Miller R H, Paape M J, Dulin A M, Schultze W D, Weinland B T, Pearson R E
J Dairy Sci. 1985 Nov;68(11):3087-94. doi: 10.3168/jds.S0022-0302(85)81208-X.
Milk samples from quarters were collected from 48 Holstein cows at 1.5, 3, 21, and 35 wk postpartum and at 1 wk after drying off. Foremilk samples were obtained for bacteriological examination, somatic cell count of milk, and for assay of phagocytosis. Thirty-two cows in first lactation and 16 in third lactation produced by two criteria of sire selection (high milk versus multiple trait) were studied. In vitro phagocytosis was assayed four times on each original quarter milk sample, yielding 3,840 determinations. Variance components were large for cow-associated variation. Cow, stage X cow, and cow X sample dilution were 18.7, 20.6, and 6.0% of total variance. Phagocytosis was 9% higher in skim milk from third lactations than from first. Phagocytosis was highest in dry period samples, followed by 1.5, 35, 3, and 21-wk postpartum samples. Milk somatic cell count tended to be related more closely to phagocytosis than was current bacteriological status of the quarter. Skim milk from genetically higher producing cows was less conducive to phagocytosis than skim milk from genetically lower producing cows, possibly because of dilution.
在产后1.5周、3周、21周、35周以及干奶1周时，从48头荷斯坦奶牛的各个乳区采集奶样。采集前奶样用于细菌学检查、牛奶体细胞计数以及吞噬作用测定。研究了通过两种 sire 选择标准（高奶量与多性状）产生的32头头胎奶牛和16头三胎奶牛。对每个原始乳区奶样进行四次体外吞噬作用测定，共得到3840个测定值。与奶牛相关的变异的方差成分很大。奶牛、阶段×奶牛以及奶牛×样品稀释度分别占总方差的18.7%、20.6%和6.0%。三胎奶牛的脱脂奶中的吞噬作用比头胎奶牛的高9%。干奶期样品中的吞噬作用最高，其次是产后1.5周、35周、3周和21周的样品。与当前乳区的细菌学状况相比，牛奶体细胞计数与吞噬作用的关系似乎更密切。遗传产奶量较高的奶牛的脱脂奶比遗传产奶量较低的奶牛的脱脂奶对吞噬作用的促进作用更小，这可能是由于稀释的原因。
