Submitted to: World Congress of Genetics Applied in Livestock Production
Publication Type: Proceedings
Publication Acceptance Date: 5/1/2002
Publication Date: 8/1/2002
Citation: Dzakuma, J.M., Risch, .E., Blackburn, H.D. 2002. Goat growth model: genotype x nutritional environmental interactions. World Congress of Genetics Applied in Livestock Production. 31:237-240. Interpretive Summary: Growth, feed efficiency and body composition differences between goat breeds are not well documented. Therefore, goat producers do not have complete information when deciding which breed of goat they should use in their production system. We evaluated Spanish, Tennessee Stiff-legged and Boer goat breeds for growth, body composition and feed efficiency on three different diets (ad libitum, 85% and 70% of ad libitum). Boer and Tennessee Stiff-legged goats were equal for lean meat production and significantly greater than the amount of lean produced by Spanish goats.
Technical Abstract: Studies were conducted using three goat populations: the Boer (BR), the Spanish (SP), and the Tennessee Stiff-legged (TS) breeds, maintained at the International Goat Research Center. The goats were fed three levels: 100%, or (ad libitum) 85% and 70% of ad lib, of the same ration containing 18% CP and 65% TDN. Bi-weekly growth weights and daily feed intake and orts were collected until yearling age. In 1997/98 trial, only the SP and TS breeds were represented. Weights of goats maintained at the 85% and 70% levels were similar and differed significantly (P<.05) from the weight of goats maintained at the 100% level. Feed intake in intermediate sized SP (67.7 kg) was equal to (P>.05) that of small sized TS (66.7 kg) at 13 mo. From 2000/01 trial, the TS deposited, virtually the same amount of lean meat mass as the BR, and significantly higher (P<.01) lean meat mass than the SP. At 6 mo slaughter, lean-to-bone ratios (leanness indicator) were: TS=3.63, BR=3.26 and SP=2.56. Knowledge of the interaction between feed intake, genotype and body composition changes will help characterize growth curves in goats.