Explanation:
(a) Characteristics considered during selection of livestock for breeding;

Productivity /yield/prolificacy
Resistance to diseases
Quality of product
Early maturity/growth rate
Adaptation to climatic conditions
Good mothering ability
Male with high libido
Resistance to diseases
Age of the animal
Body form /conformation of livestock/body shape
Economy in use of feed/feed conversion efficiency


(b) Characteristics of Zebu cattle;

Humped
Large ears
Horned
Resistant to trypanosomiasis
Large dewlaps
Large size
Tolerant to drought


(c) Functions of water in farm animals;

Helps in the excretion of waste products
Lubricates joints
Helps in blood circulation
Helps in salivation
Helps to maintain cell turgidity/body shape
Osmoregulation
Aids in digestion of feed/nutrient dissolution
Needed for transporting nutrients to various parts of the body
Helps to regulate body temperature/wallowing in pigs/body cooling/homeostasis
Important constituents of milk, egg and meat


(d) Nutritional disorders in farm animals;

Rickets
Pellagra
Scurvy
Anaemia
Bloat
Milk fever
Osteomalacia
Osteoporosis
Grass tetany
Constipation
Diarrhoea
Alopecia
Pica
Cannibalism
Night blindness