1 Department of Microbiology, Instituto de Investigaciones Biológicas 'Clemente Estable', Av Italia 3318, Montevideo, Uruguay.
2 Animal Health Unit, Instituto Nacional de Investigación Agropecuaria, Ruta 50 Km 11, Colonia, Uruguay.
Benef Microbes. 2018 Jun 15;9(4):613-624. doi: 10.3920/BM2017.0131. Epub 2018 Apr 10.
The use of native microorganisms with probiotic capacity is an alternative tool for the treatment and prevention of several diseases that affect animals, such as neonatal calf diarrhoea. The selection of probiotic strains within a collection is based on different in vitro and in vivo assays, which predict their potential. The aim of this study was to characterise a group of native Lactobacillus spp. strains isolated from faeces of healthy calves using an in vitro approach and to assess their ability to colonise the gastrointestinal tract (GIT) of calves. Native Lactobacillus spp. strains were evaluated on their capacity to survive low pH conditions and bile salts presence, biofilm formation and adhesion to both mucus and Caco-2 cells. Based on the in vitro characterisation, four strains (Lactobacillus johnsonii TP1.1, Lactobacillus reuteri TP1.3B, L. johnsonii TP1.6 and Lactobacillus amylovorus TP8.7) were selected to evaluate their capacity to colonise and persist in the GIT of calves. The assessment of enteric persistence involved an in vivo assay with oral administration of probiotics and quantification in faeces of the administered bacterial species with real-time quantitative PCR (qPCR). The study was conducted using 15 calves (1-month-old) which were divided into five groups of three animals, four of which were treated with four different selected strains and one was the control group. Strains TP1.3B and TP1.6 managed to persist in treated animals until ten days after the end of the administration period, indicating that they could be promising candidates for the design of probiotics for calves.
利用具有益生菌能力的本土微生物是治疗和预防影响动物的多种疾病（如新生犊牛腹泻）的一种替代工具。在收藏中选择益生菌菌株是基于不同的体外和体内测定，这些测定预测了它们的潜力。本研究的目的是使用体外方法对一组分离自健康犊牛粪便中的本土乳杆菌属菌株进行特征描述，并评估其在犊牛胃肠道（GIT）中定植的能力。评估了本土乳杆菌属菌株在低 pH 条件和胆汁盐存在下、生物膜形成和黏附于黏液和 Caco-2 细胞的能力。基于体外特征描述，选择了四种菌株（Lactobacillus johnsonii TP1.1、Lactobacillus reuteri TP1.3B、L. johnsonii TP1.6 和 Lactobacillus amylovorus TP8.7）来评估它们在犊牛 GIT 中定植和持续存在的能力。肠道持久性评估涉及口服给予益生菌的体内试验，并使用实时定量 PCR（qPCR）定量粪便中给予的细菌种类。该研究使用 15 头（1 月龄）犊牛进行，将其分为五组，每组 3 只，其中 4 组用 4 种不同的选定菌株处理，1 组为对照组。菌株 TP1.3B 和 TP1.6 能够在处理动物中持续存在至给药期结束后 10 天，表明它们可能是设计犊牛益生菌的有希望的候选菌株。
