饲粮蛋白质水平对广丰山羊肉品质、血清酶活性、瘤胃发酵和肠道发育的影响

Effects of Dietary Protein Level on Meat Quality,Serum Enzyme Activity and Intestinal Develpment of Guangfeng Goats

本试验旨在研究饲粮蛋白质水平对广丰山羊肉品质、血清酶活性、瘤胃发酵和肠道发育的影响。选择体重相近、健康的广丰山羊30只,随机分为3组,分别饲喂高(H组)、中(M组)和低蛋白质水平(L组)的精料,粗料为芒草鲜草,每组10只(公母各占1/2)。预试期14 d,正试期70 d。结果表明:1)H组的山羊肌肉pH 45 min显著高于L组(P<0.05),而熟肉率则显著低于L组(P<0.05),其他指标各组间无显著差异(P>0.05)。2)M组血清谷草转氨酶、谷丙转氨酶和碱性磷酸酶活性均低于其他2组,但各组间差异不显著(P>0.05)。3)L组瘤胃乙酸、丙酸和总挥发性脂肪酸的含量显著高于H组(P<0.05),其他指标各组间无显著差异(P>0.05)。M组瘤胃黄色瘤胃球菌、栖瘤胃普雷沃菌、嗜淀粉瘤胃杆菌和白色瘤胃球菌基因相对表达量显著高于其他2组(P<0.05),H组瘤胃的溶纤维丁酸弧菌和产琥珀酸丝状杆菌基因相对表达量显著高于其他2组(P<0.01)。4)L组回肠的绒毛高度以及空肠绒毛高度、绒毛高度/隐窝深度(VH/CD)显著或极显著高于H组(P<0.05或P<0.01),其他指标各组间无显著差异(P>0.05)。综上所述,饲粮蛋白质水平能够影响广丰山羊肉品质、瘤胃发酵和肠道发育。从本试验结果来看,降低饲粮蛋白质水平能够改善山羊肉品质,提高瘤胃发酵和小肠吸收功能。

To study the effects of dietary protein level on meat quality,serum enzyme activity and intestine development of Guangfeng goats,thirty healthy goats with similar body weight were chosen and randomly divided into three groups with ten sheep per group(half of male and female).Goats in each group were fed concentrates with high(group H),medium(group M)and low protein levels(group L),respectively.The roughage was fresh grass of Miscanthus in all groups.The experimental period contained a 14-day pre-experiment and a 70-day experiment.The results showed as follows:1)the pH of goat muscle of group H was significantly higher than that of group L(P<0.05),while cooked meat percentage of group H was significantly lower than that of group L(P<0.05).There was no significant difference in other indexes between groups(P>0.05).2)The activities of alanine aminotransferase,alanine aminotransferase and alkaline phosphatase of group M were lower than those of other two group,while there was no significant difference among groups(P>0.05).3)The contents of acetic acid,propionic acid and total volatile fatty acids of group L were significantly higher than those of group H(P<0.05),but the other indexes were no significant difference between groups(P>0.05).The relative expression levels of Ruminococcus flavefaciens,Prevotella ruminicola,Ruminobacter amylophilus,Ruminococcus albus of group M were significantly higher than those of other two groups(P<0.05 or P<0.01).The relative expression levels of Butyrivibrio fibrisolvens and Fibrobacter succinogenes of group H were significantly higher than those of other two groups(P<0.01).4)The villus height of ileum and the villus height and villus height/crypt depth(VH/CD)of jejunum of group L were significantly higher than those of group H(P<0.05 or P<0.01),but the other indexes were no significant difference between groups(P>0.05).In conclusion,dietary protein level can affect meat quality,rumen fermentation and intestinal function of Guangfeng goat.Reducing dietary protein level can improve meat quality,improve rumen fermentation and intestinal absorption in this experiment.