Biosecurity is a combination of management practices designed to prevent the introduction and transmission of diseases and disease-causing agents into a herd. Prevention of the entry of diseases into a herd is a key component of a herd health management plan. Procedures that are typically associated with a biosecurity plan include barn and transportation sanitation, rodent control, worker and visitor entry policies and other general farm security measures. If a disease is already present in one or more segments of the herd, biosecurity can help prevent that disease from spreading to other segments. However, all biosecurity measures should be focused on the prevention of the entry of disease.
Knowing how pig diseases can come into a herd (directly and indirectly) and how they are spread can assist in the development of a biosecurity plan for the herd. Pigs are susceptible to many different diseases. Diseases are caused by pathogens, which can be bacterial, viral or parasitic. Common diseases of pigs can spread or transmit in multiple ways. When pigs from different farms are brought to another farm or area and are commingled with other pigs with a different health status, the risk of catching a disease can be high. Therefore, a biosecurity plan should take into account how diseases are transmitted and try to minimize exposure as much as possible.
Organisms that cause disease in pigs, such as bacteria, viruses and parasites, can survive in a range of materials, so they can easily hitch a ride and spread disease. Organic matter (shavings, manure), feed, water, mud and snow can all transfer diseases from site to site.
While we don’t have all the answers, research has already told us much about the risk of cross-contamination through transport practices. Contaminated boots, clothing, tires, undercarriages, trailers, shovels, sorting panels and people’s clothes are all potential risks.
Applying a line of separation and other farm biosecurity steps that address cleanliness will go a long way in offering protection during transport activities. Other activities, such as walking into a contaminated barn or packing plant, can increase disease risk because boots and trailers can become contaminated.
Other steps to take include designating a trailer to transport specific pig groups, such as one for weaned pigs and another for market hogs.
If finished hogs are transported to market through a service, make sure the collection moves from the highest to lowest health-status sites. Invest in a truck-wash facility or gain access to one.
To clean trailers, the priorities are to scrape out all organic matter, wash, disinfect, dry (heat if possible) and allow downtime between pig shipments. Overall, design pig flow to reduce cross contamination.
The Pork Checkoff’s Transport Quality Assurance (TQA) program offers many resources for swine transporters, producers and handlers to better understand best practices for transporting pigs to ensure animal safety and ultimately, food safety.
Using lines of separation
If a ‘line of separation’ isn’t created and maintained on a farm, biosecurity has not been achieved. Several lines may need to be set up within a site, because biosecurity is not just about exposure from the outside, but also the lateral spread of disease.
At its most basic, a line of separation designates the outside (contaminated) area and the inside (clean) area. Think in terms of drawing a line in the sand – a point at which certain parties must not cross.
For example, a line should be identified where the animal transporter is not to cross and where farm or market personnel are to remain. If a barn worker does cross it, they cannot return to the clean side. The separation line must be clearly marked, with individuals made aware of where it exists in every situation.
Lines of separation for transporters might be at the cab of a truck, the back of a trailer or a loading chute. Within a production site, the shower or bench entry would be the ‘dirty’ side, while the shower exit would represent the clean line. Another line could be a designated driveway that feed trucks must use to control traffic flow and potential exposure.
Control of wildlife, rodents and pests
Wildlife, birds, rodents, feral swine and other pests can readily transmit many diseases and compromise biosecurity. Limiting exposure to these animals will protect pig health. Basic practices should be in place to prevent unwanted animals from entering facilities like fencing or netting off protected areas, removing sources of food that can attract populations, implementing sterile zones and appropriately disposing of mortalities when necessary.
Sanitation on the farm
Proper sanitation of the facility and equipment means keeping it free of dirt and debris as much as possible. Organisms that cause disease in pigs can survive in different types of materials. Cleaning, disinfection and drying of facilities is a critical part of daily sanitation and a key component of a biosecurity plan that can keep the level of disease-causing pathogens to a minimum.