels of organic matter.
 * **//Inorganic fertilisers//**These fertilisers are derived from inorganic sources and require more processing in their manufacture. They can be manufactured with varying mineral contents to suit particular situations. Some may provide mainly one element, these are called straights or they may contain a range of elements, called compounds or mixtures. They may come in various forms such as a powder, granule, liquid or gas. Some of the most widely used artificial or inorganic fertilisers include:
 * Superphosphate. This is the most common phosphorus fertiliser. It also contains calcium and sulphur.
 * Sulphate of ammonia, ammonium nitrate (nitram) and urea. These provide nitrogen.
 * Potassium chloride (Muriate of Potash) and Potassium sulfate. These provide potassium. These three fertilisers are known as **straights.**
 * Starter, Grower and Banana Special are examples of artificial or inorganic fertilisers that are known as **compounds and mixtures**.
 * //Elemental analysis//**

**Native grasses** By convention a graph presenting climatic data should be drawn with the rainfall as a histogram and the temperature (both maximum and minimum) as a line graph. This data can be put on the same graph with each y axis (left and right) having different units and labelled according to whether it is the axis for temperature or rainfall. Pasture growth is determined by the same factors that determine any plant growth. These include: climate; soil type; topography; and pest and disease susceptability. These factors determine the particular species that can be grown in the particular environment. This is known as the interaction with genotype and environment. In Australia, pastures have been the basis of our sheep and cattle production, providing feed throughout the year. Due to climate and geographical area, livestock production (grazing animals) has been extensive in nature. This is in contrast to many parts of Europe and North America where animals are kept in more intensive conditions, particularly during the winter months when the weather is cold and harsh. Recently has been an increase in the numbers of cattle kept in feedlots but Australia still remains predominantly extensive in its sheep and cattle production. Extensive animal production in Australia means that pasture production is extremely important. Pastures that provide year round feed, recover well from grazing, reduce the risk of soil erosion and are balanced in the species present are vital for successful sheep and cattle production. This piece of work provides a model that examines the environmental factors that effect the pasture growth on the Northern Tablelands. Skills such as: collecting climatic data from the Bureau of Meteorology web site and then drawing a graph; comparing rainfall and temperature data with estimated growth rates of several pasture species; and drawing some conclusions about the influence of the climate on the pasture growth; are used extensively. There are three other activities that you may select from once you have completed this one. Each one uses the skills you will have developed by completing this activity and the climatic information and pasture growth data for a particular climatic region: Another form of sustainable farming practice is diversification by have money elsewhere. This vertical and horizontal integration is like a back up plan in time of hardship.
 * Sustainable Resource Management **
 * Plant Production Systems **
 * Advantages of disadvantages of using native grass species in a pasture system.**
 * **Advantages of using native grass species in a pasture system** ||  **Disadvantages of using native grass species in a pature syste**  ||
 * Many native grass species are drought-resistant. || Native grasses tend to be less nutritious than many introduced species (depending on the stage of growth). ||
 * Native grasses tend to require low levels of inputs e.g. fertiliser, water. || Native grasses can be less palatable tp stock than many introduced species ||
 * Many native grasses are well adapted to surviving heat and low rainfall. || If incorrectly managed, less desirable native grass species will overtake more desirable native grass species ||
 * Native grasses are very useful in marginal areas, that is areas of low rainfall. || There are problems in collecting, cleaning and sowing the seeds of native grasses. ||
 * Factors affecting pasture growth and production**
 * Grazing systems**


 * Constraints on Plant Production **
 * A)** **Describe two mechanisms of interference in plant communities.**

Interference is used to describe the interaction, which takes place between plants when occupying the same environment, whether it be concurrently or over a period of time. Competition if the most commonly used term to describe interference. Competition occurs between plants for resources in the environment such as mineral nutrients, water, space, sunlight and carbon dioxide, during interference.

Water is one mechanism of interference, which may affect plant communities. Relative root distribution of a plant has great influence over competition for water. The higher the density of a plant population, the smaller the individual plants will be, therefore making their roots more shallow since space is limited. These small individual plants will then suffer more from moisture stress than those that have deeper root systems. There are also plant species which can exploit soil moisture under stress, to further develop their root zone and to survive. Natural species use less moisture at depth and are able to survive very dry periods by slowly growing down to a low moisture level. However these species are only 1/10 as productive as the improved species which can rapidly remove all the available water in the soil within a 122cm depth. Water is an important resource for plant competition, as it is responsible for turgor, mineral transport, cooling and photosynthesis.

Light is another mechanism of interference in plant communities, as it is a major input for photosynthesis. Competition occurs what one plant shades or intercepts light from another. The plants source of energy is then lost. An example of this, is when lower plant leaves in a canopy die or wilt, as a result of the upper leaves shading light from them. The superior plant does not have to have the most foliage, but has to have the most advantageous position compared to its competitors. For example, grasses and clovers have different leaf shapes and sizes, with leaf blades of grasses being long, narrow and vertically inclined and clover leaves being round and horizontally inclined. The ability of plant leaves to capture the light effectively is influecned by Leaf Area Index (LAI), which is the ratio of area of leaves to the area of ground covered by the leaves. The position of the leaves on the plant, the distribution of the leaves in the canopy and the angle of the leaves all contribute to the effectiveness of the plant when intercepting light. C4 plants are also more able to use higher density light intensities than C3 plants. The duration of light in a day also affects the rate of photosynthesis and flowering.


 * B)** **Evaluate how farmers use plant interference to their benefit. Illustrate your answer, give 3 examples.**

Interference involves competition, which is necessary at certain levels to achieve maximum yield per hectare. The yield per hectare increases as the density of the crop increases, creating competition between plants. Yet the level of density can only reach a particular level, because when it exceeds this level, the yield decreases. At a high density plants exploit the environment and its nutrients and are able to reach maximum yield at a rapid rate. At a medium density it takes longer for the plants to spread, develop and reach maximum yield. Yet at a low density plants are unable to fully use up all nutrients in the surrounding environment no matter how long they are given. Competition can only benefit the yield crop if the soil is uniform, fertility is satisfactory, weed control is sound and if the seedlings are evenly spaced. If all these things are performed, not only is the plant growth at its maximum, it also shortens the period of which the crop may be susceptible to pest or weed damage. The crop also appears to be more uniform in appearance, height, head size and maturity. An example of this is when legumes are sown with grasses in a pasture, which provides more protein amd makes the soil more fertile. Rape may also be sown with oats because, since it germinates and grows faster, it will provide shelter for the young oat plants. Clover may also be sown with oats, to produce nitrogen and supply it to the oat crop. When the oat crop is harvested, the clovers may also then be grazed. Interference can be detrimental to plant growth and development when the plant or crop is deprived of lifes essentials, such as light, nutrients, water and carbon dioxide. But interference in the form of natural competition may increase crop yield and benefit the final product for the consumer. Interference therefore needs to be taken into consideration to achieve maximum results.

