Effect of weaning time on growth performance and rumen development of Hu lambs

This experiment was determined the effect of weaning time on growth performance, rumen fermentation, and microbial bacterial community of lambs. Forty eight Hu lambs were randomly divided into 4 treatments. Control lambs were ewe reared (ER), while others were weaned at d 10, 20, or 30 after birth (EW10, EW20 and EW30) and fed milk replacer artificially until d 60. All lambs had ad libitum access to same creep feed from d 15 to 90. Results showed that average daily gain, creep feed intake, final body weight, hot carcass and rumen weight of EW10, EW20 and EW30 were greater (P < 0.05) than ER. The ammonia N concentration of EW20 and EW30 was greater (P < 0.05) than EW10 and ER. Butyric acid in EW10 and EW20 was greater (P < 0.05) than EW30 and ER. The richness and biodiversity of bacterial communities had no difference (P > 0.05). The predominated rumen bacterial composition in phyla level had no difference, but the minor phyla present, Proteobacteria, had difference. These results demonstrated that weaning time could improve the growth performance and rumen weight and slightly affect rumen fermentation. Weaning at d 10 was recommended to fanner to maintain prior rumen development and performance in lambs.