Park Y W, Humphrey R D
J Dairy Sci. 1986 Jan;69(1):32-7. doi: 10.3168/jds.S0022-0302(86)80366-6.
Representative milk samples at morning and afternoon milking were collected periodically for 5 mo from 32 does in a Prairie View A&M University milking herd to test the concentrations of total bacterial, coliform, and staphylococcus counts and to determine the correlations among the bacterial cell counts, somatic cell counts, percent fat, and percent protein. Bacterial cell counts were assayed by microbiogical methods using different nutrient media for the three cell types. Somatic cell counts were determined by an automated fluorescent microscopic somatic cell counter. Percent fat and protein were analyzed by an automated dual beam infrared absorption analyzer. Mean counts for total bacterial, coliform, staphylococcus, and somatic cell were 2.54 X 10(4), .966 X 10(3), 3.32 X 10(3), and 9.08 X 10(5) cells/ml, respectively. The Nubian goats had higher counts in all three bacterial cell types than the Alpines, and the difference in staphylococcus counts between breeds was significant (P less than .05). However, Alpine milk contained slightly higher somatic cell counts than the Nubians. None of the correlation coefficients (r) between somatic cell and bacterial cell counts was significant for the pooled data from the two breeds, but r between staphylococcus and somatic cell counts for Alpine breed was significant (P less than .05). The r between somatic cell counts and percent fat or protein were significant (P less than .01) for combined or separated breed data. Bacterial cell counts could not explain high somatic cell counts in the goat milk with the present testing standards of cow milk.
在5个月的时间里，定期采集位于普雷里维尤农工大学挤奶群中的32只母羊上午和下午挤奶时的代表性乳样，以检测总细菌、大肠菌群和葡萄球菌计数的浓度，并确定细菌细胞计数、体细胞计数、脂肪百分比和蛋白质百分比之间的相关性。使用针对三种细胞类型的不同营养培养基，通过微生物学方法测定细菌细胞计数。通过自动荧光显微镜体细胞计数器测定体细胞计数。脂肪百分比和蛋白质百分比通过自动双光束红外吸收分析仪进行分析。总细菌、大肠菌群、葡萄球菌和体细胞的平均计数分别为2.54×10⁴、0.966×10³、3.32×10³和9.08×10⁵个细胞/毫升。努比亚山羊在所有三种细菌细胞类型中的计数均高于阿尔卑斯山羊，且两个品种之间葡萄球菌计数的差异具有显著性（P<0.05）。然而，阿尔卑斯山羊奶中的体细胞计数略高于努比亚山羊奶。对于两个品种的汇总数据，体细胞计数与细菌细胞计数之间的相关系数（r）均无显著性，但阿尔卑斯山羊品种中葡萄球菌与体细胞计数之间的r具有显著性（P<0.05）。对于合并或分开的品种数据，体细胞计数与脂肪百分比或蛋白质百分比之间的r具有显著性（P<0.01）。按照目前牛奶的检测标准，细菌细胞计数无法解释山羊奶中高体细胞计数的现象。
