摘要
本试验旨在通过体外法研究脂多糖(LPS)对瘤胃发酵的影响。选取4头健康、体况相近、安装有永久性瘤胃瘘管的荷斯坦奶牛用于瘤胃液的采集。试验分为对照组(不添加LPS)和试验组(添加LPS 100 000 EU/m L),分别在发酵2、4、8、12、24 h后取样,测定发酵液p H及挥发性脂肪酸、氨态氮、微生物蛋白浓度。结果表明:随着发酵时间的延长,对照组与试验组发酵液p H逐渐下降,发酵液总挥发性脂肪酸、氨态氮、微生物蛋白浓度及乙酸、丙酸、丁酸含量逐渐增加,对照组与试验组之间均无显著差异(P>0.05),但在8、24 h试验组发酵液p H与对照组相比有降低的趋势(0.05≤P<0.10),4、8、24 h试验组氨态氮浓度与对照组相比有降低的趋势(0.05≤P<0.10)。结果显示,在体外发酵条件下,添加LPS具有降低发酵液p H以及氨态氮浓度的趋势,但这一影响并不显著。
This experiment was conducted to examine the effects o f lipopolysaccharide （LPS） on rumen fer-mentation by in vitro method. Four healthy Holstein cows fitted with permanent ruminal cannulas were used as the donor of rumen f luid . Two levels o f LPS [0（control group） and 100 000 E U /m L （experimental group）] were supplemented in substrates of different groups. Samples were collected after being cultured for 2, 4, 8, 12 and 24 h , respectively, to determine pH and concentrations of volatile fatty acids, ammonia nitrogen and microbial protein of fermentation f luid . The results showed as follows： with the extension of fermentation time , fermentation fluid pH in control group and experimental group were gradually decreased, the concentrations of total volatile fatty acids, ammonia nitrogen and microbial protein, and contents o f acetic acid, propionic acid and butyric acid were gradually increased, and compared with control group, experimental group showed no significant changes （P 〉0.05）. Compared with control group, fermentation f luid pH in experimental group showed a downward trend at 8 and 24 h （0.05≤P 〈0.10） , and the concentration o f ammonia nitrogen showeda downward trend at 4, 8 and 24 h （0.05 ≤ P 〈0.10）. The results indicate that the supplementation o f LPS has a tendency to decrease pH and ammonia nitrogen concentration in fermentation f luid under in vitro culture con-ditions, but the difference is not significant.
出处
《动物营养学报》
CAS
CSCD
北大核心
2017年第10期3799-3806,共8页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家"十三五"重点研发课题(2016YFD0700205
2016YFD0700201)
关键词
脂多糖
奶牛
体外发酵
瘤胃发酵
lipopolysaccharide
cow
in vitro fermentation
rumen fermentation