**Manipulating the nitrogen cycle to maximise production** **Answers**
 * Managing Plant Production **
 * **Technique** ||  **Outline**  ||  **Advantages**  ||  **Disadvantages**  ||  **Judgement**  ||
 * Green manuring || Growing a legume crop and ploughing it back into the ground. || The growing legume increases N through the symbiotic relationship with rhizobia bacteria fixing atmospheric N into a useable for plants. N rich OM increases when the crop is ploughed into the soil. || Farmer forgoes the financial return of the crop not harvested but ploughed in instead. N is not immediately available from the OM incorporated as it must first undergo decomposition. || This technique is highly beneficial as it has the double action of increasing N through legume growing and incorporation of N rich OM that releases N in a less leachable form than chemical fertilisers. Short term costs are more than offset by reduced expenditure on fertilisers and long term soil sustainability. ||
 * Crop rotation || Growing a different crop in the same paddock over successive years, e.g. wheat, chick peas, canola. || By incorporating a legume into the rotation, particularly if the legume crop is for green manuring, the advantages are as above. Each crop uses different quantities of different nutrients, therefore not exhausting the same soil nutrients year after year. || If a legume crop is incorporated and green manured and not harvested, the disadvantages are as above. Different machinery may be required for sowing and harvesting of each crop. Farm manager must have knowledge and expertise with the production of a variety of crops. || This technique is highly beneficial, particularly when a legume is incorporated into the rotation. It has the double action of increasing N through legume growing and incorporation of N rich OM that releases N in a less leachable form than chemical fertilisers. In addition there is a reduced drain on the same nutrient balance each year and a break in the pest and disease cycle as different crops are grown. This reduces the need for chemical usage with long term sustainable outcomes. ||
 * Adding N fertilizer || Addition of nitrogenous fertilisers, e.g. urea, nitram at the time of sowing or during the growth cycle. || N is added in the form that is able to be used by the plant immediately. A measured amount suitable to the crop needs and soil nutrient deficiency can be supplied. || Synthetic N fertilisers are expensive to buy. Toxicity and pH problems can arise from long term use indiscriminate use of synthetic fertilisers. || A viable option if used appropriately, after analysing soil nutrient status and soil pH and in line with crop demands. If a particular crop has high nutrient demands this method is useful in avoiding depletions. ||
 * Legume inoculation || When high numbers of the appropriate rhizobia bacteria are not present in the soil they must be added to the seed at sowing time in a process called inoculation. Inoculated seed may be pelleted by adding a protective layer of fine lime to improve the survival of the rhizobia, particularly when sowing into acidic soils or if inoculated seed is in direct contact with acidic fertilisers such as superphosphate. || Increases the chance of legume crop growing and producing to its potential. Lime pelleting helps to reduce increase acidity problems. || Additional cost and time involved. || If there is any doubt about the presence of appropriate rhizobia bacteria in the area to be sown then the small increase in cost and labour input is well justified. The alternative risks the chance of legume crop failure or severely decreased production. ||
 * Liming/pH || Applications of lime help reduce the problem of soil acidification. Soil acidification can lead to reduced production as some plant species become intolerant to the rising acidity and soil nutrients may become unavailable for plant growth. || Helps reduce the increase in acidity so a broad range of plant species can be grown successfully and soil nutrients are available for plant growth. || Extra cost for lime and its application. || If soil acidification is a problem then it is advisable to apply agricultural lime. This will have both short and long term sustainability advantages. In the short term crop production will be improved and in the long term sustainability of the environment will be enhanced. ||
 * Planting deep-rooted plant species || Deep rooted plant species help to open up the soil, aerating and allowing water infiltration. This encourages populations and activities of microbes and invertebrates, resulting in a healthier soil that breaks down OM releasing ammonium and nitrates for plant growth. || Increased breakdown of OM and hence release of available N into the soil. Increased aeration and water infiltration for microbes/invertebrates and plants. Increased water infiltration reduces waterlogging and hence denitrification. || High costs involved in planting trees and other deep rooted species plus costs involved in establishment, e.g. fencing, weed control. || An essential management practice for the long term sustainability of the environment. Not only is the soil a healthier environment but vertebrate biodiversity is increased with shelter belts created for both native and farm animals. ||
 * Please note:** You may have included some other techniques, e.g. pasture mixes, improved structure in your answers. The techniques included in this table are not exhaustive and are only provided to give you some good examples

