PSXII-1 Effects of early weaning on feed intake, growth performance, and diarrhea rate of Hu lambs

Abstract The objective of this study was to evaluate the effects of early weaning on growth performance, feed intake and diarrhea rate of Hu lambs, and establish the experimental model of early weaning stress in lambs. A total of 60 neonatal male Hu lambs were randomly allotted into 10 pens and 6 lambs in each pen with their ewes. Five pens of lambs were weaned at 21days of age as early weaning group (EW group), and the other 5 pens of lambs were remained with their ewes as control group (CON group). Body weight (BW) were recorded at birth (d0) and at d7, 14, 21, 22, 24, 26, 28, 35,42 and 49 after birth. Solid feed intake of lambs in each pen was recorded and diarrhea incidence was also monitored on daily basis. Data was analyzed using the MIXED model of SAS, and statistical significance was determined at P < 0.05. There was no difference in BW at birth and d21 between the two groups of lambs (P > 0.05). However, BW and average daily gain (ADG) of the lambs in EW group were significantly lower than those in CON group (P < 0.01) since weaning. Solid feed intake of the lambs in EW group were obviously higher than that in CON group (P < 0.01). In addition, the diarrhea rate was significantly higher than that in CON group from d21 to d35 (P < 0.01). The results indicated that lambs weaned at d21 showed strong stress response by significantly decreasing in BW and ADG, and had more feed intake but higher diarrhea rate. Future study is warranted to determine the changes in gut microbiota and barrier function to assess the mechanism of early weaning on health status and growth performance of lambs, and to investigate nutritional intervention methods to alleviate weaning stress.