Effect Of Undernutrition And Compensation On The Visceral Organs And The Blood CD4~+,CD8~+T Lymphocytes In Lambs

This experiment was conducted to study the effects of different dietary energy and protein ratio restriction and feed compensation on the growth of visceral organs, small intestinal mucosa structure and CD4+,CD8+ T lymphocytes in peripheral blood in lamb. Eighty WuZhuMuQin lamb (average body weight 14.72 kg) were selected and divided into 4 groups. The feeding trial lasted 150 days includes 60d of feed restriction and 90d of feed compensation. The nutrition level of the diet in feed restriction period (0-60d) were ME:10.88MJ/kg,CP:10% for restricted groupâ… (RGâ… ); ME:9.41MJ/kg, CP: 10% for restricted groupâ…¡(RGâ…¡); and ME: 8.62MJ/kg, CP:5.7% for restricted groupâ…¢(RGâ…¢) and ME:10.88MJ/kg, CP: 15% for control group (CG). Experimental diets were ad libitum and water were available during the entire experimental period. All lamb were offered the same diet (ME:9.75 MJ/kg;CP:12%) during nutrition compensatory period (60-150days).The experimental results were showed as follow:(1) The body weight of feed restricted lamb all show certain compensatory potency. The protein restriction have more negative effect on compensatory growth. Lamb fed low protein and energy diet (RGâ…¢) showed the least compensatory growth.(2) Feed restriction inhibited the growth of the visceral organs and with the increasing of feed restriction degree the inhibitory effect was increased.During the repletion phase, all visceral organs show compensatory growth.(3) The development and structure of small intestine of lamb is closely related to diet composition.Different nutrition restriction levels limit the development of the intestinal mucosa structure at different degrees and led to vary recovery efficiency.(4) Different protein and energy restriction have different inhibitory effect on development of thymus and spleen of lamb which induced varied immunity. During the repletion phase, the immune organ show compensatory growth and CD4+, CD8+ T lymphocytes in the blood show correspondent change which indicated the increasing of the immunity of feed restriction lamb.