Biosecurity is a series of management procedures designed to prevent or greatly reduce the risk of introducing new infectious agents to a farm. A related concept is biocontainment, management strategies directed at reducing the risk of spreading existing infectious agents between groups of animals or into the environment.  Key components to both concepts include: screening and testing, isolation and quarantine, immunization, selective purchasing and monitoring and evaluating.

Biosecurity is a whole farm approach to herd health management. The risks to herd health must be assessed, prioritized, and addressed. Risk can be categorized by source of possible infection, area of the farm or by susceptibility of animals.

(Definitions & concepts from Dr. John Thompson, AABP'96)

Risks To Consider

  • 1. Animal Density/Stocking Rate - Crowding of animals increases opportunities for aerosol and contact transmission. Crowded conditions also increases stress levels, affecting immune responses negatively. This is situation is particularly critical for animals housed within barns or other enclosed environments.
  • Avoid overstocking, provide adequate air circulation.

  • 2. Introduction of sick or unknown status animals to the herd - Risk can be introduction of a disease the herd has not been exposed to (naïve population)

  • 3. Shared water/feeding sites- Common feeding sites or water sources can be contaminated by infected animals. Animals that drink or eat from a common site then run the risk of becoming infected as well.

  • 4. Mixing of species – Some diseases can affect more than one species. In one species the diseases may have little to no health impact but by interacting with another susceptible species can result in devastating disease.

  • 5. Visitors- Domestic and international visitors can be a risk as they can be mechanical as well as biologic vectors (Mechanical: They can carry organisms on their clothing, shoes and even skin. Biologic: Some organisms can infect both people and animals meaning an infected person can be the source of disease for your animals.)

  • 6. Vehicles- Vehicles can serve as mechanical vectors of organisms and therefore can be a source of transmission across farms and even within farms.

  • 7. Health Monitoring/treatment- Undetected, untreated illnesses can put the rest of your animals at risk.

  • 8. Preventive measures (vaccines) – There are a variety of vaccines available that can assist in enhancing immune status. There are not vaccines available for all diseases.It should be noted that some vaccines do not prevent disease but decrease the impact.

  • 9. Animal handling/treatment practices- How you manage and treat animals can impact  the health of your herd or flock positively or negatively.

  • 10. Engage your local veterinarian when developing a biosecurity plan.

Biosecurity Information By Species

Contact Us

CDFA Animal Health and Food Safety Services,
Animal Health Branch

1220 N Street
Sacramento, California 95814
Phone: 916-900-5002
Fax: 916-900-5333
Our offices are open 8:00 AM to 5:00 PM Pacific Time.