This question was fairly attempted by the candidates. In 4(a), most of the candidates were unable to define the term animal improvement but most of them were able to state the advantages and disadvantages of introduction as a method of animal improvement as required in 4(b).
In 4(c)(i-iv), although, most of the candidates were able to explain in-breeding and line breeding, majority of them could not explain cross breeding and out breeding. More so, in 4(d), majority of the candidates were able to complete the table indicating the name of mature female sheep, pig and rabbit but most of them could not give the gestation periods (days) of sheep, pig and rabbit.
The expected answers include:
(4) (a) Definition of animal improvement
It refers to means/techiques of developing/breeding/producing animals of better
traits/characters over the existing ones /parents
OR
It is a means/technique of introduction/selection/breeding of animals
with better/outstanding traits/character/genes/allele over the existing ones
(c) Explanation of the terms
- Cross breeding
- It is the mating of proven quality animals from
different breeds but the same species e.g. Muturu x White
Fulani.
- It leads to production of heterosis/hybrid vigour
- Out breeding
- It is the mating of unrelated animals of the same breed
- It recovers certain traits that may have been lost due to
other breeding methods.
- New traits are introduced in the offspring/young ones
(d) Completion of the table
Farm animal |
Gestation period (days) |
Sheep |
140-150 |
Pig |
113-115 |
Rabbit |
28-32 |
|