Ferket P R, Sell J L
Department of Animal Science, Iowa State University, Ames 50011.
Poult Sci. 1989 May;68(5):676-86. doi: 10.3382/ps.0680676.
The effect of early protein (Pr) nutrition on compensatory growth and leg weakness of turkey toms was studied. Four levels of dietary Pr [100, 80, 70, or 60% of National Research Council (NRC) recommendations in 1984] were fed ad libitum in isocaloric diets from 1 to 6 wk of age. Subsequently, the four treatment groups were fed a common diet within age periods according to NRC (1984) Pr levels. As the level of Pr decreased, body weight at 6 wk decreased (2.23, 1.94, 1.63, and 1.39 kg, respectively, P less than .005) and 1 to 6-wk feed:grain ratios increased. Weight gains from 6 to 20 wk of age were the same for all treatment groups. Thus, a significant carry-over effect of Pr on body weight was still evident at 20 wk of age (15.5, 15.2, 14.9, and 14.5 kg, respectively, P less than .005). Feed consumption decreased linearly through 16 wk of age as Pr decreased. Feed:gain ratios from 6 to 20 wk of age decreased (3.25, 3.20, 3.14, and 3.13, respectively, P less than .05), and Pr consumption:gain ratios from 1 to 20 wk decreased (.596, .551, .546, and .543, respectively, P less than .005) as the level of Pr decreased. However, the cumulative feed:gain ratio from 1 to 20 wk of age was not affected by Pr. The 60 or 70% level of dietary Pr resulted in 60% fewer toms with severe leg weakness at 18 wk of age than the 100% level of dietary Pr. Toms have limited ability for compensatory weight gain within the realimentation time allowed, regardless of the level of Pr fed from 1 to 6 wk. However, significant savings in dietary Pr and reduced leg weakness may be economically beneficial when Pr is restricted to 70% of the 1984 NRC recommendations during early growth.
研究了早期蛋白质（Pr）营养对火鸡公雏补偿生长及腿部无力的影响。在1至6周龄期间，以等热量日粮随意饲喂四种水平的日粮Pr[分别为1984年美国国家研究委员会（NRC）建议量的100%、80%、70%或60%]。随后，四个处理组在各年龄段内按照NRC（1984）的Pr水平饲喂普通日粮。随着Pr水平降低，6周龄时体重下降（分别为2.23、1.94、1.63和1.39千克，P<0.005），1至6周的料肉比增加。所有处理组6至20周龄的体重增加量相同。因此，Pr对体重的显著残留效应在20周龄时仍然明显（分别为15.5、15.2、14.9和14.5千克，P<0.005）。随着Pr水平降低，至16周龄时采食量呈线性下降。6至20周龄的料重比下降（分别为3.25、3.20、3.14和3.13，P<0.05），1至20周的Pr摄入量与增重比下降（分别为0.596、0.551、0.546和0.543，P<0.005）。然而，1至20周龄的累积料重比不受Pr影响。日粮Pr水平为60%或70%时，18周龄时腿部严重无力的火鸡公雏比日粮Pr水平为100%时少60%。无论1至6周饲喂的Pr水平如何，火鸡公雏在允许的再饲喂时间内补偿性增重的能力有限。然而，在早期生长阶段将Pr限制在1984年NRC建议量的70%时，日粮Pr的显著节省和腿部无力的减轻在经济上可能是有益的。
