Effect Of Nutrient Restriction And Compensation On Growth, Adipose Tissue Constitution And Blood Index In Mongolian Lamb

This study was conducted to investigate effects of nutrient restriction and different compensation on growth, ruminal environment, blood index, adipose development and composition changes in Mongolian lamb. Thirty male lambs (average 20.70±3.51 kg body weight) were allotted into control and feed restricted group, each group included 15 lambs. The experiment was lasted for 120 d with 0d-60d of feed restriction and 60d-120d of feed compensation. During restriction period, control animal was ad libtum feeding of diet with concentrate to forage ratio of 3:7. Restricted group was fed limited amount of hay. At the end of restriction period, five lambs were selected from each group and slaughtered. During nutrient compensation period, the remaining lamb in each group were divided into hey group (CH and CM), or maize straw group (RH and RM). H represented for animals feeding with the concentrate to forage ratio of 5:5 diet, M represented for animal feeding with the concentrate to forage ratio of 7:3 diet. In this experiment period, all animal was fed ad libtum. The experiment results were showed as follow:(1) Nutrient restriction significantly (P<0.05) influenced body weight and ruminal environment in lamb. After nutrient compensation, the lamb weight and ruminal environment were recovered. Different forage to concentrate ratio diet significantly influenced lamb ruminal homeostasis and body weight. The lamb weight in RM group was significantly lower (P<0.05) as compared to CH group. And maize straw group significantly influenced the rumen environment.(2) Feed restriction induced significant decreases in serum concentration of BUN (P <0.05) and significant increases the concentration of creatinine (P<0.05) on 30 d and 60 d. Feed restriction significant increased the concentration of MD A (P< 0.05) on 30 d, and significant decreased the concentration of H2O2 (P<0.05) on 60 d. After nutrient compensation, the blood index was recovered to control group level. Maize straw group showed significantly increased (P<0.05) in the concentration of creatinine on 90 d and 120 d, and significantly increased the concentration of BUN on 120 d.(3) Nutrient restriction significantly (P<0.05) influenced cell amount and fatty acids composition in different adipose tissue of the lamb. All adipose cell growth and development was restricted. After nutrient compensation, adipose cell hypertrophy and hyperplasia in subcutaneous fat were recovered to the control group level, but omental fat cell hyperplasia was not recovered to the control group level. After nutrient compensation, the fatty acid composition was not significant changed. The maize straw group adipose cell number was significant higher as compared to those of hay group (P <0.05).