体外产气法研究棉酚对瘤胃发酵与微生物蛋白产量的影响

Effects of gossypol addition on rumen fermentation and microbial protein yield by in vitro gas production method

为研究棉酚添加浓度对瘤胃产气参数、发酵参数以及瘤胃微生物蛋白合成的影响,本试验采用体外产气法以苜蓿为单一培养饲料进行发酵试验。棉酚的添加浓度依次为0.025、0.05、0.25 mg/kg苜蓿。结果表明:棉酚添加显著抑制了瘤胃产气速率(P<0.05);随着棉酚添加浓度的提高,体外干物质降解率、中性洗涤纤维降解率、酸性洗涤纤维降解率均呈下降趋势,差异显著(P<0.05);棉酚添加浓度的提高导致体外瘤胃挥发性脂肪酸产量下降(P<0.05);棉酚添加使乙酸与丙酸比例显著提高(P<0.05),但不同添加浓度之间差异不显著(P>0.05);0.025 mg/kg添加量对微生物合成效率无显著影响(P>0.05),但随着添加浓度提高,瘤胃微生物蛋白合成效率显著降低(P<0.05)。

In order to study the effects of gossypol concentration on rumen fermentation parameters,gas parameters and rumen microbial protein synthesis （MCP）.In vitro gas production was used to determinate rumen fermentation and mi- crobial protein yield.Results showed that adding gossypol inhibited the rumen gas production rate （P 〈 0.05）.With adding level increasing,in vitro degradation rate of dry matter,neutral detergent fiber,acid detergent fiber showed a significant downward trend（P 〈 0.05 ）.With gossypol concentration increasing ,in vitro rumen volatile fatty acids yield decreased （P 〈 0.05 ）.Gossypol adding affected significantly on the proportion of acetic acid and propionic acid （P 〈 0.05 ）, but no signifi- cant difference was observed among different additive gossypol concentration （P 〉 0.05）.0.025 mg/kg addition of gossypol had no significant effect on the microbial synthesis efficiency （P 〉 0.05）, but with gossypol concentration increasing,rumen microbial protein synthesis efficiency was significantly affected （P 〈 0.05）.