**Plant Hormones** The annual production of potatoes in Australia is approximately 1.3 million tonnes with a farm gate value of $480 million. There are three different end uses or markets for potatoes: fresh, french fries and crisps. Each of these end uses or markets requires varieties with different characteristics. Potato breeders try to produce new varieties that:
 * **Hormone** ||  **Where produced**  ||  **Effects in plants**  ||  **Roles in commercial plant production**  ||
 * Auxins || Leaf buds, young leaves and developing seeds. || Cell elongation, secondary thickening of roots and stems. || * Production of seedless fruit: cucumbers and tomatoes.
 * Promote fruit set.
 * Prevent fruit fall, e.g. apples.
 * Weed killers (herbicides) applied at high concentration promote uncoordinated growth and finally death, particularly in broad-leaved weeds.
 * To promote root growth in stem cuttings synthetic auxins such as naphthalene acetic acid (NAA) and indole butyric acid (IBA)are used.
 * Induction of flowering in pineapple (actually caused by the auxin-induced production of ethylene). NAA is generally employed as the auxin. ||
 * Gibberellins || Seeds and young stems. || Stem elongation, induces seed germination || * Enhanced production of seedless grapes. Bigger, more uniform bunches with larger fruit are produced. Among other effects, the gibberellin causes lengthening of the peduncle (stalk) attaching each grape to the cluster, thus permitting larger grapes to form. Virtually all the grapes that go to market are now treated with gibberellin.
 * Treatment of oranges to prevent rind senescence, to permit longer storage on the tree,thus extending the marketing period.
 * Enhancement of flower bud formation and improvement of fruit quality in cherries.
 * Improvement of fruit setting in apples and pears, particularly under weather conditions that are not ideal for setting fruit.
 * To substitute for a chilling requirement in instances such as:
 * 1) flower induction for seed production (radish).
 * 2) increased elongation (celery, rhubarb).
 * 3) earlier flower production (artichokes).
 * The production of hybrid cucumber seed. Most high-producing cucumbers are F1 hybrids. GA sprays induce the production of male flowers on cucumber plants that normally produce only female flowers. The seed from neighbouring all-female plants of a different strain is then exclusively hybrid.
 * Increased malt production. The addition of GA to germinating barley during beer production enhances a-amylase production so that more malt is produced more quickly. As the malt is the raw material for fermentation, a greater production of beer is made possible by this technique.
 * Increased sugarcane yield: GA promotes the elongation of sugarcane stalks with no change in the sugar concentration, so that the net yield of sugar is increased. ||
 * Ethylene || Ageing leaves, ripening fruit. || Promote fruit ripening. || * Ethylene gas is used commercially for ripening fruit, particularly bananas. There are also synthetic compounds, such as ethephon (chloro-ethanephosphonic acid) that can be sprayed onto plants in solution; once inside the tissues ethephon breaks down to liberate ethylene. Ethephon is used to promote ripening on the tree, leaf abscission in ornamentals, growth control in seedlings and flowering in pineapples.
 * Enhancement of uniform fruit ripening and colouration. This has been shown to be of particular value in field tomatoes picked at a single time by machine.
 * Acceleration of fruit abscission for mechanical harvesting. This provides a potential area of use in a wide variety of fruits such as grapes, cherries, and citrus.
 * Promotion of female flower production in cucurbits (cucumber, squash, melon) so as to increase the number of fruits produced per plant.
 * Promotion of flower initiation and controlled ripening in pineapples. ||
 * **Cytokinins** || In growing roots, developing seeds. || Promotes cell division, growth of lateral buds and leaf expansion. || * The treatment of holly for festive decorations enables its harvest many weeks prior to use.
 * Post­harvest sprays or dips are now available to prolong the storage life of green vegetables such as asparagus, broccoli, and celery.
 * Used to promote shoot production in tissue culture. ||
 * **Abscisic Acid** || Roots and mature leaves || Stimulates stomatal closure, locks shoot growth and stimulates dormancy. || No practical uses. ||
 * Introduction**
 * 1) **What is IPM?**Integrated Pest Management (IPM) is the term used for a wide range of strategies to prevent pests of all kinds from reaching economically damaging levels in crops. A pest can be an insect, mite, vertebrate (such as birds), disease or weed.By using a range of tactics to deal with pests, it removes and/or minimises the reliance on any single method of control, e.g. chemical sprays. IPM strategies fall into the following categories: biological, cultural (or managerial), chemical, physical (or mechanical) or genetic.
 * 2) **Identify three benefits of using IPM.**The benefits of using IPM are many and varied, but may include:
 * Reducing health risks to growers, their families, staff and consumers.
 * Reduces negative impacts on the environment.
 * Encourages natural enemies to help manage pests.
 * More cost effective use of treatments.
 * Encourages more regular inspection of crops, thus improving likelihood of detecting other potential problems earlier, resulting in swifter remedial action.
 * 1) **Explain what damage the leaf miner does to the tomato plant and why you think control measures are important.**The females puncture leaves and lay eggs. These punctures can serve as entry points for disease-causing bacteria and fungi.Maggots cause damage by feeding between the upper and lower surface of the leaf, making tunnels or mines as they move along. Heavy attack leads to large-scale necrosis of leaf tissue, eventual shrivelling of the whole leaf that may result in complete defoliation of crops. Defoliation of tomato plants may also expose fruits to sunburn and thus affect their market value. Heavy infestation reduces the photosynthetic capacity of the plant and affects the development of flowers and fruits. However, mature plants of most crops, such as tomatoes, can withstand considerable leaf mining, especially on the lower or outer leaves. In other crops, where feeding occurs on the marketable part of the crop, even slight damage may lead to rejection of the crop. This is particularly important for export crops, as most Leaf miner species are considered quarantine pests in the EU and there have been rejections of produce exported to Europe.
 * Evaluate the likely environmentally sustainable implications of adopting IPM strategies to control leaf miner damage in tomato crops.**Integrated pest management (IPM) is an approach to controlling pests which emphasises minimising crop loss by all means at the growers disposal including the use of resistant and tolerant varieties, cultural methods, biological controls, insect growth regulators and pheromones, other genetic methods (such as the use of sterile insects and transgenic plants) and the careful application of chemicals. The ultimate goal of IPM is to ensure production of abundant, high quality food using environmentally and economically sound methods. Sound IPM programs should coordinate pest management activities with production methods in order to achieve economical and long-lasting solutions to pest problems. The components that are essential to any IPM program include accurate identification of pests, field monitoring, control action guidelines and effective methods of prevention and control, including the use of appropriate pesticides when needed.
 * meet market requirements
 * are adapted to the environments where potatoes are grown in Australia
 * are resistant to diseases.

