Franklin S T, Amaral-Phillips D M, Jackson J A, Campbell A A
Animal Sciences Department, University of Kentucky, Lexington 40546-0215, USA.
J Dairy Sci. 2003 Jun;86(6):2145-53. doi: 10.3168/jds.S0022-0302(03)73804-1.
Intake of colostrum by neonatal calves and early transition to calf starter are two important factors in successful calf programs. Thirty-one Holstein calves were used to determine health and performance of calves that were 1) allowed to remain with their dams for 3 d and suckle (suckled calves) or were removed from their dams and fed colostrum only by bottle (bottle calves); and were 2) fed ground, pelleted, or textured starters, formulated to be isonitrogenous. Bottle calves were removed from their dams at birth, fed 2.84 L of colostrum, placed in individual hutches, and fed 1.89 L of colostrum 12 h after the first feeding. Suckled calves were removed from their dams after 3 d and placed in individual hutches. Once calves were housed in hutches, they were fed 2 L of whole milk twice daily and were provided starters and water beginning on d 3. Calves were weighed at birth and weekly for 6 wk. Blood samples were obtained at birth, 24 h, and weekly for serum protein determination. Starter intake, fecal scores, and electrolyte treatments were recorded daily. Weaning began when calves had consumed 0.68 kg starter for 2 d consecutively. There were no differences in treatment means between suckled and bottle calves for total gain, grain consumption, days with fecal scores >2, or electrolyte treatments per calf. Average days to weaning was greater for bottle calves compared with suckled calves. Mean serum protein concentration at 24 h was greater for bottle (6.0 g/dl) compared with suckled calves (5.8 g/dl) and only 2 of 15 bottle calves had serum protein concentrations <5.0 g/dl compared with 6 of 16 suckled calves. For starter treatments, calves fed textured starter consumed more total grain, were weaned earlier, and weighed more at 6 wk of age than calves fed pelleted starter. Based on 24-h serum protein concentrations, transfer of passive immunity was greater for bottle calves compared with suckled calves.
新生犊牛摄入初乳以及尽早过渡到犊牛开食料是犊牛饲养计划成功的两个重要因素。选用31头荷斯坦犊牛来确定以下两类犊牛的健康状况和生长性能:1)允许与母牛待在一起3天并进行哺乳的犊牛(哺乳犊牛),或与母牛分离并仅通过奶瓶饲喂初乳的犊牛(奶瓶饲喂犊牛);2)饲喂磨碎的、颗粒状的或经加工处理的等氮开食料的犊牛。奶瓶饲喂犊牛出生时即与母牛分离,饲喂2.84升初乳,放入单独的畜栏中,并在首次饲喂12小时后再饲喂1.89升初乳。哺乳犊牛在3天后与母牛分离,放入单独的畜栏中。犊牛一旦被安置在畜栏中,每天两次饲喂2升全脂牛奶,并从第3天开始提供开食料和水。犊牛在出生时称重,之后每周称重一次,持续6周。在出生时、24小时时以及每周采集血样以测定血清蛋白。每天记录开食料摄入量、粪便评分和电解质处理情况。当犊牛连续两天摄入0.68千克开食料时开始断奶。哺乳犊牛和奶瓶饲喂犊牛在总增重、谷物消耗量、粪便评分>2的天数或每头犊牛的电解质处理方面,处理均值没有差异。与哺乳犊牛相比,奶瓶饲喂犊牛的平均断奶天数更长。奶瓶饲喂犊牛在24小时时的平均血清蛋白浓度(6.0克/分升)高于哺乳犊牛(5.8克/分升),15头奶瓶饲喂犊牛中只有两头血清蛋白浓度<5.0克/分升,而16头哺乳犊牛中有6头血清蛋白浓度<5.0克/分升。对于开食料处理,与饲喂颗粒状开食料的犊牛相比,饲喂经加工处理开食料的犊牛消耗的总谷物更多,断奶更早,在6周龄时体重更重。基于24小时血清蛋白浓度,与哺乳犊牛相比,奶瓶饲喂犊牛的被动免疫转移效果更好。