The objective of present study was to investigate the effect of dietary wine grape pomace (WGP) supplementation on metabolism and development of rumen in lambs.A total of 24 Dorper (♂)× Small Tail Han sheep (♀) F1 male lambs ((25±1) kg of body weight,5 month old)were randomly selected and divided into 4 groups equally.Lambs in 4 groups were fed with diets supplemented with WGP at 0％,5％,10％,20％ on a dry weight basis (group 0％,group 5％,group 10％,group 20％),respectively.The experiment lasted for 80 d.At the end of experiment,all lambs were slaughtered,and stomaches were weighted.The rumen fluid was collected for analyzing rumen fermentation and enzymes activity of microorganism,and rumen tissues were sampled for epithelial development measurements.The results showed that:1) No significant effect of dietary WGP supplementation on rumen pH and total volatile fatty acid (TVFA) concentration was observed (P＞0.05).Propionic acid molar ratio was significantly increased,whereas acetic acid molar ratio and acetic acid/propionic acid ratio were decreased when lambs were fed with WGP diet (P＜0.05);meanwhile,decreased concentrations of lactic acid,ammonia nitrogen and urea nitrogen were observed (P＜0.05).2) Amylase,protease and cellulases activity (except for pectase) were decreased with the increasing WGP supplementation levels (P＜0.05),while pectase activity was exhibited as group 10％＞0％＞5％＞20％ (P＜0.05),the total protein concentration in rumen fluid had no significant difference among different groups (P ＞ 0.05).3)Among factors related to VFA absorption and metabolism,relative mRNA expression of MCT1 and AE2 were significantly decreased when lambs were fed with WGP diet (P＜0.05),whereas no significant difference at MCT4 and Na+-K+-ATPase mRNA expression levels among different groups were observed (P＞0.05).4) Both absolute weight and relative weight of rumen were not significantly altered among the groups (P＞0.05).The cuticle thickness of lambs in WGP-added groups was significantly higher than that in group 0 ％ WGP,and ruminal papillae length in group 20％ WGP was significantly lower than that in other groups (P＜0.05).In conclusion,WGP could effectively change rumen metabolism,and benefit to rumen development.Moreover,WGP supplementation amount could not exceed 10％ considering the rumen epithelial tissue development.%旨在研究日粮中添加酿酒葡萄皮渣(WGP)对绵羊瘤胃代谢及发育的影响.试验随机选取24只杜泊×小尾寒羊杂交一代公羔((25±1) kg,5月龄),采用单因素完全随机设计平均分为4组,分别饲喂不同WGP添加水平日粮(0％,5％,10％,20％),试验期80 d.试验结束后,屠宰并取样,分别称量各胃室重量;采集瘤胃液及瘤胃组织,研究瘤胃发酵参数、微生物酶活性及瘤胃上皮组织发育情况.结果表明:1)日粮添加WGP对绵羊瘤胃液pH及总挥发性脂肪酸(TVFA)浓度影响不显著(P＞0.05),但显著提高丙酸摩尔比,降低乙酸摩尔比、乙丙比及乳酸、氨态氮、尿素氮浓度(P＜0.05).2)淀粉酶、蛋白酶及各纤维素酶(除果胶酶)活性均随WGP添加水平升高而显著下降(P＜0.05),果胶酶活性表现为10％组＞0％组＞5％组＞20％组(P＜0.05),瘤胃液总蛋白浓度在各处理间无显著差异(P＞0.05).3) VFA吸收与代谢相关的因子中,MCT1和AE2 mRNA相对表达量随WGP添加而显著下降(P＜0.05),而MCT4与Na+ K+-ATPase在各处理之间无显著差异(P＞0.05).4)日粮添加WGP对瘤胃绝对重量及相对重量均无显著影响(P＞0.05).此外,WGP的添加可显著降低角质层厚度,20％添加组瘤胃乳头长度显著低于其他组(P＜0.05).综上,绵羊日粮中添加WGP可在一定范围内改变瘤胃代谢,有利于瘤胃发育.从瘤胃上皮组织发育来看,WGP添加量不宜超过10％.
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