围产期不同水平阴阳离子差日粮对奶牛生产性能的影响

The Study on Lactation Performance of Periparturient Cows Fed Diets with Varying Cation-anion Difference

试验旨在研究不同水平阴阳离子差(DCAD)日粮对江西红壤地区围产期奶牛泌乳性能的影响。将12头荷斯坦经产干奶牛按照随机区组设计分为3组:对照组、试验1组和试验2组,其日粮DCAD水平分别为+103.27m Eq/kg DM、-109.61m Eq/kg DM和-157.83m Eq/kg DM。结果表明:围产期奶牛日粮干物质采食量、日泌乳量、乳成分(乳蛋白率、乳脂率与乳糖率)未受到DCAD水平影响(P>0.05);尿液p H、乳中体细胞数随DCAD水平的降低而降低,两个试验组均显著低于对照组(P<0.05),但两试验组间的差异不显著(P>0.05)。结果提示:在江西红壤地区养殖奶牛,可以给围产期奶牛添加阴离子盐以降低日粮阴阳离子差水平,不仅不会影响产后泌乳性能,而且还能降低乳中体细胞数,提高牛奶品质。在本研究条件下,奶牛围产期日粮阴阳离子差水平以-110^-150mEq/kg DM为宜。

The objective of this study was to evaluate the lactation performance of periparturient cows fed diets with varying cation-anion difference（DCAD） in Jiangxi Red Soil Regions（JRSR）. Totally 12 Holstein multiparous cows were randomly assigned to 3 blocks of 4 cows and were fed 1 of 3 diets with DCAD at ＋103.27 m Eq/kg,-109.61 m Eq/kg DM and-157.83 m Eq/kg DM for control, treatment 1 and treatment 2, respectively. The results showed that feeding of lower DCAD did not alter dry matter intake（DMI）, milk yield, milk composition（Milk protein, fat and lactose） of 3 DCAD treatments（P0.05）, but reduce the urine p H and milk somatic cell count（P0.05）compared with control. However, the difference of urine p H and milk somatic cell count between treatment 1 and treatment 2 was not significant（P0.05）. It is suggested that anionic salts supplementation（-110^-150 m Eq/kg DM） in the dry-off diet for cows in JRSR is appropriate which may lead to reduce milk somatic cell count with non-significant impact on DMI and lactation performance.