Pisoni G, Locatelli C, Alborali L, Rosignoli C, Allodi S, Riccaboni P, Grieco V, Moroni P
Department of Veterinary Pathology, Hygiene and Public Health, University of Milan, via Celoria 10, 20133 Milan, Italy.
J Dairy Sci. 2008 Jan;91(1):136-9. doi: 10.3168/jds.2007-0477.
Nocardia spp. are an uncommon cause of mastitis, and outbreaks have typically been reported in dairy farms with poor hygienic and management conditions. The outbreak described herein involved a dairy farm with 43 lactating cows that, after a long period with low bulk milk somatic cell counts (<180,000 cells/mL), experienced an increasing incidence of clinical mastitis with bulk milk somatic cell counts greater than 300,000 cells/mL. Fifteen mastitic quarters milk samples from 9 dairy cows were found to be infected by a member of the genus Nocardia, as identified on the basis of selected phenotypic and chemotaxonomic characteristics. The isolates were confirmed as Nocardia neocaledoniensis by 16S rDNA gene sequencing. Average quarter milk somatic cell count for infected udders was 863,057 cells/mL, significantly greater than the average value in noninfected quarters (189,710 cells/mL).
诺卡氏菌属是乳腺炎的罕见病因，疫情通常发生在卫生和管理条件较差的奶牛场。本文所述的疫情涉及一个拥有43头泌乳奶牛的奶牛场，该奶牛场在长期保持较低的原料奶体细胞计数（<180,000个细胞/毫升）之后，临床乳腺炎发病率上升，原料奶体细胞计数超过300,000个细胞/毫升。根据选定的表型和化学分类特征鉴定，从9头奶牛的15个患乳腺炎乳房的牛奶样本中发现感染了诺卡氏菌属的一个成员。通过16S rDNA基因测序确认分离株为新喀里多尼亚诺卡氏菌。感染乳房的平均每个乳房体细胞计数为863,057个细胞/毫升，显著高于未感染乳房的平均值（189,710个细胞/毫升）。
