Effect of different NFC/NDF ratios on ruminai 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 H, and group M 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 H 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 M 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 H (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. [ABSTRACT FROM AUTHOR]