Homework Help: Science: Biology: Rabies in Horses

Although statistics show rabies in horses is relatively uncommon, a new puppy to our farm put all of our horses at risk to this fatal disease. My name is Taylor Jepsen from the conquistador's 4-h club Clay County and I am going to discuss the causes, diagnosis, treatment and control of rabies in horses.

Rabies is a viral disease that affects the nervous system. Horses usually contract the virus from the saliva of an infected animal. This can be from a bite or saliva contaminating an open wound. Carriers can be unimmunized cats or dogs. In our area, skunks and raccoons are the primary way horse's contract rabies. Horses are very curious especially foals/weanlings, they will investigate wildlife roaming the pasture. This exposes them to bites on the nose or lips.

Incubation of the rabies virus is usually 2 to 6 weeks, but can be up to 3 months. Diagnosing rabies can be difficult because of the wide range of clinical signs. The most important thing to remember when dealing with unexplained symptoms, think rabies first. The most common sign is behavioral. Horses may become dull and depressed. A low grade fever is usually present with convulsions, increased sensitivity to the injury site and anorexia. Symptoms progress quickly over 5-7 days resulting mostly in death. Rabies is usually undiagnosed at the beginning of symptoms because the horse is still calm, alert and eating. A veterinarian will attempt to rule out other illnesses such as tetanus, botulism, lead, plant, moldy corn poisoning or trauma to the brain or spinal cord.

Positive diagnosis can only be performed post mortem threw a fluorescent anti body test to section of the brain. A positive test means treatment should be started immediately for any person who has come in contact with the rabid animal. At present time, there is no treatment for rabies. Post vaccination of the animal is not useful because the horse will die before immunity has time to develop. In humans, a series of shots is given, but this must be before the onset of symptoms. If horses had previously been immunized an immediate booster must be given. Strict quarantine and observation are mandatory. If symptoms develop, the horse must be humanely destroyed and the head sent on for diagnosis.

Horses can be vaccinated for rabies. Vaccinated should begin at 3-4 months with a booster annually. Several steps can be taken to protect your horses against rabies. First, develop a routine yearly vaccination program for the horses, cats, and dogs on your farm. Discourage adoption of wild animals as pets and be on alert for wild animals that exhibit strange behavior.

Let's review what we have learned:

Rabies is a viral infection that attacks the nervous system. Horses contract rabies through the bite or saliva of a rabid animal. Symptoms can include behavioral changes, fever, convulsions and increased sensitivity to the injury. Correct diagnoses can only be obtained post mortem. There is no treatment for rabies in horses, although prevention includes a yearly vaccination program.

Because the new puppy to our farm tested positive for rabies- all 14 people who had contact with it had to be immunized with a series for 6-9 shots depending on weight. Our unimmunized barn cats had to be put to sleep. All horses had to have their boosters immediately and were quarantined for 6 months. We were lucky that none of the horses were infected. We have however learned a valuable lesson, how to detect rabies in animals, how to keep our animals safe and no more free puppies!

Homework Help: Science: Biology

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