Cellular and soluble components decrease the viable pathogen counts in milkfrom dairy cows with subclinical mastitis

The Journal of Veterinary Medical Science

Naoki ISOBE¹  Tomoko KOSHIISHI²  Keiichi HISAEDA²  Hajime MIYAKE³  Masako WATANABE⁴ 

[1] Graduate School of Biosphere Science, HiroshimaUniversity, Higashi-Hiroshima, Hiroshima 739-8528, Japan;Nanyo Veterinary Clinic, Ehime P.F.A.M.A.A. Seiyo,Ehime 797-1211, Japan;Oozu Veterinary Clinic, Ehime P.F.A.M.A.A. Oozu, Ehime795-0064, Japan;Touyo Veterinary Clinic, Ehime P.F.A.M.A.A. Saijo,Ehime 799-1312, Japan

关键词: antimicrobial components;    dairy cow;    milk;    pathogen;    somatic cell count;   

DOI  :  10.1292/jvms.17-0269

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

The present study was undertaken to clarify the factors that reduce the viable pathogencount in milk collected from the udders of subclinical mastitic cows during preservation.Milk was centrifuged to divide somatic cells (cellular components, precipitates) andantimicrobial peptides (soluble components, supernatants without fat layer); each fractionwas cultured with bacteria, and the number of viable bacteria was assessed prior to andafter culture. In 28.8% of milk samples, we noted no viable bacteria immediately aftercollection; this value increased significantly after a 5-hr incubation of milk withcellular components but not with soluble components (48.1 and 28.8%, respectively). Afterculture with cellular components, the numbers of bacteria (excludingStaphylococcus aureus and Streptococcus uberis) andyeast decreased dramatically, although the differences were not statistically significant.After cultivation with soluble components, only yeasts showed a tendency toward decreasedmean viability, whereas the mean bacterial counts of S. uberis andT. pyogenes tended to increase after 5-hr preservation with solublecomponents. These results suggest that most pathogens in high somatic cell count (SCC)milk decreased during preservation at 15 to 25°C, due to both the cellular components andantimicrobial components in the milk. Particularly, the cellular components more potentlyreduced bacterial counts during preservation.

【 授权许可】

Unknown