It is important to understand how reproduction in potatoes occurs. When grown as a crop they are grown vegetatively from tubers (asexual reproduction). Potatoes also produce flowers and fruits that contain seeds (sexual reproduction). Plant breeders are very interested in this form of reproduction because it is the mechanism that allows them to combine the desirable characteristics of one variety with the desirable characteristics of a second variety and produce a new variety that combines these desirable characteristics. Consider this hypothetical example. A new variety of crisp potato is needed that is resistant to Powdery Scab disease. An existing variety //Not as thick as some,// makes crisps that are light coloured, have great taste and texture and has a high yield, but is susceptible to Powdery Scab. Another variety, //Smiths Wonder//, makes crisps that are dark coloured and do not taste very good. This variety is high yielding and is not susceptible to Powdery Scab. The plant breeder crosses these two varieties by taking pollen from //Not as thick as some// and transfers it to the flowers of //Smiths Wonder//. When the //Smiths Wonder// plant matures the seeds are collected from the fruits. Each seed is a unique combination of genes from the two parents. These seeds are then planted and the characteristics of the tubers, produced by each resulting plant, are assessed. Each plant is a new variety having a unique genetic make up. The individual plants (new varieties) that have a combination of good yield, quality crisps and resistance to Powdery Scab are selected and further generations of them are grown using their tubers. Further testing of each new variety is done and one or two new varieties are released for commercial production.
 * Market requirements**
 * **Market** ||  **Requirements**  ||
 * **Fresh** || Yield, Tuber size (120 – 300 g preferred), bright skinned with no blemishes, do not disintegrate when cooking, have acceptable taste and texture, not susceptible to pests and disease. ||
 * **French Fries** || Yield, Tubers 280 – 450 g, long and regularly shaped, specific gravity above 1.080g/cm3, light coloured when fried, do not disintegrate when cooking, have acceptable taste and texture, not susceptible to pests and disease. ||
 * **Crisps** || Yield, Tubers 45 – 90 mm diameter, round or slightly flattened, specific gravity 1.085 to 1.095 g/cm3, crisp colour must be uniform and light, do not disintegrate when cooking, have acceptable taste and texture, not susceptible to pests and disease. ||
 * Breeding new varieties**

Extract from //Stage 6 Agriculture Syllabus// NSW Board of Studies Amended 2009 Animals in intensive livestock production systems require a diet which is balanced for the specific requirements of the animal. This means it needs to contain the correct proportions of: In addition to these components, water must also be available. An animal needs energy in its diet for several reasons: The energy in a diet can be provided by many different components, but the feeds which supply energy in the greatest quantities are grains and fats or oils. Ruminant animals cannot tolerate too much grain in a diet, as a condition called //grain poisoning// or //acidosis// can occur. The provision of high energy for ruminants must take this into account. Protein is the material which makes up muscle, skin, wool and most of the bodies of animals and needs to be provided in the diet of animals for them to make meat, milk and eggs. Protein is made of chains of chemicals called amino acids, and in monogastric animals such as chickens, several specific amino acids called essential amino acids must be present in the diet. The most critical of these are //Cystine// and //Methionine//. Ruminant animals such as cattle do not have the same requirement of essential amino acids in the diet as the fermentation process in the rumen provides these to the animal. High protein feeds are usually those which are called 'meals' and include by-products from the manufacture of other products. Examples of these are sunflower meal, meat meal, cottonseed meal. High protein feed are usually quite expensive and should not be provided to excess in a diet. High producing animals need more protein in their diet than lower producing animals.
 * Animal Nutrition **
 * Animal nutrition**
 * the fate of energy in animal nutrition
 * managing the nutritional requirements of monogastrics and ruminants in terms of their digestive physiology
 * Introduction**
 * Energy
 * Protein (and specific Amino Acids)
 * Fibre
 * Vitamins
 * Minerals.
 * Energy**
 * **Maintenance**: to provide energy for basic body functions such as digestion and blood circulation.
 * **Production**: to allow the production of meat, milk eggs etc.
 * **Growth**: to give energy for the growth of bone and muscle.
 * **Reproduction**: to provide energy for the growth of a calf, lamb or the production of eggs.
 * **Activity**: for muscle movement as the animal walks and moves.
 * Protein**

Fibre is needed in a diet to provide bulk as the food passes through the animal. A ruminant animal (cattle, sheep, goats and deer) is able to ferment fibre and provide energy, but a monogastric animal such as a chicken or pig cannot ferment fibre for energy. The diets required by monogastric animals need more grain and less fibre than those for ruminants. Minerals such as calcium and phosphorus must be present in the diet for the metabolic processes in the animal which require these. Vitamins are also necessary in the diet, ruminant animals have much lower dietary requirements for vitamins as many are synthesised in the rumen by the microbial fermentation process. Each type of animal has specific nutritional requirements which are based on the energy, protein, fibre, minerals and vitamin needs of that animal and also take into account the way the species digestive system uses the food
 * Fibre**
 * Vitamins and minerals**
 * Formulating diets**
 * Animal Growth and Development **
 * CORE – Animal production systems **


 * 1.1 ** ** – the similarities and differences in the anatomy and physiology of ruminants and monogastrics **

n **Reticulum/Rumen** – Called the paunch it continuously churns up food and acts like a sieve, sending large particles back to the mouth to be chewed (rumination). It also has lots of bacteria, protozoa and fungi which breakdown carbohydrates into fatty acids, and synthesis proteins and vitamin B n **Omasum** – sometimes called the bible because of leaf like partitions that line the walls. Removes 60-70% of water. n **Abomasum** – The “true stomach”. Gastric juices, containing enzymes break down starches, proteins and fats into soluble compounds which is absorbed into the blood stream. n **Small Intestine** – Pancreatic juices break down carbohydrates, fats and proteins into simple components including monosaccharides, amino acids, glycerol and fatty acids which are absorbed into the blood stream. || n **Mouth -** Saliva lubricates the dry feed to pass easily into the stomach. It also helps neutralize acids formed by stomach organisms. n **Stomach** – secretes gastric juices which consist of HCl and the enzyme pepsin (for protein digestion) n **Small Intestine** – Pancreatic juices break down carbohydrates, fats and proteins into simple components including monosaccharides, amino acids, glycerol and fatty acids which are absorbed into the blood stream. ||
 * ** Ruminant Digestion ** ||  ** Monogastric Digestion **  ||
 * n **Mouth -** Saliva lubricates the dry feed to pass easily into the stomach and maintains the fluid consistency of the rumen. It also helps neutralize acids formed by rumen organisms.


