体外发酵法研究游离棉酚对绵羊瘤胃微生物种群的影响

THE EFFECT OF GOSSYPOL ON RUMEN MICROBIAL POPULATION IN VITRO

本文运用体外发酵法研究了培养底物中不同浓度的棉酚(0.5 mg/g、0.1 mg/g,、0.05mg/g、0 mg/g)对绵羊瘤胃细菌、纤维降解菌、厌氧真菌及瘤胃原虫数量的影响。试验结果表明:体外发酵12h,0.5mg/g棉酚处理组pH值显著高于对照组(P<<0.05),其他时间点各处理组与对照组无显著差异。培养6h时各试验组细菌数量均显著高于对照组(0 mg/g),12h时0.5 mg/g和0.1 mg/g棉酚处理组及24h时的0.05mg/g处理组同样达到显著高于对照组的水平(P<0.05),表明瘤胃细菌对棉酚有较强的耐受性。除6h的0.05mg/g处理组外,其它时间点添加棉酚处理组的纤维降解菌数均显著高于对照组,与瘤胃细菌呈现相似的变化规律。瘤胃真菌则与细菌及纤维降解菌呈相反的变化趋势,3个棉酚处理组真菌数量都低于对照组,0.5 mg/g和0.1 mg/g处理组在24h和48h均显著降低真菌生长(P<<0.01,P<<0.05),说明瘤胃真菌对棉酚较为敏感,低浓度的棉酚就抑制了真菌的生长。与对照组相比添加棉酚在各个时间点上均呈现出显著增加原虫数量的趋势(P<<0.05)。结论:本试验条件下,添加不同浓度的棉酚对绵羊瘤胃总细菌、纤维降解菌、真菌和原虫数量均呈现出显著的影响,总细菌、纤维菌和原虫的影响规律与真菌相反,且在0.1 mg/g和0.5 mg/g添加剂量时更明显。

This experiment was conducted to study the effect of adding different concentration of gossypol to cultivation substrate(0.5 mg/g,0.1 mg/g,0.05 mg/g,0 mg/g) in vitro on the number of rumen bacteria,fiber degrading bacteria,anaerobic fungi and rumen protozoon in sheep.The results showed that the pH of 0.5 mg/g groups were significant higher than the control group at 12h(P<0.05).the number of bacteria in all the treatments was significantly higher than the control group(P<0.05) at 6h.The number of bacteria of 0.5 mg/g and 0.1 mg/g groups at 12h and the group of 0.05mg/g at 24h were also significant higher than those of the control group.The number of fiber degradation bacteria of the treatment groups were significantly higher than those in the control group at each incubation time except for the 0.05 mg/g group at 6h.The change trend of fungi was opposite to those of bacteria and fiber degrading bacteria.The quantity of fungi of the treatment groups were lower than those of the control group.The quantity of fungi of 0.5 mg/g group at 24 h and 0.1 mg/g group at 48 h significantly lower than that of control group(P<0.05).The number of protozoa of treatment groups were significantly higher than that of control group at all incubation time.Conclusion: in this study,the quantity of rumen bacteria,fungi,fiber degrading bacteria and protozoa were significantly influenced by adding different concentration of gossypol.The change trend of bacteria,fiber degrading bacteria and protozoa were opposite to that of fungi.Rumen microbes were more obviously affected by dosage of 0.1 mg/g and 0.5 mg/g.