Theory question 108
Animal Improvement(a) Write short notes on the following systems of breeding: (i) In-breeding; (ii) Line-breeding; (iii) Cross-breeding.
(b) State three methods of collecting semen from a proven male for use in artificial insemination.
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(a)(i) In-breeding: mating closely related animals (e.g. brother × sister, sire × daughter); fixes traits but may bring out harmful recessive genes and reduce vigour
(ii) Line-breeding: a mild form of inbreeding that keeps a line related to one outstanding ancestor, to concentrate its good genes
(iii) Cross-breeding: mating animals of different breeds; gives hybrid vigour and combines good traits of both breeds; used to form new breeds
(b) Any three: artificial vagina; electro-ejaculation; massage (of the ampullae/abdomen, used in poultry and bulls); collection from the vagina of a mated female
Short note for each system; name three collection methods.