Your horse’s immune system can be “compared to a totalitarian state”, says Ian Tizard, author of the book, Veterinary Immunology, An Introduction. “Foreigners are expelled and citizens who behave themselves are tolerated, but those who ‘deviate’ are eliminated” he continues.
A “foreigner” entering your horse’s body is called an antigen. This is anything that elicits an immune reponse – eg. bacteria, viruses, parasites. An immune response is the police force, identifying and protecting the body from the antigen. (This is sounding a bit xenophobic, I know, but it makes the point.)
How does the immune system get rid of the antigen?
1. It must identify the antigen as foreign.
2. It must launch the immune response.This is done by cells called lymphocytes.
3. It must destroy it – either using cells (such as neutrophils or macrophages) or antibodies (mostly Immunoglobulins).
4. It must remember the antigen, so that the next time it is exposed to the same antigen, the response will be faster and more efficinent. (This is how vaccines work.)
When is the immune system compromised?
Many things can compromise this delicate system. When that happens, pathogens can enter your horse’s body and make him sick. According to Glen Gamble DVM, compromise of the immune system is almost always caused by one of these three things: stress, nutrition or age.
How do we boost the immune system?
Obviously, optimising the nutrition and minimising stress is a good start. Herbs that can help: Ginseng (an adaptogen, which helps the horse cope with stress), Echinacea (been shown in a placebo controlled double blind study to boost immunity in horses) and Garlic (outperforms antibiotics in some trials).