The exfoliation rate of mammary epithelial cells (MECs) in milk is affected by physiological, breeding and environmental factors. Little is known about the relationship between the MEC exfoliation into milk and mammary-infected Staphylococcus aureus (S. aureus) load on bovine mastitis caused by S. aureus. The aim of this study was to investigate the relationship between S. aureus load and the proportion of MEC exfoliation in milk using five substantial bovine mastitis models. In 64 randomly extracted milk samples from udders at 3-21 days after S. aureus infusion, there were various samples with different numbers of S. aureus counts and somatic cell counts. No significant correlations were found between the S. aureus counts and somatic cell count (r = 0.338). In contrast, a significant correlation was noted between S. aureus counts and the proportion of cytokeratin-positive cells in the milk from the infused udders (r = 0.734, P < 0.01). In conclusion, the increasing MEC exfoliation rate in milk from mastitis udders caused by S. aureus may contribute to reduced milk yield.

中文翻译：

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在金黄色葡萄球菌引起的乳腺炎中，牛奶中乳腺上皮细胞的脱落率与细菌负荷有关。

牛奶中的乳腺上皮细胞（MECs）的脱落速度受生理，繁殖和环境因素的影响。关于牛奶中的MEC剥落与由金黄色葡萄球菌引起的乳腺感染的金黄色葡萄球菌（金黄色葡萄球菌）负荷之间的关系鲜为人知。这项研究的目的是使用五个基本的牛乳腺炎模型研究金黄色葡萄球菌负荷与牛奶中MEC剥脱比例之间的关系。在输注金黄色葡萄球菌后3-21天从乳房中随机抽取的64个牛奶样本中，有不同样本的金黄色葡萄球菌计数和体细胞计数不同。在金黄色葡萄球菌计数与体细胞计数之间未发现显着相关性（r = 0.338）。相反，注意到S之间存在显着的相关性。注入乳汁的牛奶中金黄色葡萄球的数量和细胞角蛋白阳性细胞的比例（r = 0.734，P <0.01）。总之，由金黄色葡萄球菌引起的乳腺炎乳房中的牛奶中MEC脱落率增加，可能会导致牛奶产量下降。