高精料日粮对山羊瘤胃和盲肠发酵及生物胺生成与吸收的影响研究

本实验旨在探究饲喂高精料日粮对山羊瘤胃和盲肠发酵、生物胺生成与吸收的影响研究。试验选用6头装有永久性瘤胃瘘管的雄性波杂山羊,随机分成低精料组与高精料组,实验期24 d。结果显示,与低精料组相比,饲喂高精料日粮的山羊瘤胃液中总挥发性脂肪酸、乙酸、丙酸、丁酸、戊酸、总支链脂肪酸、酪胺、腐胺、组胺、甲胺和色胺浓度显著性增加(P<0.05),而瘤胃pH和乙丙比显著降低(P<0.05);饲喂高精料日粮的山羊盲肠内容物中的乙酸、丙酸、总挥发性脂肪酸浓度和上述5种生物胺浓度显著增加(P<0.05);同时,瘤胃和盲肠静脉血中的上述5种生物胺的浓度显著提高(P<0.05)。相关性分析结果表明,瘤胃液中酪胺、腐胺、甲胺和色胺浓度与瘤胃静脉血所对应的生物胺浓度呈显著正相关(P<0.05),且盲肠内容物中酪胺、腐胺、甲胺和色胺与盲肠静脉血中对应的生物胺的浓度呈显著正相关(P<0.05)。结果说明,饲喂高精料日粮促进了山羊瘤胃和盲肠发酵,提高了瘤胃与盲肠内容物中生物胺浓度,暗示高精料日粮可能提高消化道上皮的通透性,促进消化道上皮对生物胺的吸收。

Effects of high concentrate diet on microbial fermentation and biogenic amine formation and absorption in the rumen and cecum of goats

This study was conducted to evaluate the effect of high concentrate diets on ruminal and cecal fermentation and biogenic amines production and absorption in the gastrointestinal tract of goats.Six goats fitted with permanent rumen fistula were randomly divided into low concentrate group and high concentrate groups for an experiment that lasted 24 days.The results showed that,compared with the low concentrate group,high concentrate diets increased the concentrations of total volatile fatty acid,acetate,propionate,butyrate,total branched chain fatty acid,tyramine,putrescine,histamine,methylamine and tryptamine (P＜0.05).Ruminal pH and the ratio of acetate to propionate decreased (P＜0.05).A high concentrate diet also improved the levels of acetate,propionate,total volatile fatty acid and the five biogenic amines in cecal digesta (P＜0.05).Compared with the control group,the concentrations of biogenie amines contents were higher in the high concentrate group in rumen and cecal vein blood (P＜0.05).Correlation analysis revealed that the biogenic amines contents of tyramine,putrescine,methylamine and tryptamine in rumen fluid and rumen vein blood were significantly positively correlated (P＜0.05).In addition,significant correlations of the five amines contents were observed between cecal digesta and cecal vein blood (P＜0.05).These results show that high concentrate diets significantly affect ruminal and cecal fermentation,indicating that high concentrate feeding might increase ruminal and cecal epithelial permeability and thus stimulate the absorption of biogenic amines from rumen and cecum.