 * 1.2 ** ** – the nutritional requirements of a selected animal **

There are five essential components of an animal’s diet:
 * 1) Water
 * 2) Carbohydrates
 * 3) Protein
 * 4) Fats
 * 5) Vitamins and Nutrients


 * 1.3 ** ** – the fate of energy in animal nutrition **

Energy metabolized for the food eaten is used for: Only part of the total energy in food is available for use. Normally a certain proportion of food is non-digestible (some fibre) and is passed out in the faeces. Some energy is lost as urine or methane gas in ruminants. The energy that is available is called the **Metabolisable energy**. Some energy is lost as heat and when subtracted from the metabolisable energy the **net energy** is found. There are two types of energy requirements:
 * Muscular work (breathing, walking, etc)
 * Keeping the body warm
 * Storing energy for growth
 * 1) **Maintenance Energy:** needed to keep the animal alive and healthy, not allowing for growth and development
 * 2) **Production Energy:** needed for growth and development

The energy requirements of an animal depend on: n Its Body weight n The amount it is producing n Its environment (cold = more energy) n Degree of stress (high stress = more energy)
 * 1.4 ** ** – the processes of growth and development in animals in terms of the proportion of muscle, fat and bone **

When an animal is young the proportion of bone to both muscle and fat is high. It also grows the fastest when an animal is young as it is required to support the animal.

At about the age of puberty, muscle growth takes over as the fastest rate of growth. This is because this is where most of the energy from an animal’s nutrition goes into. Muscle is needed by the animal to move and function properly. As can be seen in the diagram (middle) the proportion of muscle to bone and fat is highest during the middle of its life. After this, as the animal becomes less active, muscle is not needed as much and excess energy goes into fat which takes over.

Fat continuously increases in an animal increasing faster in an animals older years as excess energy is all stored as fat. This is why most beef cattle are slaughtered before they are too old, so that they have maximum muscle which is the meat we eat and not too much fat.


 * 1.5 ** ** – breeding systems and their genetic basis to improve quality and production of animals **

Estimated breeding values (EBVs) for beef cattle, Australian breeding values (ABVs) for dairy cattle and LambPlan for sheep all work on the same principal. They are estimates of an individual animal’s genetic merit as a parent if mated to an average animal. The are calculated by a procedure called ‘Best Linear Unbiased Prediction’ which measures the performance of the animal such as growth, calving ease and carcass attributes, and comparing them with others in the same herd in the same conditions. Computers have allowed the parents and progeny’s results to be included to improve the accuracy of the estimates. This system has allowed farmers to evaluate and pick out superior animals to produce superior progeny.
 * __ EBVs/ABVs/LambPlan __**

By selecting complimentary animals, such as a skinny animal and a large animal or a short animal and a tall animal, farmers can breed them to hopefully produce offspring that are a compromise of both. A farmer can also breed the best animals to develop a line of superior animals. The introduction of systems such as EBVs has revolutionized the industry by allowing farmers to make more informed decisions.
 * __ Selective Breeding __**

By crossing various breeds a farmer can develop a breed that exhibits desirable qualities of both breeds but this is a long term program. This was done in the tropics of Qld to produce desirable breeds such as the Braford and Brangus which have the drought and tick tolerance of the Brahman and the production levels of the Angus and Heraford.
 * __ Crossbreeding __**

AI is a relatively new breeding system which is a similar form to the selective breeding. Semen from superior selected animals are extracted and frozen. They can be transported around the world which is an advantage over natural selective breeding. The sperm can also be graded and the best can be chosen.
 * __ Artificial Insemination __**


 * 1.7 ** ** – the factors that limit the fertility of farm animals **

There are genetic differences in fertility between species of animals as well as between breeds of the same species. Some animals are infertile because they inherit a genetic abnormality in the anatomy of the reproductive glands.
 * __Genetics__**

The rate of development of the reproductive organs and the onset of puberty are determined more by weight than age. Some animals are often given more feed prior to joining. This is called flushing and increases ovulation rate and fertility. Feeding pregnant animals increases foetal growth and may result in higher birth weight. A deficiency in vitamin A in males can decrease sperm fertility.
 * __Nutrition__**

Temperature and day length can influence reproduction. Temperature can reduce birth weight weaken the animal. High temperature also has a harmful effect on sperm. Colder temperatures can lead to heavy losses in new born lambs. Many animals mainly sheep base their breeding cycles on day length.
 * __Climate__**

Diseases that affect the health and vitality of a animal can reduce its reproductive capacity. Some may affect the organs themselves, stop production of sperm or ova, or stop implantation of embryo. Some common ones include oestrogenic infertility and leptospirosis which can cause abortion in cows.
 * __Disease__**

Some management techniques to increase fertility and fecundity are: n Accurately detect heat when inseminating n Selectively cull n Determine optimum mating time n Prevent and control disease n Provide adequate nutrition
 * __Management__**


 * 1.8 ** ** – ethics, welfare and legal issues and requirements **

Owners and managers are all responsible for the health and well-being of the animals in their control.

The basic requirements for the welfare of animals are:
 * __Welfare__**


 * 1) a level of nutrition adequate to sustain good health and vigour
 * 2) access to sufficient water of suitable quality to meet the animals’ needs
 * 3) Social contact with other animals, but with sufficient space to stand, lie down, stretch and perform normal behaviour
 * 4) protection from predators
 * 5) protection from injury and disease, and treatment if they occur
 * 6) protection from adverse extremes of weather where possible
 * 7) provision of reasonable precautions against the effects of natural disasters, eg fodder storage for a drought.
 * 8) handling facilities which with normal use do not cause injury and which minimizes stress to the animal

There are certain legal procedures that farmers and others in the industry must follow, including:
 * __Legal Issues__**


 * 1) Cruelty to animal laws
 * 2) Legal recourse of chemical drift onto other properties
 * 3) EPA – effluent disposal – dairies have to have on farm treatment systems and settling ponds to clean water before releasing it or reusing it in dairy. These settling ponds take up a lot of space that is valuable to a farmer. Effluent water goes through flocculation that coagulates the solids that are then separated and sold as fertilizer, etc
 * 4) Processing plants are required to release water into the environment at a certain temperature to stop thermal pollution.

