The aim of this study was to examine the effects of milking cessation under different inflammatory conditions on the changes in antimicrobial components in milk and the process of mammary gland involution. Twenty udder halves were divided into two groups: those with (LPS) and without (control) lipopolysaccharide infusion, followed by cessation of milking for 8 weeks. Milk samples were collected weekly. Udder tissue was collected 4 weeks after milking cessation to measure the area of the lobule and connective tissue. After milking cessation, the somatic cell count (SCC) in the control group increased, whereas that in the LPS group did not. Lactoferrin (LF) and cathelicidin (Cath)-2 concentrations increased in both groups, whereas only LF was significantly lower in the LPS group than in the control group at week 4. The Cath-7 and S100A8 concentrations were significantly lower in the LPS group than in the control group. The lobule area was higher, and the connective tissue area was lower in the LPS group than in the control group. These results indicate that inflammation at milking cessation decreased the concentrations of some antimicrobial components and interfered with mammary gland involution. Therefore, animals with mastitis should recover prior to the onset of the dry period.

中文翻译：

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不同炎症状态对停奶后山羊乳房乳汁抗菌成分的影响

本研究的目的是探讨不同炎症条件下停止挤奶对乳汁抗菌成分变化和乳腺复旧过程的影响。将二十个乳房分成两组：有（LPS）和没有（对照）脂多糖输注的组，然后停止挤奶8周。每周收集牛奶样品。停止挤奶4周后收集乳房组织以测量小叶和结缔组织的面积。停止挤奶后，对照组的体细胞计数（SCC）增加，而LPS组的体细胞计数没有增加。第4周时，两组中乳铁蛋白（LF）和导管素（Cath）-2浓度均增加，而LPS组中只有LF显着低于对照组。LPS组中Cath-7和S100A8浓度显着降低比对照组。 LPS组的小叶面积高于对照组，而结缔组织面积低于对照组。这些结果表明，停止挤奶时的炎症降低了一些抗菌成分的浓度，并干扰乳腺复旧。因此，患有乳腺炎的动物应该在干奶期开始之前康复。