(a) Explain the term animal nutrition, [2 marks] (b) State four functions of oestrogen in animal reproduction [4 marks] (c) Explain each of the following me...

Answer Details

(a) Animal nutrition

Animal nutrition is the branch of animal science concerned with the intake, digestion, absorption and utilisation of food nutrients (carbohydrates, proteins, fats, vitamins, minerals and water) by farm animals for growth, maintenance, reproduction and production.

(b) Four functions of oestrogen in animal reproduction

1. It brings about the signs of heat (oestrus) and the sexual receptivity of the female.
2. It promotes the development of the female secondary sexual characteristics.
3. It stimulates growth and repair of the lining of the uterus (endometrium) in readiness for the fertilised egg.
4. It aids development of the mammary (milk) glands and the birth canal for parturition.

(c) Methods of animal improvement

(i) Selection: Choosing and keeping for breeding only those animals with the most desirable traits (high milk, fast growth, disease resistance) while culling inferior ones, so that good genes are passed to the offspring.

(ii) Breeding: Deliberate mating of selected animals to combine or fix desirable characters. It includes in-breeding, out-breeding, cross-breeding and up-grading to produce superior offspring.

(iii) Introduction: Bringing in improved breeds or stock from another area or country to replace or upgrade the local, lower-yielding animals.

(d) Ornamental plants

Ornamental plants are plants grown mainly for their beauty, that is for the decoration of homes, gardens, offices and surroundings because of their attractive flowers, leaves, form or scent, rather than for food.

(e) Four vegetative methods of propagating ornamental plants

1. Stem cuttings
2. Layering
3. Budding
4. Grafting (also division of clumps/suckers)