Effects Of Dietary Diludin On Production Performance, Anti-Oxidized Capacity And Anti-Heat Stress Capacity Of Dairy Cows

This paper studies the effects of dietary diludin on the production, anti-oxidized capacity and anti-heat stress capacity of dairy cows.The result showed diludin could affect the antioxidant enzyme activity, serum metabolins, the level of enzyme and hormone. By this way, they may improve the health condition, feed intake and production performance of dairy cows.28 late lactation stage(203±6 DIM)China Holstein cows on Mei Jiadun dairy farm in Huanggang city were used in this experiment.These cows were randomly divided into two treatment groups by similar parity(3.50±0.21),milk yield(10.84±0.15 kg)and weight(506±8 kg) named as commercial concentrate feed group (S group) and self-made concentrate feed group (Z group), either group was divided into 0.02% diludin group and non-diludin group, the roughage were consistent. The experimental period were 2009.7.20～2009.9.28,10 days for pre-trial period and 60 days for formal experiment period. The average maximum air temperature was 32.82℃of the cowshed, the average minimum air temperature was 24.67℃, the average THI were above 72. The results indicated that:(1) In the formal trial period, adding 0.02% diludine into commercial concentrate feed and self-made concentrate feed could influence the production performance and the milk composition. After 20 days, compared with group S, the milk yield of group Z1 increased 1.73 kg significantly different (P<0.05), at the end of the trial, the milk yield of group Z1 was 2.09 kg higher than the group S(P<0.05). Adding 0.02% diludine into commercial concentrate feed and concentrate feed could incresed the milk fat rate but the milk protein rate was not appeared. At the end of the trial, compared with group S, the milk fat rate of group S1 increased 8.17%(P<0.05), compared with group Z, the milk fat ratio of group Z1 decreased 0.50%(P>0.05). Adding 0.02% diludin into commercial concentrate feed make the milk protein ratio increased by 2.26%.(2) Adding 0.02% diludin into commercial concentrate feed and self-made concentrate feed could increased SOD, GSH-Px, CAT and other antioxidant enzyme activity in the serum, reduced lipid peroxidation MDA content. In all four trial groups, the activity of SOD, GSH-Px, CAT in serum of dairy cows in Z1 group were the highest, lowest concentration of MDA in serum. The results indicated that adding 0.02% diludine into self-made concentrate feed had good effects to improve animal body's antioxidant enzyme activity and eliminate free radicals effectively in heat stressed conditions.(3) Adding 0.02% diludin into commercial concentrate feed and self-made concentrate feed could increased the concentration of total protein, albumin and glucose in serum, decreased the concentration of urea nitrogen in serum; decreased the activity of GOT, GPT and CK in serum; significantly decreased the concentration of cortisol in serum, increased the concentration of T3 and T4 in serum. In all experimental groups, Z1 group has the best status, The results showed that adding 0.02% diludin into self-made concentrate feed could effectivety resist the influence of heat stress on dairy cows serum metabolites, serum enzyme activity and serum hormone.