饲粮精粗比对贵乾半细毛羊生长性能、血清生化指标、瘤胃发酵参数及经济效益的影响OA

The experiment aimed to investigate the effects of dietary concentrate-to-roughage ratio on the growth performance,serum biochemical parameters,rumen fermentation parameters,and economic benefits of Guiqian semi-fine wool sheep in Northwest Guizhou.A total of 60 healthy male lambs with body weight of(20.29±1.58)kg were randomly divided into five groups,with three replicates per group and four lambs per replicate.Groups Ⅰ to Ⅴ were fed diets with concentrate-to-roughage ratios of 20∶80,30∶70,40∶60,50∶50,and 60∶40,respectively.The pre-test period was seven days,and the formal test period was 75 days.The results showed that group Ⅲ had the highest average daily gain,which was significantly higher than that in groups Ⅰ and Ⅴ(P<0.05).Group Ⅰ had the highest average daily feed intake,which was significantly higher than that in group Ⅴ(P<0.05).Group Ⅲ had the lowest feed-to-gain ratio,which was significantly lower than that in groups Ⅰ and Ⅴ(P<0.05).The content of serum urea nitrogen(BUN)in group Ⅲ was significantly higher than that in groups Ⅰ and Ⅱ(P<0.05).Rumen fluid propionic acid content in groups Ⅰ,Ⅱ,and Ⅲwas significantly lower than that in groups Ⅳ and Ⅴ(P<0.05),while the acetate/propionate was significantly higher than that in groups Ⅳ and Ⅴ(P<0.05).The rumen fluid ammonia nitrogen content in group Ⅲ was significantly higher than that in group Ⅰ(P<0.05).Group Ⅲ achieved the highest economic benefit,with net income increased by 18.77%,13.84%,21.85%,and 133.33%compared with groups Ⅰ,Ⅱ,Ⅳ,and Ⅴ,respectively.The study shows that an appropriate dietary concentrate-to-roughage ratio can effectively improve the growth performance and enhance economic benefits of Guiqian semi-fine wool sheep.Considering all indicators comprehensively,the diet with a concentrate-to-roughage ratio of 40∶60 yields the optimal effect.