Davies Livestock Research Centre, School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia; Faculty of Animal Science, Vietnam National University of Agriculture, Trau Quy, Gia Lam, Hanoi, Vietnam.
Davies Livestock Research Centre, School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia; Gambier Vets, Mount Gambier, SA 5290, Australia.
J Dairy Sci. 2021 Jul;104(7):8164-8176. doi: 10.3168/jds.2020-19318. Epub 2021 Apr 15.
Colostrum is essential for good neonate health; however, it is not known whether different calves absorb the nutrients from colostrum equally well. In this study, the absorption of protein, IgG, and γ-glutamyl transferase was compared in newborn dairy bull calves for 1 wk after feeding colostrum from different sources. Thirty-five Holstein-Friesian bull calves were randomly allocated into 3 groups and fed colostrum within 4 h after birth. Group A calves (n = 12) were bottle fed colostrum from their own dam for 3 d. Colostrum from these group A cows was also used as foster cow colostrum for the group B calves (n = 12), such that each group A and B calf pair received identical colostrum from each milking of the respective group A dam (10% of birth weight per day). The group C calves (n = 11) were fed 1 bottle (2 L) of pooled colostrum and transition milk (referred to as pooled colostrum), as was the standard practice on the dairy farm. The pooled colostrum was collected from the other dairy cows on the farm 0 to 4 d postpartum and stored at 4°C for less than 12 h. Blood was sampled from calves before the first feeding and at 1, 2, 3, and 7 d after birth. Levels of total solids, total protein, and IgG were higher in the dam colostrum than in the pooled colostrum. At birth, there were no differences between the calf groups for any measurements, and all calves had very low IgG levels. After receiving colostrum, the glucose, plasma γ-glutamyl transferase, serum total protein, and IgG concentrations increased significantly in all calves. There were no differences in any blood measurements at any time point between the pairs of group A and group B calves that received colostrum from the same cow except for the IgG concentration 2 d after birth. However, the group A calves had a higher total serum protein level and IgG concentration than the group C calves for all the time points after the first feeding. The group B calves had a higher IgG concentration than the group C calves on d 1, 2, and 7 after birth. Compared with groups A and B, there was no difference in the proportion of calves in group C that failed to have passive immunity transferred adequately based on the IgG threshold (<10 g/L). Thus, the calves receiving identical colostrum from the same cow had the same levels of IgG, and even the pooled colostrum provided sufficient transfer of IgG as the calves were fed within 4 h after birth.
初乳对新生儿健康至关重要；然而，目前尚不清楚不同的小牛是否能同样好地吸收初乳中的营养物质。在这项研究中，我们比较了 35 头荷斯坦-弗里生公牛犊在出生后 1 周内从不同来源的初乳中吸收蛋白质、IgG 和γ-谷氨酰转移酶的情况。35 头荷斯坦-弗里生公牛犊随机分为 3 组，在出生后 4 小时内喂养初乳。A 组（n=12）的小牛通过奶瓶喂养来自其自身母牛的初乳 3 天。来自这些 A 组母牛的初乳也被用作 B 组（n=12）的寄养牛初乳，使得每组 A 和 B 小牛对从各自 A 组母牛的每次挤奶中获得相同的初乳（每天 10%的初生体重）。C 组（n=11）的小牛通过 1 瓶（2 L）的混合初乳和过渡奶（称为混合初乳）进行喂养，这是奶牛场的标准做法。混合初乳是从奶牛场产后 0-4 天的其他奶牛身上采集的，在 4°C 下储存不到 12 小时。在第一次喂养前和出生后 1、2、3 和 7 天从小牛身上抽取血液样本。胎牛初乳的总固体、总蛋白和 IgG 水平均高于混合初乳。出生时，3 组小牛在任何测量指标上均无差异，且所有小牛的 IgG 水平均非常低。在接受初乳后，所有小牛的血糖、血浆γ-谷氨酰转移酶、血清总蛋白和 IgG 浓度均显著升高。在任何时间点，来自同一头牛的 A 组和 B 组小牛之间的任何血液测量值均无差异，除了出生后 2 天的 IgG 浓度。然而，在第一次喂养后的所有时间点，A 组小牛的血清总蛋白水平和 IgG 浓度均高于 C 组小牛。B 组小牛的 IgG 浓度在出生后 1、2 和 7 天高于 C 组小牛。与 A 组和 B 组相比，C 组中未能根据 IgG 阈值（<10 g/L）充分转移被动免疫的小牛比例没有差异。因此，从同一头母牛获得相同初乳的小牛具有相同的 IgG 水平，甚至在小牛出生后 4 小时内进行喂养时，混合初乳也能充分转移 IgG。
