Biosecurity is important on any farm, as it helps control what enters the property and what moves throughout the property.

Dr. Carolyn Hurwitz, a Maine veterinarian, described biosecurity as “a security system that’s designed to protect against biological threats.” There are many levels of biosecurity, and the system can be as simple or as complex as your farm and facility needs it to be.

A farm’s current risk tolerance influences the complexity of the biosecurity system. Risk tolerance is “very individualized and variable,” constantly changing based on threats, priorities and available resources. A farm’s priorities could be based on the animals’ well-being, protecting their business investment or following regulatory compliance protocols.

One important aspect of biosecurity is quarantining – separating an exposed or assumed-exposed animal from the rest of the herd. “It is extremely easy and it’s a very high-value tool to implement,” Hurwitz said. By implementing just a couple key practices, you can help keep your animals safe and healthy.

Introducing New Animals

One critical time to quarantine is when introducing a new or unknown animal to an existing herd. This introduction can pose “some of the highest risks to the farm’s biosecurity.” An immediate quarantine period prevents the unknown animals from bringing infectious disease to the known animals by disrupting the disease transmission pathway.

The disease transmission pathway includes exposure, incubation, disease and recovery (or possibly death). For the most part, animals are the most contagious in the disease period, when they are displaying signs of sickness such as sneezing, coughing, watery eyes and diarrhea. These fluids are highly concentrated with the infective organism, making them easy to spread with close contact. Some diseases begin to spread in the incubation period, and some even continue to spread throughout the recovery period.

There are five main ways animals can be exposed to disease: the fecal-oral route, the aerosol route, direct contact, fomites and vectors. The first three require close contact between the infected animal and the soon-to-be exposed animal. By creating physical boundaries between them, we hope to prevent that exposure in the first place.

Fomites are nonliving objects that can carry disease on their surfaces, which can be prevented through proper management and disinfectants. Vectors (like ticks or rats) are harder to control, but doable with further biosecurity.

The length of the quarantine period depends on the potential disease present. If the potential disease has a long incubation period (time between exposure and showing signs of illness) or a long carrier period (animal has recovered but is still contagious), the animals will need a longer quarantine. An average quarantine is 21 – 28 days, but longer is recommended if the animal’s health history is unknown.

A Good Quarantine Facility

A quarantine facility is most effective when located at least two miles from the resident animals, but that’s not always possible. The next best thing is to create a new pen or building specifically made for quarantining, ideally downwind from the rest of the herd. The pen should be far enough away to prevent nose-to-nose contact with the healthy herd, and to limit unnecessary foot or vehicular traffic through the quarantine area.

Carol Delaney, the livestock specialist for the Animal Health Program at the Maine Department of Agriculture, Conservation & Forestry, listed some standard practices to follow in your quarantine pen:

  • Post signage outside the building to limit traffic flow
  • Make sure each animal is easily identifiable
  • Feed the quarantined animals separately, and after the healthy animals
  • Train your workers on how to monitor for signs of sickness
  • Any dirty bedding being removed from the pen should be placed in a separate compost pile – don’t mix with the bedding from healthy animals
  • Layer on even more biosecurity tools, such as surveillance testing, or only purchase animals from herd certification programs
  • Have a plan for mortality

“No one wants it to happen, but it’s something you need to consider,” explained Delaney.

In order to limit fomites, Delaney recommended keeping specific products, tools and supplies to be used exclusively in the quarantine area. These include coveralls, gloves, boots, cleaning tools, wheelbarrows, brushes, medical tools, water buckets, hay feeders, etc.

The quarantine area must be easily cleanable with nonporous surfaces to prevent bacterial build-up. Delaney recommended using pine shavings or sawdust for bedding, as they are antimicrobial.

If the quarantine area is an outside space, properly disinfect it by removing the manure and allowing the surfaces to sit in the sunlight. If the quarantine area is an inside space, all the bedding and manure should be moved to a designated compost pile, the surfaces should be power washed with soap and water, dried completely, exposed to a disinfectant solution for the appropriate contact period and dried completely.

Choosing a disinfectant can be intimidating, as there’s many to choose from. Farmers should choose their disinfectant based on what they’re trying to kill, if it has any toxins or negative effects, how long the diluted solution lasts, the contact time required and the cost. Talk with your veterinarian to find recommendations, and take the time to read the product label.