Identify the condition: Milk Fever (Hypocalcaemia). (1 mark)
Category: Metabolic. (1 mark)
The Fix (Action): Inject Calcium (Calcium Gluconate). (1 mark)
The Location: It should be injected under the skin (subcutaneously). (1 mark)
The Reason: Injecting directly into the vein can be dangerous because it can stop the cow's heart if it goes in too fast. Under the skin is safer for a farmer to do in the paddock. (1 mark)
Identify the pest: Western Flower Thrip (WFT). (1 mark)
The Monitoring Tool: WFT are specifically attracted to the color blue. Yellow traps are for aphids/whiteflies, but blue is the most effective for detecting thrips early. (1 mark)
IPM Strategy (Biological): Predatory Mites (e.g., Neoseiulus cucumeris) particularly in protected crops in greenhouses such as strawberries or cucumbers or Orius tantillus (the species of pirate bugs used in Australia) these are effective outside as well as in greenhouses. (1 mark)
Identify the disease: Fungal Rust (e.g., Wheat Stem Rust or Leaf Rust). (1 mark)
Category: Microbial (Fungal). (1 mark)
Long-term Prevention: Look for a High Resistance rating (e.g., MR - Moderately Resistant or R - Resistant). (1 mark)
Why? A high resistance level means the plant's own DNA can fight off the fungus without needing as much chemical spray. (1 mark)
Identify the pest: Intestinal Worms (e.g., Barber's Pole or Black Scour Worm). (1 mark)
The Test (WEC): It is used to count the number of worm eggs in a sample of manure. This tells the farmer how "heavy" the worm burden is and if they actually need to use a chemical drench. (1 mark)
IPM Strategy (Cultural): Moving to a "clean" paddock (one that hasn't had sheep for a while) breaks the life cycle. It means the sheep aren't eating fresh larvae off the grass, this allows their bodies to recover. (1 mark)
Description: (1 mark) Mentioning animal welfare (pain) or economic loss (less meat/wool produced).
Prevention: (1 mark) Quarantine new stock or dry out the paddocks.
Control: (1 mark) Using a chemical foot-bath or paring (trimming) the hooves.
1 mark For stating that traps are used for monitoring/detection to determine the population size or "Action Threshold" before a pest becomes an economic problem.
1 Mark For explaining that they are hung within or just above the crop canopy where insects are active.
1 Mark For identifying that specific colours attract specific pests (e.g., Blue for Western Flower Thrips and Yellow for Aphids/Whiteflies).
1 mark For identifying that weeds act as a reservoir where pests and diseases survive between cropping seasons.
1 mark For explaining that removing these weeds physically disrupts the life cycle of the pest by removing their food source and shelter, preventing them from migrating into the main crop.
1 mark For identifying that Ladybirds are beneficial insects or natural enemies that provide biological control by eating pests like Aphids.
1 mark For explaining that many chemical sprays are non-selective or broad-spectrum, meaning they will kill the helpful ladybirds along with the pests.
1 mark For noting that if the ladybirds are killed, the pest population might rebound even faster because there are no longer any natural predators left to keep them in check.
1 mark For defining the economic threshold as the point where the cost of the damage caused by the pest is greater than the cost of the treatment.
1 mark For explaining that if the rust levels are below this point, spraying would result in a financial loss for the farm because the treatment costs more than the crop value it saves.
1 mark For noting that waiting prevents unnecessary chemical use, which protects the environment and reduces the risk of the fungus developing resistance.
1 mark For explaining that within any population, some aphids may have a natural genetic mutation that makes them immune to the spray.
1 mark For stating that these survivors breed and pass on those resistant genes to the next generation until the majority of the population is immune.
1 mark For suggesting the farmer rotate chemical groups by using a product with a different mode of action.
1 mark For suggesting an integrated approach, such as introducing beneficial insects like ladybirds to eat the resistant pests.
1 mark For explaining that a worm egg count allows the farmer to measure the actual parasite burden so they only treat sheep when the population reaches a risky level.
1 mark For explaining that paddock rotation moves sheep away from larvae on the grass, which breaks the life cycle of the worm by preventing re-infection.
1 mark For concluding that combining these two principles keeps the worm population low without relying solely on chemicals, which builds long-term resilience on the farm.
1 mark: For identifying that flickweed seeds can travel several metres when the pods explode.
1 mark: For explaining that this allows the weed to spread rapidly across many pots or garden beds in a confined space.
1 mark: For identifying that gorse thickets physically block livestock from accessing pasture, reducing the total grazing area.
1 mark: For identifying that gorse provides shelter for vertebrate pests like rabbits or foxes which further damage the land or attack livestock.
1 mark: For explaining that the green bridge refers to weeds that grow between cropping seasons.
1 mark: For explaining that removing these weeds stops them from setting seeds that would compete with next year's crop.
1 mark: For noting that it also removes the habitat for aphids and other pests that could carry viruses into the new crop.
1 mark: For describing the explosive seed dispersal mechanism where mature pods flick seeds several metres away.
1 mark: For explaining that this makes physical control difficult because plants must be removed before they flower, otherwise the act of pulling the weed can trigger the seeds to spread further into neighbouring pots.
Q2: Wild Radish
1 mark: For identifying direct competition, where the weed takes moisture and nitrogen away from the wheat, leading to lower yields.
1 mark: For identifying harvest contamination, where radish seeds are mixed with the grain, leading to price penalties at the delivery point.
1 mark: For mentioning the cost of control, such as the high price of herbicides or the need for extra machinery to clean the grain.
