A new approach developed by VIDO-InterVac for vaccinating sows and gilts to protect against various diseases shows promise.
Researchers at the University of Saskatchewan are evaluating the delivery of intrauterine vaccines; administered to sows and gilts along with the semen during artificial insemination.
Dr. Heather Wilson, a research scientist with VIDO-InterVac, said most diseases that impact the adult pig also affect pregnancies, so this approach delivers vaccines directly to the uterus.
The target is diseases that impact pregnancy, so PRRS or parvovirus, circovirus, affects its health. They are still developing those disease models in Dr. Wilson’s lab.
“We have Lawsonia intracellularis, which is a disease that impacts weaner piglets,” she said. “Also administered a vaccine for PEDv, which impacts the piglets just a couple of days after birth. 
“Their research shows the intrauterine vaccine has a positive protective effect against the weaner piglets for PEDv, so, once they suckle they show signs of protection. While limited, it shows promise and some protection against the PEDv,” she said. 
Dr. Wilson said it’s still early, but with each trial, different configurations, including how much vaccine, what adjuvants used, which diseases targeted, assessed shows they learn something each time. 
She said they administer the vaccine with the semen during breeding as the animal’s cervix is permissive, or open. They insert a catheter into the cervix, and that’s where they attach a bag of semen, taken up into the animal. The vaccine goes directly into the semen bag, invert it a couple of times to mix it up, and administered directly into the uterus.
Dr. Wilson said the challenges are to make sure it works and not have any negative impact on the semen or the piglets or the sow’s reproductive health. It’s interesting to get the producers excited and willing to take it up as an unusual idea.
Also, she thinks they can show it works well; it could interest semen producers and consider marketing the semen to protect offspring, sows, and the gilt against disease.
The significant advantage Dr. Wilson believes is administering the vaccine during breeding combines several functions most likely appreciated by the barn staff. Also, to target the vaccine precisely where it needs to protect the uterus, preventing many fetal deaths and preventing the disease from taking hold in the sows and the gilts. •
— By Harry Siemens