Effects of Adding Cellulase to Starter Diets on Growth Performance,Rumen Fermentation and Serum Biochemical Indices of Lambs
This experiment was conducted to investigate the effects of adding cellulase to starter diets on growth performance,nutrient digestibility,rumen fermentation and serum biochemical indices of lambs before and af-ter weaning.Twenty-four male Hu sheep of 10-day-old with similar birth weight were randomly divided into 2 groups with 12 lambs in each group.Lambs in the control group were fed the starter diet without cellulase,and those in experimental group were fed the starter diet supplemented with 0.1%cellulase.The experiment lasted for 111 days.Lambs were fed and suckled with ewe from 1 to 9 days of age,separated from ewe at 10 days of age,raised in a single pen,and started to feed milk replacer powder and starter diet,then stopped feeding milk replacer powder at 61 days of age.The results showed as follows:1)before and after weaning,adding cellu-lase to starter diets significantly decreased the average daily feed intake(ADFI)of lambs(P<0.05);before weaning,compared with the control group,the average daily gain(ADG)of lambs in experimental group was significantly increased(P<0.05),and the ratio of feed to gain(F/G)was significantly decreased(P<0.05);after weaning,ADG in experimental group was significantly decreased compared with the control group(P<0.05).2)Adding cellulase to starter diets significantly increased the digestibilities of neutral detergent fiber(NDF)and acid detergent fiber(ADF)of lambs before weaning(P<0.05),and significantly increased the digestibility of dry matter(DM)and organic matter(OM)after weaning(P<0.05).3)Before and after weaning,adding cellulase to starter diets significantly decreased the rumen contents of ammonia nitrogen and isovaleric acid of lambs(P<0.05);before weaning,compared with the control group,the rumen contents of total volatile fatty acids,acetic acid,propionic acid and butyric acid of lambs in experimental group were sig-nificantly increased(P<0.05),and the rumen pH was significantly decreased(P<0.05);after weaning,compared with the control group,the rumen contents of total volatile fatty acids,acetic acid,propionic acid,isobutyric acid and valerate acid in experimental group were significantly decreased(P<0.05).4)Before wea-ning,adding cellulase to starter diets significantly increased the contents of total protein(TP),albumin(ALB)and glucose(GLU)and the alanine aminotransferase(ALT)activity of in serum of lambs(P<0.05),and significantly decreased the contents of globulin(GLB)and urea(UREA)in serum(P<0.05);after weaning,adding cellulase to starter diets significantly increased the contents of GLB and total cholesterol(TC)in serum(P<0.05),and significantly decreased the contents of ALB,UREA and GLU in serum(P<0.05).In conclusion,adding cellulase to starter diets can improve the digestibilities of dietary nutrients before and after weaning,improve the rumen fermentation before weaning and improve growth performance of lambs before weaning.[Chinese Journal of Animal Nutrition,2024,36(5):3170-3182]
lambscellulasegrowth performancenutrient digestibilityrumen fermentationserum bio-chemical indices