Hurwitz S, Plavnik I, Bengal I, Bartov I
Institute of Animal Science, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel.
Poult Sci. 1988 Mar;67(3):420-6. doi: 10.3382/ps.0670420.
Growth, feed efficiency, and carcass fat were evaluated in turkeys fed diets in which added fat varied, holding energy or the calories:protein ratio constant. In the 1 to 3-wk-old turkey, growth and feed efficiency increased with dietary energy, but did not change significantly when fat was added isocalorically. The 12 to 14-wk-old turkey responded with improved growth and feed efficiency when dietary fat was added either isocalorically or with increasing energy density. However, the response to the isocaloric fat addition was smaller in magnitude than the response when fat was added without calorie adjustment. No difference could be detected in 12 to 15-wk-old turkeys in the performance response to tallow and soybean oil. Carcass fat deposition generally increased with dietary fat supplementation, regardless of the caloric change. The results suggest that in the midterm of development of the growing turkey, dietary fat per se affects growth, feed efficiency, and carcass fat. Growth and feed efficiency responses to nutrient density occur in both young and older birds.
蛋白质比恒定的日粮的火鸡进行生长性能、饲料效率和胴体脂肪评估。在1至3周龄的火鸡中，生长性能和饲料效率随日粮能量增加而提高，但等热量添加脂肪时无显著变化。在12至14周龄的火鸡中，等热量添加或增加能量密度添加日粮脂肪时，生长性能和饲料效率均有所改善。然而，等热量添加脂肪时的反应幅度小于不调整热量添加脂肪时的反应。在12至15周龄的火鸡中，未检测到对牛脂和大豆油的生产性能反应有差异。无论热量变化如何，胴体脂肪沉积通常随日粮脂肪添加量增加而增加。结果表明，在生长中火鸡发育中期，日粮脂肪本身会影响生长、饲料效率和胴体脂肪。幼龄和老龄火鸡对营养密度的生长性能和饲料效率反应均会出现。
