Animal Science and Livestock Production
Domain 2: Animal Science and Livestock Production
This domain tests the biology and management of farm animals: digestion, nutrition, breeding, housing, health and products. In Malawi, expect local cattle, goats, pigs and village chickens alongside improved breeds.
Core rules and concepts
- Digestive systems: ruminants (cattle, goats, sheep) ferment feed in the rumen; non-ruminants (pigs, poultry) rely on simple stomach digestion. Rations differ accordingly.
- Feed classes: roughages (grass, legume hay, crop residues), concentrates (maize bran, oilseed cake), minerals and vitamins. Dry matter intake limits production.
- Breeding: the oestrous cycle in cattle is about 21 days; heat lasts roughly 12–18 hours. Signs include standing to be mounted, mucus discharge and restlessness.
- Performance measures: feed conversion ratio (FCR) = feed consumed ÷ liveweight gain; daily gain = weight change ÷ days.
Worked example
A pen of pigs consumes 120 kg of feed over 30 days and gains 30 kg liveweight. FCR = 120 ÷ 30 = 4.0 kg feed per kg gain. If feed costs MK 800/kg, feed cost per kg gain = 4.0 × 800 = MK 3,200. The reasoning: FCR compares feed input with output; lower FCR is better. Do not confuse FCR with feed efficiency (gain ÷ feed), which would be 0.25.
Traps that cost marks
- Giving ruminant rations to pigs or poultry.
- Confusing oestrous cycle length with heat duration.
- Using total feed instead of dry matter when comparing feeds.
- Ignoring mortality and culling when calculating herd performance.