有机铬对肉牛生长性能、血液生化指标及肌肉脂肪酸组成的影响

Effects of supplementation of organic chromium on growth performance,blood biochemical indices and muscle fatty acid of beef cattle

文章旨在评估日粮添加有机铬对肉牛生长性能、肌肉脂肪酸组成及血液生化指标的影响。试验选择平均初始体重为(599.85±1.80)kg的荷斯坦肉牛24头,随机分为2组,每组12头,每组中的2头牛为一个重复。对照组饲喂以玉米、青贮玉米为主的日粮,处理组饲喂营养水平一致的日粮+0.15mg/kg蛋氨酸铬。在为期20周的饲养试验后分析生长性能及肌肉化学成分。结果:与对照组相比,有机铬组肉牛的日增重显著提高6.87%(P<0.05),料重比显著降低7.43%(P<0.05)。有机铬组肌肉粗灰分和胆固醇含量较对照组分别显著降低9.78%和22.06%(P<0.05)。日粮添加有机铬对大部分肌肉脂肪酸占比均无显著影响(P>0.05),但有机铬组肌肉多不饱和脂肪酸浓度较对照组显著提高49.21%(P<0.05)。有机铬组血清丙二醛、胆固醇和低密度脂蛋白浓度较对照组分别显著降低51.03%、23.78%和39.22%(P<0.05),但与对照组相比,有机铬组血清高密度脂蛋白浓度显著提高53.33%(P<0.05)。结论:在本研究条件下,肉牛生长后期日粮添加0.15mg/kg蛋氨酸铬可以提高日增重和饲料效率,改善血液代谢产物,提高肌肉中多不饱和脂肪酸含量。

This experiment was conducted to evaluate the effects of dietary organic chromium supplementation on growth performance,muscle fatty acid composition and blood biochemical indices of beef cattle.Twenty-four Holstein beef cattle with an average initial body weight of 599.85±1.80 kg were randomly divided into 2 groups with 6 replicates per group and 2 cows per replicate.The control group was fed with corn and silage corn as the main diet,and the treatment group was fed with the diet with similar nutrient level as the control group,but the diet was supplemented with 0.15 mg/kg chromium methionine.Growth performance data and muscle chemical composition were analyzed after a 20-week feeding trial.Results:Compared with the control group,the daily gain of beef cattle in organic chromium group was significantly increased by 6.87%(P<0.05),and the ratio of feed to gain was significantly decreased by 7.43%(P<0.05).Compared with the control group,the contents of muscle ash and cholesterol in organic chromium group were significantly decreased by 9.78%and 22.06%(P<0.05),respectively.Organic chromium supplementation had no significant effect on the proportion of most fatty acids(P<0.05),but the concentration of polyunsaturated fatty acids in muscle of organic chromium group was significantly increased by 49.21%(P<0.05)compared with that of control group.Compared with the control group,the serum concentrations of malondialdehyde,cholesterol and low-density lipoprotein in organic chromium group were significantly decreased by 51.03%,23.78%and 39.22%(P<0.05),respectively,but the serum high-density lipoprotein concentration in organic chromium group was significantly increased by 53.33%(P<0.05).Conclusions:Under the condition of this study,adding 0.15 mg/kg chromium methionine in the late growth period of beef cattle can increase daily gain and feed efficiency,and improve blood metabolites and polyunsaturated fatty acid composition of beef.