微生物发酵饲料对肉牛生长、 瘤胃发酵和肉品质的影响研究

Effects of microbial fermentation feed on growth performance,rumen fermentation characteristics and meat quality of beef cattle

为研究微生物发酵饲料对肉牛生长性能、瘤胃发酵特性和肉品质的影响,选取平均体重(352.00±12.31)kg西杂牛120头,随机分为5组,每组6个重复,每个重复4只,用微生物发酵饲料以0%、2.5%、5.0%、7.5%、10.0%5个水平进行替代牛日粮中主要蛋白饲料,饲喂90 d,并进行相关指标测定。结果显示:(1)添加微生物发酵饲料对肉牛平均日采食量(ADFI)无显著影响,但在5%水平时日增重(ADG)最高,较对照组升高15.3%(P<0.05)。(2)随微生物发酵饲料添加比例增加,试验组1、2、3、4 pH较对照组分别提高3.3%、6.7%、6.9%、9.5%(P<0.05),挥发性脂肪酸呈下降趋势(P<0.05),氨基氮变化不明显。(3)随着微生物发酵饲料添加量的增加,试验组2、3、4剪切力较对照组分别降低7.8%、1.9%、33.0%(P<0.01),试验组1、2、3、4胆固醇含量较对照组分别降低3.1%、1.9%、4.1%、14.8%(P<0.05)。试验结果表明,以一定比例的微生物发酵饲料替代部分精饲料,可以起到提高生长性能、改善肉品质的作用,但比例过高会降低瘤胃能量代谢,对生长性能产生负面影响。

The objective of the present study was to investigate the effects of a diet containing solid-state microbial fermentation feed(MFF)on the growth performance,rumen fermentation community and meat quality in beef cattle.A total of 120 healthy Simmental crossbred bullocks[(352.00±12.31kg)kg average BW]were blocked by weight and allotted to five treatments with six replicated of four bullocks.The beef cattle in the control group were fed a basal diet,and the beef cattle in other groups were fed the basal diet replaced with MFF at levels of 2.5%,5.0%,7.5%and 10.0%,respectively.The results showed as follows:(1)There was no significant difference in average daily feed intake(ADFI)of beef cattle supplemented with microbial fermented feed,but daily gain(ADG)was the highest at 5%level,which was 15.3%higher than that of control group(P<0.05).(2)The rumen pH in experimental groups increased by 3.3%,6.7%,6.9%and 9.5%(P<0.05)compared with the control group,while the volatile fatty acids in experimental groups decreased(P<0.05),and the changes of amino nitrogen were not significant.(3)Compared with the control group,shear force of experimental groups 2,3 and 4 was decreased by 7.8%,1.9%and 33.0%(P<0.01),and cholesterol content of experimental groups 1,2,3 and 4 was decreased by 3.1%,1.9%,4.1%and 14.8%(P<0.05),respectively,with the increase of microbial fermented feed supplemental level.Results of this study indicated that MFF could be utilized as an alternative protein source and could increase growth performance,optimize intestinal microbial community and improve meat quality.