机构地区: 南京农业大学动物科技学院
出 处: 《南京农业大学学报》 2006年第3期54-58,共5页
摘 要: 选用16头泌乳中期荷斯坦奶牛按拉丁方设计进行试验,研究饲粮中补充0、8、12和16g·d^-1过瘤胃蛋氨酸对奶牛产奶量、乳成分以及血液氨基酸含量的影响。结果表明,与对照组相比,补饲过瘤胃蛋氨酸能够提高奶牛乳蛋白、乳脂率和酪蛋白水平。补饲过瘤胃蛋氨酸对产奶量较高(〉22kg·d^-1)的奶牛有增加产奶量的趋势,对产奶量低的奶牛没有积极作用,能提高高产奶牛乳蛋白和乳脂肪量。选用9头泌乳中期荷斯坦奶牛,在补饲过瘤胃蛋氨酸和普通蛋氨酸前后连续采血44h,探索蛋氨酸的吸收变化曲线,发现奶牛补饲过瘤胃蛋氨酸后12~16h达到吸收高峰,过瘤胃蛋氨酸能显著提高奶牛血清蛋氨酸水平,而补饲普通蛋氨酸则无明显影响。补饲过瘤胃蛋氨酸和普通蛋氨酸对血清总氨基酸水平均无显著影响。 16 Holstein dairy cows in their midlactation were selected for a 4 × 4 Latin-square design study, to investigate influence of a rumen protected methionine (Met) source at dosage of 0, 8, 12 and 16 g·d^-1, on Met absorption, milk yield, milk protein and fat. The results showed that the supplementation rumen-protected methionine increased milk protein and fat and casein. The supplementation rumen-protected methionine increased milk yield for cows that yielding exceeded 22 kg·d^-1, and no response for cows with lower yields. The quantity of milk protein and fat were improved by rumen-protected methionine in high yielding cows. 9 Holstein dairy cows in their midlactation were taken samples for 44 h before and after supplementing methionine. The result found that the addition of rumen protected methionine led to a sharp increase in the level of serum Met with a peak from 12 to 16 h following the intake. The supplementation rumen-protected methionine increased the level of serum Met, it was significant, while the addition of DL-Met did not achieve such response. The supplementation rumen-protected methionine and DL-Met had no significant effect on serum total amino acids.