Effect of different NFC/NDF ratios on ruminal fermentation characteristics and serum biochemical indexes of mutton sheep under corn stover diet mode
The study was to investigate the effects of different NFC/NDF ratios on the ruminal fermentation characteristics and serum biochemical indexes of mutton sheep under a corn straw diet.A total of 15 healthy,50 kg mutton sheep fitted with permanent rumen fistula were seclected,the mutton sheep in the group Ⅰ,group Ⅱ,and group Ⅲ were fed a total mixed diet feeding with NFC/NDF ratios of 0.65,1.02,and 1.57,respectively.The pre-test period was 15 days,and the formal test period was seven days.The results showed that with the increase of NFC/NDF ratio,the rumen pH value decreased.However,the content of ammonia nitrogen(NH3-N)in rumen liquid first increased and then decreased.With the increase of feeding time,bacterial protein(MCP)content first decreased and then increased.With the increase of NFC/NDF ratio,the total volatile fatty acids(TVFA)increased after 6 h.The concentration of serum total protein(TP)in the group Ⅰ was significantly higher than that in other groups(P<0.05),while the concentrations of lipopolysaccharide(LPS)and albumin(ALB)were significantly lower than that in other groups(P<0.05).The concentration of serum triglyceride(TG)in the group Ⅱ was significantly higher than that in the group Ⅰ(P<0.05),and the concentration of free fatty acid(NEFA)was significantly higher than that in other groups(P<0.05).The concentrations of serum urea nitrogen(BUN)and leptin(LEP)in the group Ⅲ were significantly higher than those in other groups(P<0.05),the concentration of insulin-like growth factor-1(IGF-1)was significantly higher than that in the group Ⅱ(P<0.05),and the activity of superoxide dismutase(SOD)was significantly lower than that in other groups(P<0.05).The results showed that when NFC/NDF ratio was 1.02 in the corn straw diet mode,the rumen environment and the antioxidant level of mutton sheep could be improved.