Department of Animal Biosciences, Animal Science and Nutrition, University of Guelph, Guelph, Ontario, Canada N1G 1Y2.
Department of Animal Biosciences, Animal Science and Nutrition, University of Guelph, Guelph, Ontario, Canada N1G 1Y2.
J Dairy Sci. 2023 May;106(5):3680-3691. doi: 10.3168/jds.2022-22518. Epub 2023 Mar 7.
Ingestion and absorption of greater quantities of IgG are required to increase serum IgG levels in newborn calves. This could be achieved by adding colostrum replacer (CR) to maternal colostrum (MC). The objective of this study was to investigate whether low and high-quality MC can be enriched with bovine dried CR to achieve adequate serum IgG levels. Male Holstein calves (n = 80; 16/treatment) with birth body weights (BW) of 40 to 52 kg were randomly enrolled to be fed 3.8 L of the following combinations: 30 g/L IgG MC (C1), 60 g/L IgG MC (C2), 90 g/L IgG MC (C3), C1 enriched with 551 g of CR (60 g/L; 30-60CR), or C2 enriched with 620 g of CR (90 g/L: 60-90CR). A subset of 40 calves (8/treatment) had a jugular catheter placed and were fed colostrum containing acetaminophen at a dose of 150 mg/kg of metabolic body weight, to estimate abomasal emptying rate per hour (kABh). Baseline blood samples were taken (0 h), followed by sequential samples at 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, and 48 h relative to initial colostrum feeding. Results for all measurements are presented in the following order, unless otherwise stated: C1, C2, C3, 30-60CR, and 60-90CR. Serum IgG levels at 24 h were different among calves fed C1, C2, C3, 30-60CR, and 60-90CR: 11.8, 24.3, 35.7, 19.9, and 26.9 mg/mL ± 1.02 (mean ± SEM), respectively. Serum IgG at 24 h increased when enriching C1 to 30-60CR, but not from C2 to 60-90CR. Similarly, apparent efficiency of absorption (AEA) values for calves fed C1, C2, C3, 30-60CR, and 60-90CR were different: 42.4, 45.1, 43.2, 36.3, and 33.4% ± 1.93, respectively. Enriching C2 to 60-90CR reduced AEA, and enriching C1 to 30-60CR tended to decrease AEA. The kABh values for C1, C2, C3, 30-60CR, and 60-90CR were also different: 0.16, 0.13, 0.11, 0.09, and 0.09 ± 0.005, respectively. Enriching C1 to 30-60CR or C2 to 60-90CR reduced kABh. However, 30-60CR and 60-90CR have similar kABh compared with a reference colostrum meal (90 g/L IgG, C3). Even though kABh was reduced for 30-60CR, results indicate that C1 has the potential to be enriched and achieve acceptable serum IgG levels at 24 h without affecting AEA.
新生犊牛需要摄入和吸收更多的 IgG 才能增加血清 IgG 水平。这可以通过在母体初乳中添加牛初乳替代品（CR）来实现。本研究的目的是探讨低质量和高质量的初乳是否可以通过添加牛初乳干燥物（CR）来富集，以达到足够的血清 IgG 水平。将出生体重为 40-52kg 的 80 头雄性荷斯坦犊牛（n=80；16/处理）随机分为以下 3.8L 组合进行喂养：30g/L IgG 初乳（C1）、60g/L IgG 初乳（C2）、90g/L IgG 初乳（C3）、用 551g CR 富集的 C1（60g/L；30-60CR）或用 620g CR 富集的 C2（90g/L：60-90CR）。40 头犊牛（8/处理）中有一部分通过颈静脉导管放置，并给予含有对乙酰氨基酚的初乳，剂量为代谢体重的 150mg/kg，以估计每小时的瘤胃排空率（kABh）。在最初的初乳喂养后 0h 采集基线血样，然后分别在 1、2、3、4、5、6、8、10、12、24、36 和 48h 进行连续采样。除非另有说明，否则所有测量结果均按以下顺序呈现：C1、C2、C3、30-60CR 和 60-90CR。24h 时，C1、C2、C3、30-60CR 和 60-90CR 喂养的犊牛血清 IgG 水平不同：11.8、24.3、35.7、19.9 和 26.9mg/mL±1.02（平均值±SEM）。用 C1 富集到 30-60CR 可提高 24h 时的血清 IgG，但用 C2 富集到 60-90CR 则不然。同样，C1、C2、C3、30-60CR 和 60-90CR 喂养的犊牛表观吸收效率（AEA）值也不同：42.4、45.1、43.2、36.3 和 33.4%±1.93。用 C2 富集到 60-90CR 降低了 AEA，用 C1 富集到 30-60CR 则降低了 AEA 的趋势。C1、C2、C3、30-60CR 和 60-90CR 的 kABh 值也不同：0.16、0.13、0.11、0.09 和 0.09±0.005。用 C1 富集到 30-60CR 或 C2 富集到 60-90CR 降低了 kABh。然而，30-60CR 和 60-90CR 与参考初乳餐（90g/L IgG，C3）的 kABh 相似。尽管 30-60CR 的 kABh 降低了，但结果表明 C1 具有富集的潜力，并能在 24h 内达到可接受的血清 IgG 水平，而不影响 AEA。
