(a) Explain briefly three systems of mating in livestock management. [6 mark ] (b) Draw and label the digestive tract of a hen [7 mark ] (c) Give five reaso...

Answer Details

(a) Three systems of mating in livestock management

Stud (hand) mating: A proven sire is kept in a stud, and each dam that comes on heat is brought to him for a controlled, supervised service; the dam is then taken away. The farmer decides exactly which male serves which female, so parentage and records are accurate.

Pen mating: One selected male is placed in a pen together with a group of females that are on heat, and he is allowed to serve them freely within that pen. It is easier to manage than hand mating while still keeping the sire known.

Flock (pasture) mating: Both the sires and the dams are turned out together on the range or pasture and allowed to move about and mate freely at will. It needs little labour, but the exact parentage of the offspring is uncertain.

(b) Labelled digestive tract of a hen

Food passes through the alimentary canal of the hen in the following order:

beak (mouth) → oesophagus → crop → proventriculus (true stomach) → gizzard → small intestine (duodenum and ileum) → caeca → large intestine (rectum) → cloaca → vent.

The liver, gall bladder and pancreas are associated glands that pour their secretions into the small intestine to aid digestion. The diagram below shows these parts fully labelled and in their correct order.

(c) Five reasons why ornamental plants are important

1. They beautify the environment - homes, offices, gardens and roadsides - and are widely used in landscaping.
2. They are a source of income and employment through the florist and horticultural trade (sale of flowers, bouquets, wreaths and potted plants).
3. They are used to demarcate boundaries and, when planted as hedges, serve as windbreaks and shelter belts.
4. They provide shade, help purify the air and reduce noise pollution around buildings and roads.
5. They have educational, recreational and medicinal value, and some promote tourism and earn foreign exchange for the country.