Theory question 107
Animal Health(a) Define each of the following terms as used in animal health: (i) pests; (ii) pathogens; (iii) vectors; (iv) parasites.
(b) Give one example of an organism described by each of the terms in 7(a) above.
(c) State four steps involved in silage making.
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(a)(i) Pests: animals that harm livestock or reduce their productivity, e.g. by attacking or disturbing them.
(ii) Pathogens: disease-causing organisms (bacteria, viruses, fungi, protozoa).
(iii) Vectors: organisms that carry disease organisms from one animal to another.
(iv) Parasites: organisms that live on or in a host and feed on it, harming it.
(b) Pest – rat/tick/fly; pathogen – Bacillus anthracis/virus of rinderpest; vector – tsetse fly (or tick); parasite – tapeworm/liver fluke/tick/louse.
(c) Cut the green forage at the right stage; chop it into short pieces; fill the silo and compact it to remove air (add molasses if needed); seal it airtight and leave it to ferment for about 3–6 weeks.
Silage steps: cut, chop, compact, seal.