Skip to Content

The Weekly News Source for Wyoming's Ranchers, Farmers and AgriBusiness Community

Biosecurity for horses Horse owners can take precautions to ensure biosecurity

by Wyoming Livestock Roundup

Biosecurity starts by simply looking at procedures and management practices that can be done to limit exposure to disease, says Judy Marteniuk of Michigan State University’s College of Veterinary Medicine.

“These practices can limit spread of disease-causing organisms from one animal to another or from one farm to another, as certain diseases can be extremely contagious,” Marteniuk says. 

Disease pathways

For disease to occur in an animal, three stages must be considered.

“First, we have our animal. We also have some type of infectious agent and the environment,” Marteniuk comments. “Without this triad, we won’t have disease.” 

For example, if the immune system is good and the animal is healthy, a much larger amount of infectious agent is necessary to cause disease. At the same time, if the environment is very stressful, whether as a result of weather or attendance at an event, smaller concentration of infectious agents are necessary because stress suppresses the immune system.

“It’s important we have our animals as healthy as we can to minimize exposure to infectious agents,” she explains. “Unfortunately, we can’t do anything about Mother Nature and the environment, for the most part.”

Diseases are spread by fomites, and one of the most common fomites for disease spread are people.

“We have our regular clothes and boots on when we go visit other facilities, which isn’t something we should do,” Marteniuk says. “We should change our footwear and clothes because organisms can live on our clothing.”

At the same time, if a disease outbreak occurs, it’s important for horse owners to remove their clothing to minimize risk to infect other animals or even people in the household for zoonotic diseases.

“Tack can also spread disease. We tend to share tack, brushes and other equipment, which can transmit disease from one group of animals to another,” Marteniuk comments. 

Water and feed are also possible sources on infection.

Whenever water pools or ponds on the ground, it can become contaminated with fecal matter, which increases disease potential.

“When we have grain, it should be stored in something rodent-proof,” she says, noting rodents are a big cause of disease. “When we buy bags of feed, make sure they are intact. Torn bags may be contaminated by rodents.” 


To prevent disease, Marteniuk suggests starting with a current and robust vaccination program.

“The Core Five vaccines include eastern, western and West Nile Encephalitis, tetanus and rabies,” she says. “Even though these diseases are transmissible from horse to horse, they are transmissible through environmental agents, such an the soil and air. We should try and prevent our horses from contacting these infectious diseases.” 

Other vaccines that are not considered core vaccines may be necessary, particularly for horses that travel frequently. For example, flu, rhinovirus and Strangles may be a concern for horses that travel. 

In addition, when a new horse is introduced on a premises or a horse is returning from an equine event, Marteniuk says they should be quarantined, ideally.

“The equine industry makes true isolation and quarantine that would be practiced with other species much harder,” she explains. “Horses, by their nature of use, are constantly traveling and constantly being exposed to situations and disease.” 

“Biosecurity can be extremely challenging,” Marteniuk continues, “but if possible, it’s important to have a quarantine barn or a place to keep animals segregated from the main population for around 30 days.” 

To avoid disease outbreak, it is important to quarantine for longer that the incubation period, which is typically covered under a 30-day window.

New horses

“It’s also important to make sure new animals entering the farm are healthy,” she says, noting a veterinary exam, visual inspection and more are important. 

“We should make sure their vaccines are up-to-date on new horses, too,” Marteniuk adds. “Anything we can do to reduce potential infectious agents in a facility is really important.” 

Marteniuk continues that testing for contagious diseases, including equine infectious anemia tests, should also be used. 

At the same time, when new horses are brought on to a premises, it is also important to make sure resident horses are as healthy as possible so new horses aren’t more of a risk than is necessary. 

“The other thing we need to think about in terms of biosecurity is what other species are also on the farm,” Marteniuk says. “We don’t want species like rats or mice to contaminate grain, and cats and dogs going from pen to pen can also spread disease, as can birds.”

While some risks are inherent on the farm and the ranch, it is important for horse owners to be cognizant of challenges associated with other animals on the farm or ranch. 


“One of the hardest things for horse owners to control is when our horses travel because most of us don’t have isolation barns when they travel to separate populations,” Marteniuk explains. “We need to think about these aspects of how are we going to control disease and minimize the risk of disease.” 

One way to achieve a quasi-isolation is to group horses by their lifestyle. For example, broodmares should be kept separate from young horses, which should be kept separate from those horses that travel to equine events. 

“Young horses are like kindergarten kids,” she explains. “They are more susceptible to disease, and they should be kept away from other populations, particularly pregnant broodmares.” 

“If we have horses coming to our farm for a 4-H event, show or any other purpose, keeping those animals separate from the population on the farm or ranch can help to reduce disease spread, as well,” Marteniuk says. “We really need to try to keep those horses separate as much as we possibly can to improve our biosecurity and reduce the potential for disease.”

Saige Albert is managing editor of the Wyoming Livestock Roundup. Send comments on this article to

  • Posted in Special Editions
  • Comments Off on Biosecurity for horses Horse owners can take precautions to ensure biosecurity
Back to top