Intrauterine immunization – a novel approach to induce mucosal immunity in the reproductive tract

Project Team: Heather L. Wilson, Pooja Choudhary, Donaldson Magloire, Siew Hon Ng, and Zahed Khatooni with George K. Mutwiri, Azita Haddadi, Ramin Mohammadi

Newborn piglets are entirely dependent on colostrum and mature milk to protect them against disease until their immune systems become strong enough to warrant their own protective responses (generally at weaning). Currently, many pig vaccines are administered via the intramuscular route and require two doses to be effective. With the removal of gestation stalls, intramuscular vaccination of gilts and sows prior to entering farrowing crates is increasingly onerous, labour-intensive, and potentially dangerous for animal workers.

We have evidence that intrauterine vaccination by adding the vaccine to semen at the time of breeding may be an effective alternative strategy. The approach would take advantage of a normal husbandry practice when gilts/sows are typically stall housed for heat checking and breeding and are easily managed due to the lordosis response. Thus, intrauterine immunization may be an effective immunization route reducing labour costs, improving labourer safety, minimizing stress for the animals and will requiring only a minimal change to husbandry practices.