The main ethical debates in the industry revolve around technologies including Artificial insemination and Embryo Transfer. That it is not natural to conduct these processes on animals sparks concern in animal enthusiasts. For this reason, animals are not subjected to it day in, day out but are only subjected occasionally.
 * __Ethics__**

The following factors may affect the fertility of farm animals: Genetics/heredity affects the fertility of farm animals in a variety of ways. Some animals may be genetically infertile. Genetic mutations can occur which can produce infertility. They can also give rise to abnormal development in embryos so much so that the young fail to develop properly and cause foetal death or atrophy. These are called lethal factors. Poultry seem to be more affected with lethal factors than other animals. A peculiar form of sterility occurs in heifers born twin to a bull. In about 90% of such cases, the foetal circulations fuse. The male then remains normal but the female becomes a **freemartin**. To some extent, the female becomes masculinised by androgen produced by its twin.
 * Animal Reproduction and Genetics **
 * Animal reproduction and genetics **
 * Heredity/Genetics
 * Nutrition
 * Age
 * Climate
 * Disease
 * Management
 * Heredity/Genetics**
 * sows can give birth to up to 20 piglets in one litter while cattle usually produce a single calf from each pregnancy || Genetic differences do exist:
 * between animal types e.g. pigs have lots of piglets in comparison with cattle which usually have a single calf
 * between breeds of the same animal type e.g. Border Leicester sheep commonly have lambing percentages of 150 while Merinos tend to have lambing percentages of close to 100
 * within breeds e.g. Booroola Merinos have a high incidence of twins in comparison to other strains of Merinos. ||

Generally the heavier the animal the more fertile, but overfat animals may have difficulty mating, conceiving, and birthing. Puberty is determined by body weight not by age of the animal. Poor nutrition may cause irregular cycles in females, reduced ovulation, weak offspring, pregnancy toxaemia or reduced twinning. In males poor nutrition may reduce sperm quantity and quality. The amount of food given to ewes immediately before they are joined is also of considerable importance. Experiments have shown that, if at that stage, a ewe is given a generous plane of nutrition she is likely to shed more ova than normal. This results in a higher lambing percentage by increasing the number of twin births. This procedure is known as **flushing.** There is evidence to suggest that the numbers of sperm produced by rams may be increased by feeding a high energy and high protein diet for about six weeks before the mating season. The amount of food given to the pregnant mother also influences birth weight of offspring and heavier offspring have a better chance of surviving. Conversely, the undersized new born animal has less chance of surviving and frequently dies in the first few days following birth. Such an animal is less able to maintain its body temperature and may die quickly if born in cold weather. If over-fed, the pregnant animal may suffer difficulties in birth which could also lead to death of either the offspring or mother or both. Whilst deficiencies in protein may cause infertility, it has also been shown that copper deficiencies in some eastern states of Australia causes infertility in cows while a deficiency in vitamin A prevents normal sperm production in bulls and rams in some areas.
 * Nutrition**
 * In order to avoid pregnancy toxaemia this ewe was steamed up in the latter stages of pregnancy. || Under nutrition in late pregnancy, particularly in ewes carrying twins, may cause pregnancy toxaemia. This has given rise to the practice of **steaming up.** **Steaming up** is feeding technique where females are put on a rising plane of nutrition in the latter stage of pregnancy. It increases birth weight and milk production. ||

The effect of age is closely linked with nutrition, as puberty is determined by body weight not by the age of the animal. The physical size of animals may affect their ability to mate, carry a foetus or give normal birth to offspring. After puberty, fertility generally increases for some time then decreases when the animal gets too old. In contrast, goats have a greater chance of twin kids as they age.
 * Age**

Some species are polyoestrous (pigs and cattle), this means that they cycle throughout the year. Other species are seasonally polyoestrous meaning that they breed only during particular months of the year (horses, sheep, poultry and goats). The decreasing daylight hours stimulate ewes and does to cycle while the increasing daylight hours stimulate hens and mares to cycle.
 * Climate**
 * Daylength**

Internal parasites can reduce the income of beef cattle farmers by:
 * Animal Pests and Diseases **
 * reducing the growth rates of young steers and heifers
 * reducing calving percentages
 * the cost of treatment, both in drenches and labour.


 * Animal Ethics and Welfare **
 * Battery cage egg production**
 * 1) **Describe the features of the egg production system** Hens are housed in wire cages, often known as battery cages. These cages vary in size, from 1800cm2to 11, 000cm2 with the number of birds (between four and 20) kept in each cage varying with the cage size. The Model Code of Practice for the Welfare of the Domestic Fowl requires laying birds to have a minimum of between 550cm2 and 1000cm2 depending on the weight of the bird. The cages are housed within a shed, which typically may have many hundred of birds in each shed. The birds are provided with pellets for food, ad lib and drinking water is usually supplied by nipple drinkers. The birds do not have perches or nesting materials. The eggs are laid onto wire cage floors and roll to the front of the cage for collection.
 * 2) **What is the percentage of eggs in Australia produced by this system?** Approximately 80% of eggs purchased in Australia are produced from the cage system.
 * 3) **Construct a table to present the advantages and disadvantages of this system.**
 * **Advantages** || **Disadvantages** ||
 * Protection from the weather and predators like eagles, snakes, foxes and feral cats. || Reduced social interaction with other birds. ||
 * Lower occurrences of manure-borne diseases and parasites. || Considerably less space to roam, but enough space to stand upright and stretch their wings. ||
 * Reduced need for veterinary medications and intervention. || Inability to display natural behaviours like nesting and dust-bathing. ||
 * If a bird does become sick it can easily be identified and removed for treatment. || Inability to perch which can result in lower bone strength and increased bone breakage during removal of hens at the end of lay. ||
 * Reduced risk of disease such as avian influenza. ||  ||
 * Better protection from in-fighting and cannibalism. ||  ||
 * Costs of production are lower, hence price of eggs is lower than other systems. ||  ||
 * Barn laid egg production**
 * 1) **Describe the features of the egg production system** Hens in this production system live in a shed, roaming around. The sheds contain perches, litter, nest boxes, feeders and drinkers. The size of the sheds varies from those housing 500 birds through to those housing 5,000 birds. This system allows hens to move around, stretch, flap their wings, socialise, perch, scratch the litter, dust bathe and lay their eggs in nest boxes.
 * 2) **What is the percentage of eggs in Australia produced by this system?** About 5% of eggs sold in Australia are barn laid.
 * 3) **Construct a table to present the advantages and disadvantages of this system?**
 * **Advantages** || **Disadvantages** ||
 * Protection from the weather and predators || Increased occurrence of manure-borne diseases and parasites compared to cage system ||
 * Ability to move around within the shed || More difficult to identify and remove birds for treatment if required ||
 * Ability for greater social interaction between hens || Increased risk of feather-peaking, fighting and cannibalism ||
 * Ability to express some natural behaviours, e.g. dust bathing, perching || Increased risk of broken bones due to birds flying into objects ||
 * || Costs of production are increased resulting in increased price of eggs ||
 * || Greater labour requirements for monitoring birds and managing system ||
 * Free range egg production**
 * 1) **Describe the features of the egg production system** Hens in this system have both sheds and also access to the outdoors for at least 8 hours each day. Perches, nest boxes, food and water are provided in the sheds. Some small free range systems have mobile shelters that can be moved around to allow rotation of the range area.
 * 2) **What is the percentage of eggs in Australia produced by this system?** About 15% of eggs sold in Australia are produced from free range systems.
 * 3) **Construct a table to present the advantages and disadvantages of this system?**
 * **Advantages** || **Disadvantages** ||
 * Access to the outdoors || Increased occurrence of manure-borne diseases and parasites compared to cage system ||
 * Ability to move around in the outdoors and indoors || More difficult to identify and remove birds for treatment if required ||
 * Ability for greater social interaction between hens || Increased risk of feather-peaking, fighting and cannibalism ||
 * Ability to express most natural behaviours, e.g. dust bathing, perching, food foraging || Increased risk of broken bones due to birds flying into objects ||
 * || Greater exposure to the weather and predators ||
 * || Greater labour requirements for monitoring birds and managing system ||
 * || Costs of production are increased resulting in increased price of eggs ||

