日粮阴阳离子平衡对泌乳中后期热应激奶牛血液生化指标的影响

Effects of dietary anion cation balance on blood biochemical parameters of mid-late lactation heat stressed dairy cows

试验旨在研究日粮阴阳离子平衡对泌乳中后期热应激奶牛血液生化指标的影响,选取试验奶牛32头分为4组,每组8头,日粮DCAB分别为对照组83mEq/kgDM、试验Ⅰ组172mEq/kgDM、试验Ⅱ组217mEq/kgDM、试验Ⅲ组357mEq/kgDM。研究结果表明:DCAB增加可在一定程度上提高奶牛血液的缓冲能力,缓解奶牛热应激,随DCAB增加,血液的pH值及HCO3-浓度升高,CO2分压下降,差异均不显著(P>0.05);高的DCAB能增加血液Na+、K+浓度,K+显著增加,Cl-显著下降(P<0.05);高水平的DCAB日粮,能使泌乳中后期血液ALP含量增加,CK、ALT含量减少,差异不显著(P>0.05)。综合DCAB对血液缓冲能力、血液生化指标等方面考虑,在泌乳中后期DCAB为217mEq/kgDM时饲喂效果较好。

The experiment was conducted to study the effects of DCAB on blood biochemical pa- rameters of mid-late lactation heat stressed dairy cows. 32 cows were selected respectively, and were randomly assigned into 4 groups, and four levels of DCAB were as follows： control group was 83 mEq/kgDM, group Ⅰ was 172 mEq/kgDM, group Ⅱ was 217 mEq/kgDM, groupⅢ was 357 mEq/kgDM diet. The results showed as follows： abilities of blood buffer of dairy cows were increased with DCAB increasing, blood pH and HCO3- concentration increased,CO2 partial pres- sure decreased, but there were no significant differences（P〉0.05）; high DCAB can increase the blood Na＋, K＋ concentration, K＋ was significantly increased, Cl- was significantly decreased（P〈 0.05）; a high level of DCAB diet could increase blood ALP content, decrease CK,ALT levels, the differences were not significant（P〉0.05）. Considering of the results above, a better effect of dairy cows was observed in group Ⅱ with DCAB of 217 mEq/kgDM.