Instructions
Pay attention to what a horse is or isn't eating. Like most animals, including humans, one of the first, most obvious signs they aren't feeling well is refusing to eat. If a horse that normally eats on a regular basis suddenly stops eating, then you can assume something is wrong. In addition, if the animal is trying to eat or drink, but is having difficulty swallowing, it could be indicative of a problem more severe than a simple sore throat.
Take note of their attitude. Most horse owners know their animals' personalities, so if you see them start acting differently than the norm, this could also be a sign of illness. Depression and listlessness are noted symptoms of encephalitis. They may also wander aimlessly, walk in circles or show signs of hyperexcitability or head pressing.
Watch the way they walk. Encephalitis can affect a horse's gait. As the illness progresses, their hind legs may become weak causing them to stumble or become uncoordinated and eventually, they may suffer from paralysis of the hind limbs. Problems with their vision can also occur, which becomes noticeable if they suddenly start bumping into things.
Look for signs of severe progression of encephalitis. As the horse becomes more symptomatic, you may notice muscle tremors, convulsions or seizures. The animal may become very weak to the point it will lay down and refuse to get back up. It might also eventually slip into a coma.
Call the veterinarian. If you notice one or more of these symptoms in a horse, contact your vet and have them take blood and tissue samples. A lab can test these to confirm your suspicions.
Be on high alert if you find a dead horse. Anytime an animal dies suddenly without any obvious outward appearance of trauma, assume the culprit is internal. Take extreme precautions when handling the carcass including wearing full protective gear, and have the remains tested immediately to see what you're dealing with.
How to Diagnose Encephalitis in a Horse
A mosquito's bite, while annoying, can also be deadly, especially to a horse. Western Equine Encephalitis (WEE), Eastern Equine Encephalitis (EEE) and West Nile Virus (WNV) can all transmit to equines via a bite and cause encephalitis or swelling of the brain. Unfortunately, diagnosing isn't always easy because infected animals may never get sick, while others die quickly.