Methods Of Animal Improvement

Overzicht

A herder near Sokoto wants calves that grow faster without losing the White Fulani's famous heat tolerance. A poultry keeper in Ibadan wants birds that lay like an exotic hybrid but survive a Nigerian backyard on local feed. Neither farmer can wish a better animal into existence. What they can do is choose who mates with whom, generation after generation, and that single choice is the whole of animal improvement.

In this lesson you will meet the four methods examiners expect you to know inside out: selection, crossbreeding, inbreeding and outbreeding. You will learn what each one does to a herd's genes, work through realistic farm scenarios that decide which method fits which goal, and master the advantage and disadvantage of each, the exact comparison WAEC sets almost every year.

Doelstellingen

  1. State the methods of animal improvement
  2. Explain selection as a method of animal improvement
  3. Explain crossbreeding as a method of animal improvement
  4. Distinguish between inbreeding and outbreeding
  5. Explain the advantages and disadvantages of each method of animal improvement

Lesnotitie

Two farmers each want a better herd. One mates his best cow to his best bull. The other buys in an exotic bull to cross onto his local cows. Both practise animal improvement, with different tools and risks. A breeder who cannot name the method used cannot predict the next generation, and an examiner will ask exactly that.

Lesevaluatie

Gefeliciteerd met het voltooien van de les op Methods Of Animal Improvement. Nu je de sleutelconcepten en ideeën, het is tijd om uw kennis op de proef te stellen. Deze sectie biedt een verscheidenheid aan oefeningen vragen die bedoeld zijn om uw begrip te vergroten en u te helpen uw begrip van de stof te peilen.

Je zult een mix van vraagtypen tegenkomen, waaronder meerkeuzevragen, korte antwoordvragen en essayvragen. Elke vraag is zorgvuldig samengesteld om verschillende aspecten van je kennis en kritisch denkvermogen te beoordelen.

Gebruik dit evaluatiegedeelte als een kans om je begrip van het onderwerp te versterken en om gebieden te identificeren waar je mogelijk extra studie nodig hebt. Laat je niet ontmoedigen door eventuele uitdagingen die je tegenkomt; beschouw ze in plaats daarvan als kansen voor groei en verbetering.

  1. Which method of animal improvement combines animals of two different breeds to produce offspring that may outperform both parent breeds? A. Selection B. Crossbreeding C. Inbreeding D. Outbreeding Answer: B
  2. Mating a sire to his own daughter is an example of: A. Crossbreeding B. Outbreeding C. Inbreeding D. Selection Answer: C
  3. The improved performance often shown by the first-cross offspring of two different breeds is called: A. Inbreeding depression B. Hybrid vigour C. Genotype drift D. Betterment Answer: B
  4. A herd that has been mated among close relatives for several generations begins to show smaller litter sizes and weaker offspring. This is best described as: A. Hybrid vigour B. Inbreeding depression C. Heterosis D. Selection response Answer: B
  5. Which method of animal improvement chooses the best-performing animals within a single breed as parents of the next generation? A. Crossbreeding B. Outbreeding C. Selection D. Hybridisation Answer: C

Eerdere Vragen

Benieuwd hoe eerdere vragen over dit onderwerp eruitzien? Hier zijn een aantal vragen over Methods Of Animal Improvement van voorgaande jaren.

Vraag 1 Verslag

(a) Explain each of the following terms as used in the slaughtering of farm animals:
(i) scalding 
(ii) singeing:
(iii) evisceration.

(b) Name four agents involved in the marketing of farm animals and animal products

(c) State five marketing functions that could be performed to facilitate the sale of chicken and eggs.

(d) Name three stages in the life cycle of a roundworm.

(e) Mention two methods of animal improvement.