Department of Microbiology and Immunology, Faculty of Cs. Ex. Fco-Qcas y Naturales, University of Río Cuarto, Córdoba, Argentina.
Member of Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Buenos Aires, Argentina.
J Appl Microbiol. 2022 Aug;133(2):733-742. doi: 10.1111/jam.15604. Epub 2022 May 9.
The present work assessed the ability of two selected lactic acid bacteria (LAB) strains (Schleiferilactobacillus perolens CRL1724 and Lactococcus lactis subsp. lactis CRL1655) to inhibit the adherence of bovine mastitis pathogens to mammary epithelial cells (MAC-T) and their effects (if any) on the structure of the gland after intramammary inoculation at dry-off.
Established bovine mammary epithelial cells (MAC-T) were used to assess the LAB strains' ability to inhibit the adherence of bovine mastitis pathogens. Monolayers of MAC-T cells were co-cultured with the LABs and then individual pathogen was added. Both strains prevented the adherence of S. aureus RC108, S. chromogenes, S. uberis UT102 and E. coli ATCC 35218. Adherence of the latter two pathogens was inhibited most strongly in vitro. To evaluate the effect of the LAB on the structure of the bovine udders, quarters were intramammary inoculated with the LAB mixture at dry-off. After slaughtering, the teats were dissected and histopathologically analysed. No modifications were identified post-inoculation in the structure of the epithelial, subepithelial and connective tissues of the mammary gland.
Probiotic strains L. lactis subsp lactis CRL1655 and S. perolens CRL1724 were both able to inhibit the adherence of a number of bovine mastitis pathogens in vitro, and that the intramammary inoculation of these strains at the established dose and concentration did not cause significant alterations in the mammary epithelium nor had undesirable effects on tissues, and may therefore be considered harmless.
The promising findings demonstrated in this work support the potential of probiotic micro-organisms as a natural and effective alternative to prevent bovine mastitis during the dry-off period.
本研究评估了两种选定的乳酸菌（LAB）菌株（Schleiferilactobacillus perolens CRL1724 和 Lactococcus lactis subsp. lactis CRL1655）抑制牛乳腺炎病原体与乳腺上皮细胞（MAC-T）黏附的能力及其在干奶期经乳腺内接种后对乳腺结构的影响（如果有影响的话）。
使用已建立的牛乳腺上皮细胞（MAC-T）来评估 LAB 菌株抑制牛乳腺炎病原体黏附的能力。将 MAC-T 细胞单层与 LAB 共培养，然后加入单个病原体。两种菌株均能阻止金黄色葡萄球菌 RC108、产色葡萄球菌、停乳链球菌 UT102 和大肠杆菌 ATCC 35218 的黏附。体外对后两种病原体的黏附抑制作用最强。为了评估 LAB 对牛乳房结构的影响，在干奶期将 LAB 混合物经乳腺内接种到牛乳房 quarters 中。屠宰后，将乳头解剖并进行组织病理学分析。接种后，乳腺上皮、上皮下和结缔组织的结构未发生变化。
益生菌菌株 Lactococcus lactis subsp lactis CRL1655 和 Schleiferilactobacillus perolens CRL1724 均能抑制体外多种牛乳腺炎病原体的黏附，并且在既定剂量和浓度下经乳腺内接种这些菌株不会引起乳腺上皮的显著改变，也不会对组织产生不良影响，因此可以被认为是无害的。
本研究中得出的有希望的发现支持了益生菌微生物作为一种天然有效的替代物，在干奶期预防牛乳腺炎的潜力。
