日粮中添加杏鲍菇菌糠对湖羊生长性能、瘤胃发酵 和瘤胃发育的影响.

The objective of this study was to investigate the effects of dietary supplementation of Pleurotus eryngii substrate(PES) on the growth performance, rumen fermentation characteristics and rumen development of Hu sheep.[Methods] Forty eight male Hu sheep with good body conditions and similar weight were selected for this experiment, randomly divided into four groups(two-month-old; n=12) and fed with different ratios of PES(0,20%,25%,30%) for 90 days. At the end of the feeding period, body weight, rumen and rumen fluid sample were obtained after slaughter. Volatile fatty acid(VFA),papilla length, papilla thickness and muscular thickness were quantified in the sample using gas chromatography and haematoxylin-eosin(HE),respectively. The expression level of ruminal epithelial cell growth and absorption of VFA related genes were detected by RT-qPCR.[Results] Compared with the control group, dietary supplementation PES did not significantly affect the body weight and dry matter intake(P>0.05). 25% and 30% PES significantly increased the average daily gain(P<0.05). Dietary supplement with PES did not significantly affect the concentrations of acetic acid, total VFA and the ratio of acetic to propionic(P>0.05). There was no significant difference in the pH value of rumen fluid, propionic acid, isovaleric acid and pentanoic acid among the four groups. Dietary supplement with PES significantly increased rumen papilla length(P<0.05). The rumen papilla thickness was significantly higher in the 20% and 25% PES groups than in the control and 30% PES group(P<0.05). There was no significant difference in rumen muscular thickness among the four groups. The relative expressions of insulin growth-like factor binding protein 5 gene(IGFBP-5) and transforming growth factor β1(TGF-β1) mRNA were not significantly different between the groups. Dietary supplement with PES was significantly increased the relative expression of insulin growth-like factor binding protein 6 gene(IGFBP-6) mRNA(P<0.05);compared with the control group and 30% PES group, the relative expression of monocarboxylate transporters 1(MCT-1) mRNA significantly increased in the 20% and 25% PES groups(P<0.05). The mRNA expression level of monocarboxylate transporters 4(MCT-4) was significantly higher in PES group than that in control group(P<0.05). The relative expressions of Na+/K+ ATPase gene(Na+/K+ ATPase) mRNA in the 20% and 25% PES groups were significantly higher than those in the control group and 30% PES group(P<0.05).[Conclusions] Dietary supplementation PES could improve the growth performance, rumen fermentation characteristics and rumen development of Hu sheep. In conclusion,25% PES was the appropriate level of dietary supplementation for Hu sheep. [ABSTRACT FROM AUTHOR]