AFU Common Entrance Exam key terms

The branch of agriculture that studies the science and practice of growing field crops and managing soil. It covers crop selection, planting, nutrition, irrigation, and harvesting to maximise yield and quality.

The ability of soil to supply essential plant nutrients in adequate amounts and correct proportions for healthy crop growth. It depends on nutrient content, pH, organic matter, texture, and microbial activity.

The planned sequence of growing different crops on the same land across seasons. It reduces pest and disease buildup, improves soil structure, balances nutrients, and helps control weeds.

A substance applied to soil or plants to supply nutrients that improve growth and yield. Fertilizers may be organic, such as manure or compost, or inorganic, such as urea, and are described by their nitrogen, phosphorus, and potassium content.

The decaying plant and animal residues present in soil. It improves water retention, structure, and nutrient-holding capacity, and it feeds the soil organisms that recycle nutrients for crops.

A decision-based approach to controlling pests that combines biological, cultural, physical, and chemical methods. Pesticides are used only when monitoring shows they are needed, reducing cost and environmental harm.

The artificial supply of water to crops when rainfall is insufficient or irregular. Common systems include furrow, sprinkler, and drip irrigation, and scheduling depends on crop water needs and soil moisture.

The reduction in quantity or quality of a crop between harvest and consumption. Causes include poor drying, inadequate storage, pests, mould, and rough handling, and losses are often high in tropical smallholder systems.

An infectious disease that can pass from animals to humans, either directly or through food, water, or vectors. Examples include rabies, brucellosis, and salmonellosis, and control requires cooperation between veterinary and public health services.

The administration of a vaccine to stimulate protective immunity against a specific pathogen. In livestock, routine vaccination reduces mortality and is central to controlling diseases such as foot-and-mouth disease and Newcastle disease.

A disease that must be reported to the authorities by law when it is suspected or confirmed. Reporting allows rapid investigation and control, and failure to report is usually an offence for veterinarians and farmers.

The enforced isolation of animals, animal products, or plants for a period to prevent the spread of disease or pests. It is used at borders, in farms during outbreaks, and before introducing new stock into a herd.

A hoofed mammal with a multi-chambered stomach that ferments plant fibre with the help of microbes. Cattle, sheep, and goats are ruminants, and their nutrition depends heavily on forage and rumen health.

The total feed given to an animal over a stated period, balanced to meet its energy, protein, mineral, and vitamin needs. A well-formulated ration supports growth, milk production, or reproduction without waste.

The first milk produced after birth, rich in antibodies and nutrients. Newborn animals must receive it within the first hours of life to gain passive immunity, since they are born with little protection against infection.

Inflammation of the udder, usually caused by bacterial infection entering through the teat canal. It reduces milk yield and quality, and control relies on hygiene, teat dipping, and correct milking machine maintenance.

Traces of an antibiotic remaining in milk, meat, or eggs after treatment. Residues can harm consumers and disrupt dairy processing, so treated animals must be withheld from the food chain for the stated withdrawal period.

The farming of aquatic organisms such as fish, shellfish, and seaweed under controlled conditions. It includes ponds, cages, and tanks, and success depends on water quality, stocking density, feed, and disease management.

The number or biomass of fish held per unit volume or area of water. Too high a density causes oxygen depletion, stress, and disease, while too low a density wastes pond or cage capacity.

The amount of oxygen gas present in water and available to aquatic animals for respiration. Low levels cause stress and death, and oxygen is replenished by aeration, photosynthesis, and water exchange.

The addition of organic or inorganic nutrients to a fish pond to encourage plankton growth. Plankton forms natural food for fish and can reduce feed costs, but over-fertilization risks oxygen depletion.

A young fish at a stage after the fry phase, large enough to be stocked into ponds or cages. Fingerlings are produced in hatcheries and their size and health strongly influence survival and final yield.

Non-target organisms caught accidentally during fishing, including undersized fish, turtles, and seabirds. Bycatch wastes resources and harms ecosystems, so gear modifications and closed areas are used to reduce it.

The largest catch that can be taken from a fish stock year after year without reducing the stock's ability to replenish itself. It guides quotas and fishing effort in managed fisheries.

The science and practice of establishing, tending, and harvesting forest stands. It covers nursery work, planting, thinning, and regeneration to meet timber, fuelwood, and conservation objectives.

The establishment of trees on land that has not recently carried forest. It is used to restore degraded land, protect soil, and store carbon, and requires matching species to site conditions.

A land-use system in which trees are grown together with crops or livestock on the same land. It diversifies income, improves soil, and provides shade, but requires careful management of competition for light and water.

The selective removal of some trees from a stand to reduce competition and favour the growth of remaining trees. It improves timber quality, allows light to reach the forest floor, and provides intermediate income.

An area of land that drains all rainfall into a common river, lake, or groundwater body. Managing watersheds protects water supply, reduces flooding and erosion, and links forest cover to downstream users.

The uptake and storage of atmospheric carbon dioxide by plants, soils, and oceans. Growing forests capture carbon in wood and soil, which is a key argument for forest conservation and reforestation.

The permanent removal of forest cover, usually through clearing for agriculture, logging, or settlement. It causes soil erosion, biodiversity loss, and increased carbon emissions, and is countered by reforestation and better land-use planning.