Time for a Biosecurity Tune Up
Implementing and reviewing some of the procedures discussed by Elizabeth Ferry, Extension Educator, Cassopolis, Cass CO, in the MSU Pork Quarterly will put you on the right track for producing high-health pigs and the proper utilisation of biosecurity protocols.High feed costs, animal welfare concerns and environmental matters are all issues struggling to take top priority with today’s pork producers. High on that list of priorities in the winter months must also be a review of biosecurity protocols for individual facilities and production flows. Biosecurity can be defined as procedures, efforts and programmes established to reduce the risk of disease introduction in to pig populations (Conner, 2001). Both external and internal biosecurity protocols need to be reviewed for their effectiveness in keeping out new agents and minimising the disease challenge present within a barn or herd.
Biosecurity and sanitation practices are implemented on many pork production units to prevent the introduction of pathogens to the herd or groups of pigs within a herd (Amass, 2001). A disease challenge such as Salmonella, influenza, Mycoplasma and porcine reproductive and respiratory syndrome (PRRS) not only affects the health and productivity of the herd, it also diminishes employee satisfaction with their job and decreases the profit margin for the producer. PRRS is an economically significant disease that has been estimated to cost the US pork industry approximately $560 million a year (Dee, 2010). Preventing and controlling the spread of diseases such as PRRS, within and between pig populations is critical to the success of producing high health pigs and is the basis of biosecurity programmes.
Biosecurity is a complex concept compiled of various protocols, theories and management procedures. Implementing and reviewing some of the procedures discussed below will put you on the right track for producing high-health pigs and proper utilisation of biosecurity protocols. As you evaluate your biosecurity programme for effectiveness and impact, you need to look at both direct and indirect routes of contamination.
Direct routes of contamination include live animals and genetic material (i.e. semen) and are large factors when it comes to controlling the spread of disease. Purchasing your semen and replacement stock from verified sources that are monitored via testing protocols is necessary when protecting the health of your herd. The procured animals must be transported in a clean and disinfected vehicle and loaded and unloaded properly using clean and disinfected load areas (Tubbs, 2001).
When introducing new animals into the herd, an isolation period is critical to evaluate the health status of the animals. Isolation should occur in facilities separate from the production site and located a minimum of 120 metres (approximately 130 yards) from the breeding herd (Dee, 2010). Animals should stay in isolation for a period of at least 30 days and assessed daily for clinical signs of disease. Management of isolation facilities should take place following completion of all duties at the breeding or parent site; employees responsible for duties in the isolation unit should shower out after checking the unit and not return to the breeding/parent herd until the following day.
Replacement stock should be blood tested 24 to 48 hours after arrival to the isolation facility as well as five to seven days prior to entry into the breeding unit (Dee, 2010). Implementing these isolation techniques and testing protocols will aid you in protecting your herd from the introduction of new disease agents and maintain the current health level of your herd.
Another area to evaluating the biosecurity at your facility is to look at the indirect routes of contamination. Indirect routes of contamination are methods of transmitting disease mechanically through; people, vehicles, facilities and non-human vectors such as, needles and supplies. Controlling all aspects of indirect contamination on farms is one of the biggest challenges in pork production. Not only must you identify and utilise biosecurity protocols that work for your facility, you must train employees and service people to strictly follow the guidelines that you have set in place. Consistent evaluation and audits of these guidelines are required to keep your facility and employees functioning at a higher level of biosecurity awareness.
In order to maintain a high level of biosecurity at your facility, you should apply an all in/all out management system to your pig flow, reducing the flow of disease from older pigs to younger more naïve animals. All in/all out (AI/AO) standard operating procedures allow you to group pigs according to age and empty or fill entire rooms at once. When working with piglets, if your site is involved in a disease outbreak it is important to move as few piglets between litters as possible, reducing cross-fostering of litters and decreasing the spread of disease.
In order to maximise the benefits of Al/AO protocols, it is extremely important to wash, disinfect and dry your facility between groups of pigs.
When auditing your sanitation procedures on the farm you should prioritise the following protocols with employees: Completely remove all organic material from area and power-wash all surfaces, extra attention should be given areas that are hard to reach and may harbor organic matter. Once the area is surface clean, a disinfectant should be applied to the area. Commercial disinfectants need to be researched so that the product is effective on diseases specific to your facility. The application of disinfectants via a foamer allows for better visualisation of where product has been applied and also prolongs the contact between the chemical and surface areas (Dee, 2010). Once the washing and disinfection procedures have taken place, it is important to allow the area sufficient time to dry. This single step is critical when controlling disease, as inactivation of a virus is directly related to length of drying time.
Another potential source of indirect contamination can be found in fomites. Fomites are non-human vectors such as needles, coveralls, supplies and containers that can transport and spread disease. Needles can be contaminated by injecting an animal that is infected with a virus, continued use of the same needle between animal’s results in the spread of the disease. If your farm is experiencing a disease outbreak, needle use protocols should be examined. Options of changing needles frequently or implementing a needle-free injection process can be used to reduce this risk; however, these practices are not guaranteed to completely eliminate the spread of a virus. Boots and coveralls are also vectors that transfer disease, washing coveralls and boots after daily use are minimal biosecurity protocols that should be implemented on the farm.
As we review our risk of contamination via fomites, we need to look at the delivery of supplies and items that may be brought into the farm by vendors. A way to reduce the instance of disease transfer on these types of fomites (supply boxes, bags and tools) is to incorporate a disinfection and drying (D&D) room on your facilities. A D&D room is an area where supplies or contractor tools are received for biosecurity processing before they enter the farm. These rooms are the only entry method for supplies and tools and need to follow strict protocols. In these locations, an employee will apply disinfectant to the entire supply container or tool, covering every side with a foaming disinfectant. It is very important to apply the disinfectant with a foaming applicator verses fogging the room, as the direct contact of the foam will work to kill any live virus that might be travelling on the outside of the container. A D&D room may not be an option for all facilities and the ‘double bagging’ method of transferring supplies can also reduce the risk of disease spread. This practice requires all supplies or tools entering the farm to be placed in a double-bag, once the items have reached the farm, the outer bag is removed and the items can be brought into the facility.
Personnel that work at swine facilities are also at risk of spreading disease. Although people are typically not a carrier of disease, as most organisms do not live in the human membranes, they can carry the disease on their person or clothing to different areas of the farm. When the swine facility is equipped with a shower, all employees should follow a shower in/out protocol every time they enter and exit the facility. If this option is not available for the facility, employees, at a minimum should wash their hands and change clothes, coveralls and boots between visits to different sites. Down-time of one night for personnel that have come in contact with pigs at another site or pigs with a different level of herd health is recommended. In order to limit access to a facility, all exit doors should be equipped with a locking mechanism and utilised at all times. Keeping the doors locked is a simple way to restrict movement (Lambert, 2009).
Biosecurity risks should be evaluated and prioritised for each facility and production flow. This first step will help producers develop practical, effective biosecurity protocols, while remaining in line with the cost of production for their individual production scheme. A continuous review and training programme should be implemented for all farm employees and vendors in order to make a biosecurity plan function in the manner that it was designed. Spot checks on employees and vendors, along with correcting deficiencies, will help maintain biosecurity efforts. Biosecurity practices and reviews of on-farm application will go a long way to help you protect the health of your swine herd. Stopping disease at the door of the farm will enable you to maintain your health status and continue to produce healthy pigs.
January 2012