补充不同处理蛋氨酸和小肽及对奶牛产奶性能和营养物质消化率的影响

为研究蛋氨酸和小肽及其过瘤胃保护处理对奶牛生产性能和营养物质消化率的影响,本试验选择产奶量、膘情、胎次、泌乳阶段接近的泌乳奶牛12头,随机分为4组,试验1、2组添加小肽17．5 g／d·头,试验3、4组添加蛋氨酸10．0 g／d·头,其中,试验2组和4组均添加经脂肪包被的小肽或蛋氨酸。通过饲养试验和消化代谢试验分析和测定了各试验牛的生产性能及各营养物质的消化率。结果表明各组间奶牛产奶量、乳蛋白、乳脂率和饲料粗蛋白消化率无显著差异(P>0．05),但试验2组的产奶量、乳成分及粗蛋白消化率相对较高;试验1、2、4组的奶料比显著高于试验3组(P<0．05),试验4组的Ca、P消化率显著高于其它各组(P<0．05)。综合分析表明添加小肽的效果优于添加氨基酸的效果,过瘤胃保护处理有利于奶牛生产性能和营养物质消化率的提高,其中以试验2组(保护性小肽)的效果最好。

Effect of Supplemental Peptides and Methionine With or Without Rumen Bypass on Milk Performance and Nutrient Digestibility in Lactating Cows

Twelve lactating cows with the similar lactation period and milk production were randomly divided into 4 groups, group 1 and 2 were supplemented 17. 5 g/d peptide, group 3 and 4 were supplemented 10. 0 g/d methionine, the peptide or methionine for group 2 and 4 were ruminally protected by fat. The milk performance and nutrient digestibility of each group were determined in the feeding trial. The results showed that there was no significant effect of supplementation on milk yield?protein percentage, fat percentage and protein digestibility with a relatively high values for group 2 (P>0. 05); the milk to feed ratios of group 1,2, and 4 were significantly greater than that of group 3 (P<0. 05), calcium and phosphorous digestibility in group 4 was significantly greater than in other groups (P<0. 05). In conclusion, the better effect of peptide supplementation was noted, and the rumen bypass treatment could increase milk performance and nutrient digestibility with the best results obtained in group 2.