Oliver S P, Mitchell B A
J Dairy Sci. 1983 May;66(5):1162-6. doi: 10.3168/jds.S0022-0302(83)81913-4.
Quarter foremilk samples (1,574) were collected for bacteriological analysis from 40 cows during late lactation, early involution, prior to parturition, parturition, and during early lactation. Six of 160 quarters were infected with major pathogens during late lactation. Twelve new infections occurred during early involution. Twenty-two quarters were infected at parturition. Of these infections, 12 occurred after early involution, and 10 infections that originated during early involution persisted throughout the dry period. During early lactation, 21 major pathogen infections were observed. Nine occurred after calving, and 12 persisted from parturition. Most major pathogen infections (93.8%) were caused by coliforms and streptococcal species other than Streptococcus agalactiae. Numbers of streptococcal infections were highest at parturition and early lactation. Numbers of quarters infected with coliforms were similar during early involution, parturition, and early lactation. Coagulase negative staphylococcal infections increased during the dry period, whereas Corynebacterium bovis infected quarters decreased. Udder infections were few in cows completing first or second dry periods. The incidence of udder infection was highest in cows completing third or later dry periods.
在泌乳后期、 involution初期、分娩前、分娩期间和泌乳早期，从40头奶牛身上采集了1574份四分之一前乳样本进行细菌学分析。在泌乳后期，160个乳房象限中有6个感染了主要病原体。 involution初期出现了12例新感染。分娩时有22个乳房象限感染。在这些感染中，12例发生在involution初期之后，10例起源于involution初期的感染在整个干奶期持续存在。在泌乳早期，观察到21例主要病原体感染。9例在产犊后发生，12例从分娩时持续存在。大多数主要病原体感染（93.8%）由大肠菌群和无乳链球菌以外的链球菌引起。链球菌感染数量在分娩和泌乳早期最高。在involution初期、分娩和泌乳早期，感染大肠菌群的乳房象限数量相似。凝固酶阴性葡萄球菌感染在干奶期增加，而感染牛棒状杆菌的乳房象限减少。完成第一或第二个干奶期的奶牛乳房感染较少。完成第三个或更晚干奶期的奶牛乳房感染发生率最高。
