热应激对荷斯坦牛与荷-娟F1牛抗氧化能力的影响

Effect of heat stress on Anti-Oxidative Capability in Holstein and Jersey dairy cows

临床健康的荷斯坦乳牛和荷斯坦牛-娟姗牛杂交F1牛(荷-娟F1)各20头,分为2组,分别于冬季12月份(牛舍日平均气温为10.35℃,THI为47.24)和次年夏季7月份(牛舍日平均气温为38.07℃,THI为82.61)条件下,研究热应激对血清中丙二醛(MDA)含量,总超氧化物歧化酶(T-SOD)活力,总抗氧化能力(T-AOC)的影响。结果表明:热应激期间荷-娟F1血清中MDA含量显著低于荷斯坦牛(P<0.05);T-SOD活力显著高于荷斯坦牛(P<0.05);T-AOC有升高的趋势但差异不显著(P>0.05)。在非热应激期间,荷-娟F1与荷斯坦牛相比血清中的MDA含量、T-SOD活力和T-AOC均无显著差异(P>0.05)。荷-娟F1和荷斯坦牛在热应激期间的血清中MDA含量、T-SOD活力与非热应激期差异均极显著(P<0.01),荷斯坦牛血清中T-AOC差异显著(P<0.05),而荷-娟F1血清中T-AOC差异不显著(P>0.05)。由此表明,热应激对乳牛的抗氧化能力产生显著的影响;热应激期间荷-娟F1的抗氧化能力高于荷斯坦牛,更能适应热带和亚热带地区高温高湿的气候条件。

The effects of heat stress on changes in the MDA contents,T-SOD and T-AOC activities were evaluated in two groups of 40 healthy Holstein and Jersey×Holstein dairy cows. These animals were subjected to a cool environment when the mean temperature-humidity index (THI) was 47.24 and temperature was 10.35℃ during the month of December. This experiment was repeated during the hotter month of July of the following year,when the mean THI was 82.61 and temperature was 31.07℃. The results were showed as follows: Dur...