Barłowska J, Litwińiczuk Z, Wolanciuk A, Brodziak A
Department of Commodity Science and Processing of Animal Raw Materials, University of Life Sciences, Akademicka 13, 20-950 Lublin, Poland.
Pol J Vet Sci. 2009;12(1):75-9.
The aim of the present study was to determine a relationship between the somatic cell count in milk and daily yield, chemical content as well milk technological usefulness in different breeds cows. The examinations included a total of 1867 milk samples collected from cows of four breeds: Polish Holstein-Friesian, Black-White variety--712 and Red-White variety--356, Simental--587 and Whitebacks--212 samples. Each sample was examined to determine somatic cells count (SCC), basic chemical composition, thermostability and rennet milk coagulation time. Based on the SCC score, within each cow breed, the milk samples were classified into one of four groups, i.e., I--up to 200,000 cells/ml, II--200,001-400,000 cells/ml, III--400,001-1,000,000 cells/ml and IV above 1,000,000 cells/ml. The increase in SCC was associated with the reduction in daily milk yield of the high-yielding dairy cows. As far as milk composition is concerned, an increased SCC level was connected with raise in a total crude protein content and a distinct reduction in lactose level (P < or = 0.01) as well as with a small (P < or = 0.05) increase in fat and casein content, and elevation in protein to fat ratio. The time of milk enzymatic coagulation also was lengthened (P < or = 0.01) but it did not influence its thermostability. The significant relationship (breed x SCC) for the protein, casein and lactose content, protein to fat ratio as well as rennet milk coagulation time has been revealed.
本研究的目的是确定牛奶中的体细胞计数与不同品种奶牛的日产量、化学组成以及牛奶技术实用性之间的关系。检测共包括从四个品种奶牛采集的1867份牛奶样本：波兰荷斯坦-弗里生奶牛，黑白花色——712份样本，红白花色——356份样本，西门塔尔牛——587份样本，以及白背牛——212份样本。对每份样本进行检测，以确定体细胞计数（SCC）、基本化学组成、热稳定性和凝乳酶凝乳时间。根据SCC评分，在每个奶牛品种内，将牛奶样本分为四组之一，即I组——每毫升200,000个细胞以下，II组——200,001 - 400,000个细胞/毫升，III组——400,001 - 1,000,000个细胞/毫升，IV组——每毫升1,000,000个细胞以上。SCC的增加与高产奶牛日奶产量的降低相关。就牛奶组成而言，SCC水平的升高与总粗蛋白含量的增加、乳糖水平的显著降低（P≤0.01）以及脂肪和酪蛋白含量的小幅增加（P≤0.05）以及蛋白脂肪比的升高有关。牛奶酶促凝乳时间也延长了（P≤0.01），但未影响其热稳定性。已揭示了蛋白质、酪蛋白和乳糖含量、蛋白脂肪比以及凝乳酶凝乳时间的显著关系（品种×SCC）。
