去势公猪和小母猪对饲粮蛋白质或赖氨酸水平的反应

Response of barrows and gilts to dietary level of protein and lysine

利用２８头杜×哈去势公猪和小母猪在３０—９０ｋｇ体重阶段，研究两种饲粮对其生长性能、胴体性状和胴体组成的影响。试验前期饲粮１含粗蛋白１５％，赖氨酸０．７５％；饲粮２含含粗蛋白１６．５％，赖氨酸０．８０％；后期饲粮１含粗蛋白１３．５％，赖氨酸０．６５％，饲粮２含粗蛋白１５％，赖氨酸０．８０％。试猪采用小群趴卧、个体单栏饲喂方法进行肥育，于９０ｋｇ体重结束肥育并屠宰测定胴体性状和胴体组成。结果表明，饲粮２使屠宰年龄提前１０．６日（Ｐ＜０．０１），平均日增重提高１０７．４ｇ（Ｐ＜０．００１），耗料增重比降低０．３０（Ｐ＜０．０１），平均日采食量增加１１０ｇ（Ｐ＜０．０５），平均背膘厚降低０．４５ｃｍ（Ｐ＜０．０１），瘦肉率提高４．７６个百分点（Ｐ＜０．００１），脂肪率减少５．４１个百分点（Ｐ＜０．００１）；去势公猪较小母猪采食量高、生长速度快（Ｐ＞０．０５），小母猪的胴体瘦肉率较去势公猪高２．４５个百分点（Ｐ＜０．０５），脂肪率低２．４２个百分点（Ｐ＜０．０５），各生长性能、胴体性状和胴体组成均不存在显著的性别和饲粮间的工作效应。

pigs(intitially 30% kg BW)were used to determine effects of dietary level of protein and lysine on growth Performance, carcass characteristics and carcass composition in a 2×2 factorial arrangement.Protein(or lysine)level were 15%￣13.5%(0.75￣0.65)in diet Ⅰ and 16.5% ～ 15 % (0. 90%￣0.8%)in diet Ⅱ separately. Pigs were slaughtered until the weight of pigs reached 90 kg.Overall,pigs fed diet Ⅰ had increased ADG(P<0.001),gain:feed ratio (P<0.01)and CP accretion(P<0.001),but decreased backfat thickness(p<0.01)and lipid accretion P<0.001)compared with pigs fed diet Ⅱ.Gilts had increased CP accretion (P<0.05)and decrease lipid accretion(P<0.05),but exhibited a poorer(P>0.05)ADG compared with barrows.