Cell Biology and Immunology Group, Wageningen University, Wageningen, the Netherlands.
J Dairy Sci. 2010 Nov;93(11):5467-73. doi: 10.3168/jds.2010-3264.
Defense mechanisms of dairy cows against diseases partly rest on their naturally present disease resistance capacity. Natural antibodies (NAb) form a soluble part of the innate immune system, being defined as antibodies circulating in animals without prior intentional antigenic stimulation. Genetic selection on NAb titers in milk, therefore, might improve disease resistance. We estimated genetic parameters of NAb titers binding lipopolysaccharide, lipoteichoic acid (LTA), peptidoglycan, and keyhole limpet hemocyanin, and titers of the NAb isotypes IgG1, IgM, and IgA binding LTA in milk of Dutch Holstein-Friesian heifers. Natural antibody titers were measured in 1 milk sample from each of 1,939 Holstein-Friesian heifers and used for estimating genetic parameters of NAb titers. The data show that phenotypic variation exists among heifers in NAb titers binding lipopolysaccharide, LTA, peptidoglycan, and keyhole limpet hemocyanin, and the NAb isotypes IgG1, IgM, and IgA binding LTA in milk. High genetic correlations among NAb (ranging from 0.45 to 0.99) indicated a common genetic basis for the levels of different NAb in bovine milk. Intra-herd heritability estimates for NAb ranged from 0.10 to 0.53. The results indicated that NAb levels have potential for genetic selection.
奶牛的疾病防御机制部分依赖于其天然存在的疾病抵抗力。天然抗体（NAb）是先天免疫系统的可溶性部分，定义为在没有事先有意抗原刺激的情况下循环在动物体内的抗体。因此，对牛奶中 NAb 滴度的遗传选择可能会提高疾病抵抗力。我们估计了结合脂多糖、脂磷壁酸（LTA）、肽聚糖和血蓝蛋白的 NAb 滴度以及结合 LTA 的 NAb 亚型 IgG1、IgM 和 IgA 滴度的遗传参数在荷兰荷斯坦弗里森奶牛小母牛的牛奶中。从 1939 头荷斯坦弗里森小母牛中的每头牛的 1 份牛奶样本中测量了天然抗体滴度，并用于估计 NAb 滴度的遗传参数。数据表明，小母牛之间存在结合脂多糖、LTA、肽聚糖和血蓝蛋白的 NAb 滴度以及结合 LTA 的 NAb 亚型 IgG1、IgM 和 IgA 滴度的表型变异。NAb 之间存在高度的遗传相关性（范围为 0.45 至 0.99），表明牛牛奶中不同 NAb 的水平具有共同的遗传基础。NAb 的个体内遗传力估计值范围为 0.10 至 0.53。结果表明，NAb 水平具有遗传选择的潜力。
