Abstract:

The aim of this study was to explore the therapeutic effect of Lactobacillus salivarius on latent mastitis of dairy goats, in this study, 12 dairy goats with mastitis were randomly selected, of which 6 were used as probiotic treatment group and 6 were used as mastitis model control group. Another twelve healthy dairy goats were selected, of which 6 were used as probiotics prevention group and 6 were used as blank control group. Probiotic treatment group and probiotic control group were fed Lactobacillus salivary every day, and the rest groups were not treated. The milk, anticoagulant and rectal contents of dairy goats were collected after feeding on day 0 and 28. The changes of blood inflammatory factors, intestinal flora and milk flora were detected by fluorescence quantitative PCR and 16S rRNA microflora sequencing, respectively. The results showed that the incidence of subclinical mastitis of dairy goats fed Lactobacillus salivary decreased from 36.36% to 13.64%, The relative expression levels of inflammatory factors such as IL-17, IL-1β and IL-6 were significantly decreased, while the relative expression levels of anti-inflammatory factor IL-10 were significantly increased. The microbial Alpha diversity increased in the gut and milk, and the diversity of flora increased, which significantly increased the relative abundance of Firmicutes and decreased the relative abundance of Bacteroidetes at the phylum level of intestinal microbiome, and increased the relative abundance of Firmicutes and Cyanobacteria at the phylum level of milk microbiome, and decreased the relative abundance of Proteobacteria.In conclusion, Lactobacillus salivarius has a good therapeutic effect on occult mastitis, and has a clinical prospect for the treatment of occult mastitis.

Key words: dairy goats, subclinical mastitis, Lactobacillus salivarius, intestinal flora, milk microorganisms