Lots of homesteads and small farms have no vaccination programs. We were part of that population. It didn't seem necessary given our small number of animals. This seemed to work for us, until it didn't.
This spring we moved our sows and gilts to pasture. They had a great time tearing up the pasture and rooting through all the soil. Three of our girls went into heat and we artificially inseminated them. About half way through gestation, one of the girls miscarried. She delivered 11 partially developed piglets. The other two girls farrowed on time, but their litters were small and the piglets were not as healthy as previous litters. We should have 30-35 piglets growing and running around right now, but we only have one. ONE.
This is when we started looking into all the things that could cause problems and all the vaccines that could prevent problems. Did you know:
Leptospirosis can be a serious reproductive disease of pigs that can also cause major (non-reproductive) illness in humans. Leptospirosis causes abortion, stillborn and weak piglets and deaths soon after birth. It can be found in soil and can be transported by rodents. Both are plentiful on the farm.
Erysipelis can cause inappetence, infertility, some piglets may die in the womb following sub-acute disease and become mummified, or abortion with ill sows and dead piglets. It can be carried by birds and can live outside the pig for several weeks. A bird could carry the disease from one farm to another. Unfortunately there isn't a way to control the birds.
Porcine Reproductive Respiratory Syndrome (PRRS) can cause ALL KINDS of trouble. We were specifically looking at reproductive problems including, mummified piglets (10-15% may die in the last 3-4 weeks of pregnancy), increase in stillbirths, small and weak piglets. PRRS can be spread via airborne transmission and can travel 2 miles. Since we are only 1/2 mile from the highway, a truck hauling infected pigs could potentially infect our herd. It can also be transmitted from farm to farm on boots, clothing, etc.
Fortunately we live close to Iowa State University and were able to have necropsies done on some of our piglets. We were able to get a definitive diagnosis and change the way we did some things.
There are so many things that can make our pigs sick and so many methods of transmission. While we still try and use natural methods like good hygeine, essential oils, and high quality feed, but we also have a vaccine program in place.