IgG1 variations in the colostrum of Holstein dairy cows
IgG1 variations in the colostrum of Holstein dairy cows
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DOI：
10.1017/s1751731115001962
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发表时间：
2016-02-01
期刊：
影响因子：
3.6
通讯作者：
Guinard-Flament, J.
中科院分区：
文献类型：
--
作者：
Le Cozler, Y.;Guatteo, R.;Guinard-Flament, J.
高免疫质量的初乳（IgG 1浓度>= 50 g/l）对幼牛的健康和发育至关重要。对初乳质量的研究往往集中在外部因素，如品种，胎次或干乳期长度，但很少有集中在奶牛内的变化。在这里，我们进行了实验，以更深入地了解奶牛初乳中IgG 1浓度的奶牛内变化。试验在位于法国西部的一个实验农场进行。从每个季度的初乳和复合样品（混合四个季度）同时收集77荷斯坦奶牛产犊后立即评估IgG 1浓度的样品类型的影响。从挤奶开始每分钟采集9头奶牛的样本，研究第一次挤奶期间IgG 1浓度的变化。根据2009年和2010年16头健康奶牛的数据估计初乳IgG 1浓度的重复性。使用放射免疫扩散法检测IgG 1浓度。无论检测的样品类型（单个乳区或复合乳）如何，灵敏度和特异性均相似。复合初乳中平均IgG 1浓度为54.1 g/l，后乳区乳头（562 g/l）显著高于前乳区乳头（53.1 g/l）。在初乳挤奶期间，平均IgG 1浓度未发生显著变化，观察到的变化（≤ 15%）可能是由于实验室方法（CV 15%）所致。由于BW和胎次效应，2009年至2010年母鼠初乳中的IgG 1浓度略有增加。在56%的情况下，可以通过第一次挤奶期间任何时间收集的单个或混合初乳样本来评估初乳质量，而不会影响测量的可靠性。然而，在其他情况下，差异是显着的，足以意味着从任何一个季度的初乳中的平均IgG 1浓度的估计将是不可靠的。可以得出结论，初乳的质量，从IgG 1浓度的角度来看，可以评估在第一次挤奶期间的任何时间采取的复合样品。
High-immune quality colostrum (IgG1 concentration >= 50 g/l) is crucial for the health and development of the young calf. Studies on colostrum quality tend to focus on external factors such as breed, parity or dry period length, but few have focused on within-cow variations. Here we ran experiments to gain a deeper insight into within-cow variation in IgG1 concentrations in dairy cow colostrum. Trials were performed in an experimental farm, located in the Western part of France. Colostrum from each quarter and a composite sample (mix of four quarters) were concomitantly collected on 77 Holstein dairy cows just after calving to assess the influence of sample type on IgG1 concentrations. Variation in IgG1 concentrations during the first milking was studied on samples from nine cows collected every minute from the start of milking. Repeatability of colostral IgG1 concentration was estimated from 2009 and 2010 data on 16 healthy cows. IgG1 concentrations were tested using a radial immunodiffusion method. Sensitivity and specificity were similar regardless of sample type tested (individual quarter or composite milk). Mean average IgG1 concentration was 54.1 g/l in composite colostrum, and was significantly higher in hind quarter teats (562 g/l) than front quarter teats (53.1 g/l). Average IgG1 concentration did not change significantly during colostrum milking, and the variations observed (15% or less) were likely due to the laboratory method (CV 15%). IgG1 concentrations in dam colostrum increased slightly from 2009 to 2010 due to BW and parity effects. In 56% of cases, colostrum quality could have been assessed on either individual or composite colostrum samples collected at any time during the first milking without affecting the reliability of the measurement. However, in other cases, differences were significant enough to mean that estimates of average IgG1 concentration in colostrum from any one quarter would not be reliable. It is concluded that colostrum quality, from an IgG1 concentration point of view, could be assessed with a composite sample taken at any time during the first milking.