Avoid deep penetration into the group’s flight zone [|Back to questions] [|Back to questions] Researchers (Fell & Shutt, 1988) described the pain associated with mulesing as the //greatest acute stressor// of all lamb marking procedures. So clearly it should not be a procedure that can be taken lightly. This does not mean that it should not be considered as an operation with obvious advantages.Anyone who has seen the graphic results of a blowfly strike on sheep will be acutely aware of the pain and stress that the option of not mulesing Merino sheep may result in. So while progress is slow and we edge towards viable alternatives to mulesing, for many, mulesing will remain a necessary evil. If mulesing is to be a part of the management strategies to assist in the control of flystrike then attention needs to be given to reduce the pain and stress caused on each animal that is mulesed.Mulesing should be carried out by skilled operators, using appropriate instruments that are sharp and cleaned.It is important that only those lambs that have wrinkles in the breech area should be mulesed. Each farmer should select animals for breeding that are more plain-bodied and individuals that are excessively wrinkly or are struck more frequently should be culled.Ideally lambs should be mulesed at 4 – 6 weeks of age as research has shown that younger animals recover more quickly than older animals. Lambs should be mulesed in small groups so that they can be returned to their mothers and released onto pastures as quickly as possible. This reduces the time lambs are in dirt yards where the risk of infection is increased.To further reduce the risk of disease, lambs should be vaccinated and the wounds sprayed with antibacterial fly powder or spray.
 * Make a judgement about which system you support, considering the welfare of the hens, the cost of eggs to consumers and the support provided for egg producers.**//You need to make your own judgement about which system you support and then justify your judgement by discussing the advantages and disadvantages of each system. An example of such an answer is below.//There are quite clearly advantages and disadvantages of each of the systems but I favour the free range system. A free range system provides hens with the freedom to move and express their natural behaviours. This does expose the hens to increased risk of disease, predation and extremes of weather that hens in a caged environment are protected from. Life in a flock of birds also involves risks related to social hierarchy with free range and barn systems exposing individuals to cannibalism, feather pecking and intimidation. Cage systems control these factors.These are all issues that animals in natural environments experience. Producing eggs in a cage system decreases the quality of life of the hen in terms of movement, nesting, perching and scratching but increases it through protecting from disease and predation. I think that quality of life for the hens is more important than quantity.Egg producers using a free range system have increased costs because of the increased time required to monitor and manage the system. Eggs produced from this system cost the consumer more than eggs produced in the cage system. For free range producers to remain viable consumers must be prepared to pay more for their eggs.In the competitive market it is more difficult for free range producers to maintain a consistent supply throughout the year and be profitable. Consumers need to understand the issues and be prepared to pay more and tolerate any fluctuations in supply.I am prepared to pay more for the eggs I buy to ensure that hens can have a better quality of life. Unfortunately not all consumers may be prepared to make this decision
 * Better cattle management by understanding their behavioural characteristics**
 * 1) **When cattle are in a race, describe how the handler should behave/act to make them move forward.**To make cattle move forward in a race, the handler should walk in the opposite to direction to the way the cattle are facing.
 * 2) **When cattle are in a race, describe how the handler should behave/act to make them move backward.**To make cattle move backwards in a race, the handler should walk in the same direction to the way the cattle are facing.
 * 3) **Outline four basic principles that can be used to help move cattle in open paddocks**.
 * The handler should alternate moving into the collective flight zone and out of the collective flight zone. Alternating pressure is more effective than continuous pressure.
 * Move in straight lines and do not circle around animals.
 * Do not chase individual animals as they will move back into the herd.
 * Work the group point of balance.
 * Avoid the blind spot behind the animal.
 * If cattle baulk at an object or shadow, wait for the leader to cross it, then allow the rest of the herd to follow.
 * Try to keep the animals calm and moving at a walk.
 * Legal, welfare and ethical issues related to mulesing in sheepAnswers**
 * Legal requirements**
 * 1) **What limitations are placed on the age of sheep for mulesing?**In NSW it is illegal to mules sheep over the age of 12 months, unless under veterinary supervision.
 * 2) **What is the ideal age of sheep for mulesing?**Ideally mulesing should be carried out at marking time when they are 4-6 weeks old.
 * 3) **Is anaesthetic required before mulesing?**Anesthetic is only required for the mulesing of sheep after the age of 12 months and the mulesing must be performed by a veterinarian.
 * 4) **Are all sheep breeds mulesed?**Only sheep of the Merino breed are mulesed. Other breeds tend to be more plain-bodied and therefore do not have the wrinkles of skin that provide favourable sites for the blowflies to infest. Figures indicate that approximately 70% of all Merino sheep are mulesed.
 * Animal welfare issues**
 * 1) **Why is mulesing routinely carried out?**The blowfly, has been documented, as the most detrimental parasite affecting the Australian sheep and wool industry. Blowflies seek to lay eggs in the damp wool of sheep. The flesh eating maggots that hatch have the potential to cause wounds that can lead to blood loss, septicaemia and death.Mulesing is the surgical removal of skin around the breech and tail area of lambs to reduce the chance of breech and tail fly strike. The resulting skin is tighter and remains more clean and dry than if not mulesed.By removing the skin folds from around the breech and tail area, a potential site for blowflies to lay their eggs is removed, thus drastically reducing the incidences of blowfly strike.An integrated pest management (IPM) approach is required to control blowfly strike. This involves the husbandry activities of tail docking, jetting and routine checking of flocks to locate and treat affected animals, as well as mulesing.Blowflies are usually most active after rain when the temperatures are warm to hot.
 * 2) **What are some of the risks to the animal due to mulesing?**Because mulesing results in quite a large open wound there is the risk of infection and flystrike.
 * 3) **List some practices that help to reduce the stress on animals caused by the operation of mulesing.**To reduce the chance of flystrike, the operation should be carried out during periods of low fly numbers, i.e. during the cooler months or dry periods. The wound should be sprayed with an antibacterial fly powder or spray to reduce the chance of infection and deter flies from the wound area.To further reduce the chance of infection, the operation should be carried out with sharp, clean implements. Lambs should be vaccinated to reduce the chance of clostridial infections.Lambs should be marked and mulesed in small groups as this decreases the amount of time they are separated from their mothers, increases their ability to find their mothers and reduces the amount of time they are left in the yards where they suffer increased risk of infection.No matter what method is used it is important to have a skilled operator carrying out the mulesing. This increases the success rate and the efficiency of the operation. Increased efficiency leads to lambs back with their mothers more quickly and hence less stress on them.
 * 4) **Research is being carried out to find alternatives to mulesing. Briefly describe two alternatives that are currently being researched.**Much work is being done to select and breed sheep with bare breech and resistance to blowfly maggots. Ideally sheep should be smooth-skinned presenting many less sites that are likely to be struck. Although this alternative to mulesing will take a long period of time to achieve, it is likely to provide the best solution to the problem of flystrike.The Australian Wool Innovation is working on the development of plastic clips that can be applied to wrinkles in the breech. These act in a similar way to elastrator rings used for tail docking and castration, causing the excess skin of the breech area to be shed.The University of Adelaide has identified a protein that kills wool follicles and tightens the skin. Investigations are being carried out to development of an application for automated delivery of the protein into the breech area.
 * Ethical issues**
 * 1) **While mulesing causes stress to the animals and considerable work for the producer, the advantages of it are obviously seen to outweigh both of these. Write your thoughts about mulesing and how the advantages must be considered against the disadvantages. Make sure you consider:**
 * **the pain and stress on the animal**
 * **the reasons for carrying out mulesing**
 * **possible outcomes if mulesing was not carried out**
 * **practical alternatives to mulesing**
 * **the advantages to the producer**
 * **your background and own personal experiences (these help form your opinions).**


