拉沙里菌素对肉牛日粮养分消化代谢和甲烷排放的影响

Effects of Lasalocid on Digestion and Metabolism of Dietary Nutrients and Methane Emission in Simmental Beef Cattle

本试验旨在评价拉沙里菌素对西门塔尔牛日粮养分消化代谢和甲烷排放的影响。选取12月龄左右、体况良好、体重近似的西门塔尔牛48头,随机分为4组。对照组饲喂基础日粮(混合精料+玉米秸秆;精粗比45∶55);处理组分别在基础日粮中添加100、200、300 mg/d拉沙里菌素。饲养试验结束后每组随机抽取3头牛进行消化代谢试验。结果表明:日粮添加拉沙里菌素200 mg/d和300 mg/d时,干物质采食量、平均日增重、日粮粗蛋白表观消化率、采食氮、可消化氮、沉积氮、瘤胃内丙酸和尿嘌呤衍生物含量均显著高于对照组(P<0.05)。200 mg/d组和300 mg/d组饲料转化效率、瘤胃内乙酸含量、氨态氮浓度以及甲烷产量、粪氮和尿氮含量显著低于对照组(P<0.05)。试验表明,日粮添加拉沙里菌素能改善瘤胃发酵和氮的利用,从而提高生产性能和减少甲烷排放,其适宜添加量为200 mg/d。

The objective of this study was to evaluate the effects of lasalocid on digestion and metabolism of dietary nutrients, and methane emission in Simmental beef cattle. Forty-eight 12-months-old Simmental beef cattles with good body condition and similar body weight were randomly divided into four groups. The control group was fed basic diet （concentrate and corn stover; concentrate ： roughage 45：55）; The supplementation of lasalocid with 100, 200 and 300 mg per cattle per day was added randomly to determine digestibilities and to the basic diet, respectively. Three cattles in each group were selected metabolism of dietary nutrients after feeding experiments. The results showedthat dry matter intake, average daily gain, crude protein apparent digestibility, intake nitrogen, digestible nitrogen, retenion nitrogen, propionate and purine derivatives in groups supplemented lasalocid at 200 mg/d and 300 mg/d were higher than that of in control group （P〈0.05）. Feed conversion rate, acetate, ammonia N, methane emission, feces nitrogen and urine nitrogen in groups supplemented lasalocid at 200 mg/d and 300 mg/d were lower than that of control group （P〈 0.05）. The study showed that the addition of lasalocid in beef cattle diet could improve rumen fermentation, nitrogen utilization and production performance, decrease methane emission, the optimal dose of lasalocid was 200 mg/d.