不同胎次荷斯坦奶牛产奶性能、奶品质和奶氨基酸含量的比较分析

Comparative analysis of milk production performance,milk quality,and milk amino acid content in Holstein cows with different parity

文章旨在研究不同胎次对荷斯坦奶牛产奶性能、奶品质和奶氨基酸含量的影响,试验根据胎次(第1、2、3和4胎次)进行分组,各组分别选择健康和体况良好、免疫接种后的20头奶牛,每组5个重复,每个重复4头。各胎次组奶牛均饲喂相同日粮。结果显示,与1胎次奶牛相比,3和4胎次奶牛DMI分别显著提高16.70%和16.13%(P<0.05);与1胎次相比,2~4胎次奶牛的产奶量分别显著提高5.69%、15.63%和15.41%(P<0.05);与第2胎次相比,第1、3和4胎次奶牛的乳脂率分别显著降低5.33%、5.84%和5.58%(P<0.05);乳蛋白率分别显著降低11.24%、9.80%和10.09%(P<0.05);与1胎次相比,2~4胎次奶牛的4%FCM分别显著提高7.97%、16.88%和16.31%(P<0.05)。与第1、2胎次相比,第3、4胎次牛乳中组氨酸和亮氨酸含量显著降低(P<0.05)、蛋氨酸含量显著提高(P<0.05);与其他胎次相比,第3胎次牛乳中精氨酸含量显著提高(P<0.05);与第1胎次相比,2~4胎次牛乳中异亮氨酸含量显著降低(P<0.05)。与第1和4胎次相比,第2和3胎次牛乳中不饱和脂肪酸含量显著提高(P<0.05);与第1、3和4胎次相比,第2胎次牛乳中多不饱和脂肪酸含量显著提高(P<0.05);与第1、3和4胎次相比,第2胎次牛乳中长链脂肪酸、ω-3脂肪酸、ω-6脂肪酸和总脂肪酸含量显著提高(P<0.05)。结论:随胎次增加,奶牛产奶性能显著提高,但乳品质有所下降,本试验结果表明第2胎次的牛乳质量最佳。

In order to study the effects of different parities on milk performance,milk quality and milk amino acid content of Holstein dairy cows,the experiment was divided according to parities(1st,2nd,3rd and 4th parities),and 20 healthy and well-immunized dairy cows were selected for each group,with 5 replicates as 1 group and 4 cows per replicate.Cows in each parity group were fed the same diet.The results showed that compared with 1st parity cows,the DMI of 3rd and 4th parity cows significantly increased by 16.70%and 16.13%,respectively(P<0.05);Compared with parity 1,the milk production of cows with parity 2-4 significantly increased by 5.69%,15.63%,and 15.41%,respectively(P<0.05);Compared with the second parity,the milk fat percentage of cows in the first,third,and fourth parity decreased significantly by 5.33%,5.84%,and 5.58%,respectively(P<0.05);The milk protein rate significantly decreased by 11.24%,9.80%,and 10.09%,respectively(P<0.05);Compared with 1 parity,the 4%FCM of 2-4 parity cows significantly increased by 7.97%,16.88%,and 16.31%,respectively(P<0.05).Compared with the 1st and 2nd parity,the content of histidine and leucine in milk of the 3rd and 4th parity was significantly reduced(P<0.05),while the content of methionine was significantly increased(P<0.05);Compared with other parity,the arginine content in milk of the third parity was significantly increased(P<0.05);Compared with the first parity,the isoleucine content in milk from 2-4 parity was significantly reduced(P<0.05).Compared with the 1st and 4th parity,the content of unsaturated fatty acids in milk from the 2nd and 3rd parity was significantly increased(P<0.05);Compared with the 1st,3rd,and 4th parity,the content of polyunsaturated fatty acids in the milk of the 2nd parity was significantly increased(P<0.05);Compared to the 1st,3rd,and 4th parity,the long-chain fatty acids in the milk of the 2nd parity areω-3 fatty acidsω-The content of 6 fatty acids and total fatty acids significantly increased(P<0.05).Conclusion:With the increase of parity,the milk production performance of cows significantly improves,but the milk quality decreases.The results of this experiment indicate that the milk quality of the second parity is the best.