 * Experimental Analysis and Research in Plant and Animal Production **


 * Glossary of Key HSC Verbs **
 * // M //****// any students who have attempted to achieve high marks whilst studying for the HSC are often disappointed at their result because they: //**
 * Are determined to prove how much they’ve learned, regurgitating learned material, and ignoring the question.
 * Only answer part of the question, even though the examiner may have required several things to be done in order to get full marks.
 * Answer the question they hoped would be there, rather than the one that actually is.
 * Misinterpret the //verb.//

By carefully reading exam/assessment questions and becoming more familiar with the following HSC terms you will improve your ability to both understand and address exactly what each question is asking.
 * Remember: ** That you are not marked on what you know, but how much you know that is relevant to the question.

Account for: state reasons for, report on. Give an account of: narrate a series of events or transactions Identify components and the relationship between them; draw out and relate implications Use, utilise, employ in a particular situation Make a judgement about the value of Make a judgement of value, quality, outcomes, results or size Ascertain/determine from given facts, figures or information Make clear or plain Arrange or include in classes/categories Show how things are similar or different Make; build; put together items or arguments Show how things are different or opposite Add a degree or level of accuracy depth, knowledge and understanding, logic, questioning, reflection and quality to (analyse/evaluate) Draw conclusions State meaning and identify essential qualities Show by example Provide characteristics and features Identify issues and provide points for and/or against Recognise or note/indicate as being distinct or different from; to note differences between Make a judgement based on criteria; determine the value of Inquire into Relate cause and effect; make the relationships between things evident; provide why and/or how Choose relevant and/or appropriate details Infer from what is known Recognise and name Draw meaning from Plan, inquire into and draw conclusions about Support an argument or conclusion Sketch in general terms; indicate the main features of Suggest what may happen based on available information Put forward (for example a point of view, idea, argument, suggestion) for consideration or action Present remembered ideas, facts or experiences Provide reasons in favour Retell a series of events Express, concisely, the relevant details Putting together various elements to make a whole
 * Account **
 * Analyse **
 * Apply **
 * Appreciate **
 * Assess **
 * Calculate **
 * Clarify **
 * Classify **
 * Compare **
 * Construct **
 * Contrast **
 * Critically (analyse/evaluate) **
 * Deduce **
 * Define **
 * Demonstrate **
 * Describe **
 * Discuss **
 * Distinguish **
 * Evaluate **
 * Examine **
 * Explain **
 * Extract **
 * Extrapolate **
 * Identify **
 * Interpret **
 * Investigate **
 * Justify **
 * Outline **
 * Predict **
 * Propose **
 * Recall **
 * Recommend **
 * Recount **
 * Summarise **
 * Synthesise **

=** AGRICULTURE TERMS **= = = = =