Immunisation of mares to control endometritis caused by Streptococcus zooepidemicus.

This study shows that inoculating horses with a relevant antigen can decrease infection of their reproductive systems caused by Streptococcus zooepidemicus bacteria, as indicated by a lower number of bacteria and reduced inflammation.

Research Objective

• The research aims to determine whether immunization can protect mares (female horses) from endometritis caused by Streptococcus zooepidemicus, a pathogenic bacteria.

Methodology

• The researchers used both intramuscular and intrauterine routes to inject an antigen mixed with an adjuvant into healthy mares.
• These immunized mares, as well as some unimmunized control mares, were subsequently exposed to pathogenic Streptococcus zooepidemicus through intrauterine instillation.
• The reactions of the mares were observed both clinically and bacteriologically over seven days.

Results

• There were significantly fewer S zooepidemicus bacteria found in the cervical swabs of the immunized mares compared to the control group (P < 0.01).
• Additionally, the inflammation experienced in the genital tracts of the immunized mares was significantly less than that in the control group (P < 0.001).
• This protective benefit of vaccination was linked to a specific IgG response in the blood, as well as IgG and IgA responses in the uterine secretions.

Significance of the Study

• This study demonstrates for the first time that pre-immunization with a suitable antigen can lower reproductive tract infections in mares.
• This is significant as it may lead to new ways to prevent such infections in horses, improving their health and potentially reducing the need for antibiotics.