Q3: Gorse
1 mark (Biological): For suggesting the release of the gorse spider mite to reduce the vigour and seed production of the plants or for suggesting the introduction of goats to reduce the infestation..
1 mark (Physical): For suggesting the use of heavy machinery or mulching to clear the dense thickets and allow access for other treatments.
1 mark (Chemical): For suggesting the targeted application of herbicides on cut stumps or regrowth to ensure the root system is killed.
1 mark (Integration/Sustainability): For noting that combining these methods reduces the reliance on any single tool and helps restore the land for productive grazing while removing habitat for pests like rabbits.
Q1: Cultural Control
Answer should state that cultural control is the most cost-effective and sustainable method.
Answer should explain that it prevents the problem from starting, which reduces the need for more expensive or harmful controls later on.
Q2: Biosecurity
Answer should identify that weed seeds can easily hide in the mud and dust on tires or machinery.
Answer should explain that washing the tractor physically removes those seeds so they are not transported into a clean paddock.
Q3: Long-term Outcome
Answer should identify that the weed population will likely develop biological resistance to that specific chemical.
Answer should explain that the survivors of the spray will breed and pass on their resistant genes, eventually making the chemical useless.
Q 1: Explain why applying a pesticide at half the recommended dose might actually make the pest problem worse in the long run.
Answer should identify that a half-dose (sub-lethal dose) fails to kill the more robust or naturally tolerant individuals in the pest population.
Answer should explain that these surviving pests are then able to reproduce and pass on their tolerant or resistant genetic traits to the next generation, rapidly increasing the overall resistance of the population to that chemical.
Question 2: What is meant by the term "Selection Pressure" in the context of biological resistance?
Answer should define selection pressure as an external force (such as the repeated use of a specific herbicide or pesticide) that changes the reproductive success of individuals in a population.
Answer should explain that this pressure "selects" for the individuals with resistant traits by killing off the susceptible ones, leaving only the resistant organisms to form the basis of all future generations.
Question 3: Why is the livestock industry moving away from using antibiotics as a preventative measure?
Answer should identify that constant, low-level exposure to antibiotics (prophylactic use) creates a permanent selection pressure on bacteria.
Answer should explain that this leads to the development of "superbugs" or antibiotic-resistant bacteria, which means that when an animal actually becomes dangerously ill, the life-saving medicine may no longer work.
Q1: Biological Process
1 mark: For identifying that a small number of worms had a natural genetic mutation allowing them to survive the drench.
1 mark: For explaining that these survivors reproduced and passed on their resistant genes, eventually leading to a population that the chemical cannot control.
Q2: Double Knock Strategy
1 mark: For defining the strategy as using two different control methods (modes of action) on the same generation of pests.
1 mark: For providing a specific example, such as using a herbicide followed by a physical or different chemical control.
1 mark: For explaining that this ensures that any "Resistant" individuals that survived the first hit are caught by the second hit.
1 mark: For concluding that this prevents the resistant survivors from breeding and spreading their genes.
The Federal Border
Your answer should identify a prohibited item e.g., raw beef jerky or unpeeled fruit and links it to a specific threat e.g., foot and mouth disease or exotic fruit fly and identifies the potentially impacted industry, beef cattle, citrus growing, etc.
State Movement
Your answer should identify a movement restriction e.g., the Greater Sunraysia Pest Free Area and explains it is to protect local industries from pests like Queensland Fruit Fly.
The PIC System
Your answer should define a PIC as a unique code for a piece of land and explain its role in traceability—allowing the government to quickly track and contain a disease outbreak should one occur.
The Farm Gate
Your answer should list instructions e.g., "Stop," "Contact Owner," "Stay on Tracks" and explain that they prevent the accidental spread of weed seeds or pathogens by controlling visitor movement.
What is the primary role of the federal Biosecurity Act 2015?
To manage biosecurity risks at Australia's national borders by inspecting and controlling the entry of people, planes, ships, and goods from overseas.
Why is a farm biosecurity sign at the front gate considered a physical or cultural control measure?
It is cultural because changes the behaviour of people entering the property, and physical because it directs visitors to stay in specific areas, stopping the accidental spread of pests or seeds.
Explain why a contractor should wash their vehicle before moving from one farm to another.
Washing removes soil and plant debris that may be carrying weed seeds, fungal spores, or microscopic pests, preventing the contractor from accidentally transporting a problem from an infested farm to a clean one.
Q1: Federal vs. State
1 Mark: For identifying that the federal government (Biosecurity Act 2015) is responsible for national borders and international entry points.
1 Mark: For identifying that state legislation (CaLP Act) manages declared noxious weeds and pest animals
Q2: Reporting
1 Mark: For identifying the action: the farmer must report the unusual pest to state authorities or the emergency hotline.
1 Mark: For the explanation: early reporting allows for a rapid response, which can prevent the pest from spreading and causing massive economic damage to other farmers and/or the industry as a whole.
Q1: To get 4 marks, you must explain that the repeated use of the same herbicide created a high selection pressure. The only surviving pests have a natural genetic resistance and, if not killed now, they will reproduce, passing that resistance to the next generation.
Q2: To get 4 marks, you must name a specific second "hit" (e.g., "following the spray with a mechanical cultivation" or "releasing a biological predator after the spray residue has gone"). You must explain why this second method is effective against the resistant survivors.
Q3: To get 2 marks, you must correctly name the Biosecurity Act 2015 and a specific action (e.g., "implementing a strict vehicle wash-down" or "locking all boundary gates and installing biosecurity signage").