妊娠青山羊蛋白质需要的研究

STUDIES ON PROTEIN REQUIREMENT OF JINING GRAY DOES IN GESTATION

用前列腺素处理28只5.5月龄的青山羊母羊,使之同期发情,自然交配后分为自由和限制采食两组,进行饲养试验、屠宰试验、内源氮测定试验、消化代谢试验,以研究妊娠青山羊的蛋白质需要。试验结果表明,青山羊妊娠期前三个月,内源性尿氮(Endogenous urine nitrogen,EUN)为0.105 gN/kgW^(0.75)/d,代谢性粪氮(Metabolic fecal nitrogen,MFN)为0.159 gN/kgW^(0.75)/d;妊娠期最后两个月,EUN 为0.460 gN/kgW^(0.75)/d,MFN 为0.055 gN/kgW^(0.75)/d。胚胎、胎盘和胎水中蛋白质沉积量及沉积速度和胚胎、妊娠物增重及增重速度均符合指数曲线。妊娠青山羊的蛋白质需要 Y=0.63W^(0.75)+0.58X_1+0.72X_2,其中:Y—妊娠青山羊粗蛋白每日需要量(g):W^(0.75)—代谢体重(kg);X_1—母体本身增重(g);X_2—妊娠物增重(g)。

Twenty-eight Jining gray does of 5.5 months old were used to study the protein require- ment of the animals in pregnancy.Prostaglandin was administered to make the does synchronously oestrus.After becoming pregnant,the animals were divided into two groups,ad libitum and controlled feeding.The trails of feeding,nitrogen balance and slaughter were carried out.The protein contents of the diets in feeding trails were 13.6 and 20.0% for the first three months and the last two months of gestation,respectively.The results of the experiments showed that the maintenance requirement of protein of jining gray does in gestation is 4.63 gCP/kgW^(0.75)/day,that for weight gaining of the does theirself is 0.58gCP/g weight gain,and for the conceptus 0.72 gCP/g weight gain.The protein requirement of the jining gray does in gestation can be calcu- lated by Y=4.63W^(0.75)+0.58X_1+0.72X_2,where X_1 is the weight gain of the ewe itself,g;X2 is the weight gain of the conceptus,g.It was also found that the weight gain or protein accu- mulation in foetus and in other conceptus materials also followed exponential curves.