The bacterium Clostridium chauvoei is the causative agent of blackleg in livestock, and vaccination is the most effective means of prevention. The aim of this study was to assess the effect of short-term supplementation with Bacillus toyonensis and Saccharomyces boulardii on the immune response to a C. chauvoei vaccine in sheep. Sheep were vaccinated subcutaneously on day 0 and received a booster dose on day 21, with 2 mL of a commercial vaccine formulated with inactivated C. chauvoei bacterin adsorbed on aluminum hydroxide. Probiotics were orally administered B. toyonensis (3 × 10⁸ cfu) and S. boulardii (3 × 10⁸ cfu) over five days prior to the first and second doses of the vaccine. Sheep supplemented with B. toyonensis and S. boulardii showed significantly higher specific IgG, IgG1, and IgG2 titers (P<0.05), with approximately 24- and 14-fold increases in total IgG levels, respectively, than the nonsupplemented group. Peripheral blood mononuclear cells from the supplemented group had increased mRNA transcription levels of the IFN-γ, IL2, and Bcl6 genes. These results demonstrate an adjuvant effect of short-term supplementation with B. toyonensis and S. boulardii on the immune response against the C. chauvoei vaccine in sheep.

细菌梭状芽孢杆菌chauvoei是在家畜黑胫的病原体，和疫苗接种是预防的最有效手段。本研究的目的是评估短期补充Bacillus toyonensis和Saccharomyces boulardii对绵羊对C. chauvoei疫苗的免疫反应的影响。绵羊在第 0 天皮下接种疫苗，并在第 21 天接受加强剂量，用 2 mL 用吸附在氢氧化铝上的灭活C.chauvoei菌苗配制的商业疫苗。益生菌口服给药B. toyonensis (3 × 10 ⁸ cfu) 和S. boulardii (3 × 10 ⁸ cfu)cfu) 在第一剂和第二剂疫苗前五天以上。补充了B. toyonensis和S. boulardii 的绵羊显示出显着更高的特异性 IgG、IgG1 和 IgG2 滴度（P < 0.05），与未补充组相比，总 IgG 水平分别增加了约 24 倍和 14 倍。补充组的外周血单核细胞增加了IFN-γ、IL2和Bcl6 基因的mRNA 转录水平。这些结果证明了短期补充B. toyonensis和S. boulardii对针对C. chauvoei的免疫反应的辅助作用 绵羊疫苗。