Effects Of Different Cysteamine Levels On Production Performance And Degradation Rate Of Nutrient Substance In Crossbred Sheep

24 healthy crossbred sheeps that were borned by germany merino♂×northeast fuzz sheep♀and whose body weights closed to each other were choosed to study the effect of cysteamine(cs) on the growth performance,biochemical indicator of blood,performance of abatage and quality of carcass of the crossbred sheeps,in this experiment first part.12 crossbred rams that were borned by germany merino♂×northeast fuzz sheep♀and that were installed nonvolatil gastric fistula were choosed to study the effect of cs on degradation ratio of nutrient substance of the crossbred sheep,in this experiment second part.The experiments above were adopted experimental design of completely randomization and divided 4 groups,one control group and 3 experimental groups.The feed of 3 experimental groups was seperately added 10,15,20mg/kg·BW cs on the basis of the feed of control group.The finding showed: (1) Added 10mg/kg·BW CS in feed,growth of sheeps was promoted,feed intake and F/G were increased,growth velocity,fineness,strength,stretch length and density of wool were enhanced,and the digestibility of nutrient substance was improved.Compared with control group, the indexes above achieved significance level(p<0.05),and that were not significant among of experimental groups(p>0.05).(2)The contents of TP,ALT,AST,TC,GH,and insulin-like growth factor in blood serum were significantly enhanced by cs(p<0.05).The content of GIH in blood serum were significantly degraded by cs(p<0.05).The contents of GLU,ALB and ALP in blood serum were enhanced by cs,but it was not significant(p<0.05).(3)The abatage performance could be enhanced by each experimental groups,and living weight before killed,carcass weight,net meat weight,and meat bone ratio all achieved significance level(p<0.05) and it was not significant among of experimental groups.The quality of carcass was improved by 3 experimental groups,but it was not significant(p>0.05).In general,the effect of first experimental group(10 mg/kg·BW cs) was best.(4)Feed added 3 dose of cs,the degradation ratio of DM,NDF,ADF and cp in rumen were significantly affected.The degradation ratio of DM,NDF,ADF and cp in rumen in experimental groups were significantly higher than that in control group(p<0.05).The degradation ratio of DM,NDF,ADF and cp in rumen were highest in first experimental group.(5)In this experiment,comprehending above index,10 mg/kg·BW cs was the most suitable to be added.