Colorado State University Veterinarians Recommend Annual Rabies Vaccine for Livestock, Horses

Colorado State University veterinarians are recommending that livestock and horses be vaccinated for rabies due to an increased number of infected skunks in the state.

While bats have spread rabies in Colorado for many years, rabies spread through other wildlife has typically been more common in Eastern states. Over the last several years, more skunks in Colorado have become infected, which has resulted in an increased infection rate and risk of infection to livestock and horses. This is due in part to habitat changes and human movement of wild animals that spread the disease into areas previously uninfected.

CSU veterinarians recommend horses and livestock, particularly pet livestock such as llamas and alpacas, be vaccinated once a year, and also recommend vaccination of commercial production livestock in locations where there is high skunk activity. CSU veterinarians also strongly encourage all companion pet owners to vaccinate their cats and dogs. All warm-blooded animals, including humans, can be infected with rabies.

“While livestock or horses contracting rabies is still uncommon in Colorado, it is extremely important – now more than ever – to work to prevent animals from contracting the disease,” said Dr. Bruce Connally, a veterinarian with Colorado State University’s equine section. “It’s important because, if an animal is exposed to rabies, the symptoms can be difficult to distinguish from other illnesses, and while it is being diagnosed, the animal and people exposed to it are at risk of contracting the disease.”

Wounds from a rabid skunk bite may not be visible or easy to detect on livestock or horses, and symptoms of rabies mimic other more common illnesses and could be confused with regular colic or a foot or leg injury. Rabies also can enter the body through cuts or scratches. Rabies can be spread to people through contact with saliva or bodily fluids.

“A rabies bite to an animal that has not been vaccinated is invariably fatal,” Connally said. “The animals — horses and livestock — will die. If you value them, invest in a vaccine.”

Cases of rabid skunks biting horses or livestock have to date been limited to the area near south Denver and the eastern plains. However, due to the continued spread of the disease in skunks, it is important for anyone in Colorado to vaccinate animals that could be exposed.

Signs of rabies in animals include:
– Changed or altered behavior
– Acting nervous or agitated
– Vicious, unprovoked attacks
– Excessive salivation and difficulty swallowing
– Roaming or separation from the herd
– Unusual sexual activity
– Abnormal vocalizations
– Ascending paralysis, normally beginning in the hind limbs
– Signs of colic such as lying down more than usual or getting up and lying down repeatedly, rolling, standing stretched out, repeatedly curling the upper lip, pawing the ground and kicking at the abdomen
– Depression
– Self mutilation
– Sensitivity to light

Vaccines range in price for different animals. Cattle vaccines are available for less than $5 each, and horse vaccines range from $10 to $15, depending upon the number of animals vaccinated. Rabies vaccinations last for a year.

While vaccines have been approved for use in horses and cattle, no vaccines are approved for use in camelids, a group of animals which includes alpacas and llamas. However, camelids may still be effectively vaccinated with any vaccine labeled for sheep or cattle. Due to the lack of formal government approval on the vaccine, state veterinary and public health officials may still treat camelids as non-vaccinated animals during an incident. CSU veterinarians recommend that camelid owners consult with their veterinarian before beginning a rabies vaccination program for their animals.

Rabies vaccines do not have to be administered to livestock or horses by a veterinarian, but animals not vaccinated by a veterinarian may be treated differently by officials who respond to a potential rabies case.

“If the vaccinations for cattle, sheep and goats are given by a veterinarian and proper records are kept, then those animals should be considered rabies vaccinated by Public Health officials if there is exposure. Vaccinations can be given by the producer in order to save cost but animals may not be considered rabies vaccinated if exposure occurs,” said Dr. Rob Callan, head of the university’s livestock veterinary service. “This distinction affects the length of quarantine and how animals are handled after exposure.”

Anyone who suspects that an animal in their care may have been infected with rabies should immediately do the following:
– If an infected skunk, bat, raccoon or dog has been identified that may be transmitting the disease to other animals, do not handle or get near that animal or that animal’s carcass. If possible, safely secure its body; veterinarians can submit the body to test it for rabies.
– Immediately call a veterinarian. A veterinarian can immediately begin to assess the situation and contain the spread of the disease.
– Limit human and other animal contact with any possible exposed animals.
– Most animals die from rabies within 10 days of developing signs of an infection.
To reduce the chances of livestock, pets or human exposure to rabies:
– Do not feed or handle wildlife
– Do not relocate rabies reservoir species such as skunks or raccoons
– Exclude bats from homes, barns and other outbuildings
– Rabies virus does not live for long periods outside of a human or animal and is easily destroyed by soap and water or common household disinfectants.

For information on human rabies illness, see or For information on what to do if you have been bit by an unvaccinated animal or suspect you have otherwise been exposed to rabies, call your local health department.