What do vaccines do?
Why do we use them? Is the cost and labour involved worthwhile in my herd? Vaccines show the immune system of the pig a picture of what the disease organism looks like so that when the pig is exposed to the actual disease organism, it will be recognized easily and can then be neutralized and destroyed before disease is caused. Early recognition and destruction of the disease organism is often necessary to prevent disease. On the first exposure to the disease organism (whether in a vaccine or during the actual exposure to the virulent infectious agent) the immune system gobbles up the organism, digests it into pieces and shows these recognition pieces back to the body of the pig, telling the pig that it is a foreign substance that could do some harm if it is not destroyed. After the immune system is properly primed with enough antigen, it takes approximately 2-3 weeks to mount a full immune response because the immune system needs some time to make the recognition template (or photo alb
