Everyone from animal producers through consumers of animal products have a vested interest in promoting sound biosecurity practices on farms. Visitors and agricultural service personnel should be proactive and ensure that their actions do not jeopardize the health and safety of the farms they visit. Although fairs and animal exhibitions are important venues for educating the public regarding livestock, animals that return to a farm after a show, or that come from a sales/auction arena, could easily be a source of infectious agents.
How is biosecurity risk recognized?
Assessing the risk of introducing and transmitting infectious disease in animal agriculture systems is complex. Factors such as the existing prevalence of the pathogen (infectious organism) in the general population and in the herd, the number and location of susceptible animals, and likelihood that new infections will be established must be evaluated. Disease risk classification is based on such diverse factors as pathogen virulence, environment, geographic distribution, economic impact, population dynamics, different animal species interactions, and susceptibility of individuals, strains, or lines. Animal disease organisms are often categorized into four risk groups, based on their existing prevalence and likelihood for spread:
- Organism is usually enzootic*, and only cause mild disease. Unlikely to spread significantly or rapidly. Official control programs rarely implemented.
- Organism is usually enzootic. Infection may result in no more than moderate disease, with limited spread. These pathogens may or may not be the target of an official control program.
- Organism may be enzootic or exotic**, which may spread rapidly. Infection usually results in serious disease. Official control programs are frequently in place.
- Organism is usually/frequently exotic. Infection usually results in severe disease, and spreads very rapidly. Treatment and prevention are difficult or not effective. Strict control programs usually in place.
Domestic animal diseases that are of the most concern under normal circumstances are those in levels 2 and 3.
* always present at some level in at least some herds/flocks/wildlife in the population
** foreign animal or trans-border disease - not currently present in US herds/flocks/wildlife
What are the likely causes for disease spread?
Animals, animal products, and/or animal secretions (including manure and urine) most often spread infectious diseases between animals or herds. New animals entering a herd or flock, or direct contact with infected animals, are the most likely ways to introduce disease to an uninfected herd. Therefore, biosecurity programs should always include a strict risk assessment of herd additions or contact with animals. Animals returning from exhibitions or contact between people and animals at exhibitions can also be a biosecurity concern. People can transport infectious diseases on their clothes and on occasion on their skin or mucous membranes. Ag service personnel can also present biosecurity concerns if equipment or products are carried from farm to farm without proper precautions.
How can I tell if I am a risk or if my herd is at risk?
Several risk assessment forms have been developed that allow individuals to judge how risky actions and practices may be for spreading organisms of concern. Extension veterinarians are encouraging livestock producers and the public to take biosecurity seriously and help keep our herds and flocks safer, reduce animal suffering, help to continue to increase the quality of animal agriculture products, and improve the sustainability as well as the profitability of our farms. An example of a risk assessment form is shown below. For additional information on biosecurity or conducting a risk assessment please contact any of the extension veterinarians listed below.
Table 1. Visitors to a Farm (Veterinarians, Ag Service Personnel, Visitors and Neighbors)
|Risk Concern||Low Risk||Moderate Risk||High Risk|
|Number of farm visits per day||One farm, little or no animal contact.||Occasionally visits more than one farm per day. Minimal animal contact.||Visits many farms or auctions. Significant animal contact.|
|Protective clothing||Wears clean & sanitized shoes or boots. One pair of coveralls per site.||Wears sanitized boots and clean coveralls. If clean may not change coveralls.||Does not wear protective clothing, or uses the same clothing between farms.|
|Leaves materials or borrows supplies||Materials and supplies away from animal or feed areas.||Materials and supplies in areas of minimal animal or feed contact areas.||Materials and supplies may be left in animal or feed contact areas.|
|Animal ownership||Does not own similar species at home.||Similar species but a different production type.||Owns and/or cares for a similar species and production type at home.|
|Contact with potentially infected animals||Minimal or no contact with potentially infected animals.||Contact with healthy animals and avoids contact with potentially infected animals.||May own or be exposed to many animals of unknown health status.|
|Work in animal contact areas||Does not work in areas with highly susceptible animals.||Minimal exposure to high risk animals and only with protective clothing.||Works with highly susceptible animals. Little precautions.|
|Biosecurity knowledge||Understands and promotes biosecurity for industry.||Aware of biosecurity principles but is not an advocate.||Little appreciation for biosecurity and does not view it as an industry issue.|
|Foreign Travel||Does not travel out of the US or Canada.||Limited travel outside of US or Canada without animal contact.||Travel to foreign countries with animal contact in those countries.|
|Foreign Visitors||Prohibits foreign visitor contact with animals or feeds.||Foreign visitors may be in animal or feed areas after adequate quarantine.||Visitors are permitted in animal or feed contact areas without screening or quarantine.|
Table 2. Other Animals - Livestock Exhibitions and Purchased Animals
|Risk Concern||Low Risk||Moderate Risk||High Risk|
|Purchased animals||Screening tests and quarantine for 30+ days after purchase.||Minimal screening; quarantine for only 15-30 days.||No screening; no quarantine or <15 days.|
|Protective outer clothing||Clothing and boots worn on home farm and not worn to different farms or animal events.||Clean clothing and disposable boots or sanitized boots.||Clothing or boots worn on home farm and also worn to different animal events.|
|Immunizations||Timely, comprehensive plan coordinated with veterinarian.||Immunization based on show regulations but not necessarily part of total plan.||Haphazard immunization plan that is not coordinated nor professionally supervised.|
|Animal transportation||Haul own animals only in your trailer or truck.||Haul animals in another's truck or trailer that has been cleaned or sanitized.||Haul animals in another's truck or trailer without sanitation.|
|Equipment at exhibition or sale||Only use grooming, feeding or watering equipment for your animals.||Clean equipment before sharing.||Equipment shared without cleaning or sanitation.|
|Contact of public with animals||Prohibit people from petting and feeding of your animals.||Allow petting but discourage people from feeding your animals.||Allow public to pet and/or feed animals.|
|Isolation after exhibition||Isolate for 15 days after exhibition.||Isolate for >7 days but <15 days after exhibition.||Isolate for <7 days after exhibition.|
Prepared by Drs. Ernest Hovingh, Bhushan Jayarao, Robert Van Saun, David Wolfgang and Lawrence Hutchinson; Veterinary Extension & Applied Reserach Team, Department of Veterinary & Biomedical Sciences..