Hugi D, Blum J W
Division of Nutrition Pathology, University of Berne, Switzerland.
Zentralbl Veterinarmed A. 1997 Apr;44(2):99-108. doi: 10.1111/j.1439-0442.1997.tb01091.x.
Changes of blood metabolites and hormones were studied in female breeding calves before, during and after weaning from 4 to 18 weeks of age. Calves were initially fed increasing amounts of whole milk (up to 7 kg/day in week 8 of life). Milk intake was then gradually decreased up to the age of 16 weeks, when calves were completely weaned and only fed hay and concentrates. Average daily gain was 0.85 kg. Postprandial concentrations of glucose, insulin, insulin-like growth factor-I and 3.5.3'-triiodothyronine concentrations gradually decreased (P < 0.05) with age, while those of beta-hydroxybutyrate, protein, albumin, haemoglobin and iron increased (P < 0.05). Concentrations of cholesterol transiently increased, whereas those of urea reversibly decreased. Non-esterified fatty acids, triglycerides and growth hormone did not consistently change during the duration of the study. In conclusion, changes of glucose, beta-hydroxybutyrate, haemoglobin, iron, insulin, insulin-like growth factor-I and 3.5.3'-triiodothyronine were markedly different from those usually seen in veal calves of the same age.
对4至18周龄雌性育成犊牛断奶前、断奶期间和断奶后的血液代谢物和激素变化进行了研究。犊牛最初喂食量逐渐增加的全脂牛奶（在生命的第8周时高达7千克/天）。然后，牛奶摄入量逐渐减少至16周龄，此时犊牛完全断奶，仅喂食干草和精饲料。平均日增重为0.85千克。随着年龄增长，餐后葡萄糖、胰岛素、胰岛素样生长因子-I和3,5,3'-三碘甲状腺原氨酸的浓度逐渐降低（P<0.05），而β-羟基丁酸、蛋白质、白蛋白、血红蛋白和铁的浓度升高（P<0.05）。胆固醇浓度短暂升高，而尿素浓度可逆性降低。在研究期间，非酯化脂肪酸、甘油三酯和生长激素没有持续变化。总之，葡萄糖、β-羟基丁酸、血红蛋白、铁、胰岛素、胰岛素样生长因子-I和3,5,3'-三碘甲状腺原氨酸的变化与同龄小牛肉犊通常所见的变化明显不同。
