不同处理方式的苜蓿草对犊牛生长性能、瘤胃发酵及微生物蛋白合成的影响

Effects of different treatments of alfalfa on growth performance,rumen fermentation and microbial protein synthesis of calves

文章旨在评估苜蓿草的不同处理方式及饲料形式对犊牛生长性能、瘤胃发酵及微生物蛋白合成的影响。试验将60头均重为40.01kg的刚出生犊牛随机分为4组,每组5个重复,每个重复3头牛。试验日粮采用多因素方差设计,2种苜蓿草处理方式(切碎和制粒)和2种饲料形式(粉料和颗粒料)。T1组为切碎苜蓿草+粉料,T2组为制粒苜蓿草+粉料,T3组为切碎苜蓿草+颗粒料,T4组为制粒苜蓿草+颗粒料。结果:无论苜蓿草处理方式如何,颗粒饲料组犊牛70d体重、1~50d和1~70d平均日采食量和日增重均显著高于粉料组(P<0.05)。粉料全混合日粮较颗粒料组犊牛瘤胃氨氮浓度显著提高(P<0.05)。T3组犊牛尿囊素和嘌呤衍生物排泄量显著高于其他组(P<0.05),但无论苜蓿草处理方式如何,粉料组犊牛的尿素氮排泄量显著高于颗粒料组(P<0.05),但微生物蛋白合成量显著低于颗粒料组(P<0.05)。结论:无论苜蓿草的处理方式如何,颗粒全混合日粮均可改善犊牛的生长性能,降低尿氮排出,提高了氮效率和微生物蛋白合成量。

The objective of this study was to evaluate the effects of alfalfa grass treatment and feed form on growth performance,rumen fermentation and microbial protein synthesis of calves.Sixty newborn calves with an average body weight of 40.01 kg were randomly divided into 4 groups with 5 replicates per group and 3 calves per replicate.The experimental diet was designed with multivariate variance,two alfalfa treatments(chopped and granulated)and two feed forms(powder and granulated).Group T1 was composed of chopped alfalfa grass+powder,group T2 was composed of granulated alfalfa grass+powder,group T3 was composed of chopped alfalfa grass+granular,and group T4 was composed of granulated alfalfa grass+granular.Results:Regardless of alfalfa grass treatment,the body weight at 70 d,average daily feed intake and daily gain at 1~50 d and 1~70 d in pellet diet group were significantly higher than those in powder diet group(P<0.05).The rumen ammonia nitrogen concentration of calves in total mixed diet with powder was significantly higher than that in granular diet group(P<0.05).The excretion of allantoin and purine derivatives of calves in T3 group was significantly higher than that in other groups(P<0.05),and regardless of alfalfa grass treatment,the excretion of urea nitrogen in powder group was significantly higher than that in pellet group(P<0.05),but the microbial protein synthesis was significantly lower than that in pellet group(P<0.05).Conclusion:No matter how alfalfa grass is treated,pellet mixed diet can improve the growth performance,reduce urinary nitrogen excretion,increase nitrogen efficiency and microbial protein synthesis of calves.