Fall is the time when us pig veterinarians start getting nervous to answer phone calls from our farmers. The shorter days mean different things for veterinarians and farmers, but it’s an equally busy time of year. For farmers, autumn means harvesting the crops and spreading manure. For veterinarians, it’s an awful-tasting pumpkin spice latte full of PRRS virus, PED virus, and others including influenza. We commonly refer to September as the beginning of PRRS and flu season, but viruses (and bacteria) alike prefer colder weather and wet conditions. The colder seasons also pose an interesting paradox of increased disease pressure with decreased time actually looking at the pigs. Every vet has a name for this condition, but I refer to it as corn harvesting disease. With more time spent in the fields, pigs still receive daily care, feed, water, and observations, but attention to detail can slip. When all of this is combined with the looming threat of foreign animal disease, now is the time to review some basic biosecurity steps that work.
If you ask four swine veterinarians for their definitions of biosecurity, you’ll likely get a minimum of five different answers. They’ll all boil down to a common thread, but biosecurity, like other concepts left up to veterinarians, can get incredibly complex and confusing. For reference, my favorite nerdy explanation of the term further breaks it down into three practices: biomanagement, biocontainment, and bioexclusion, but I digress. Biosecurity, at its core, is simply the practices we use to keep diseases out of our herds. Having a background in a genetics company, I’ve seen and heard of some pretty crazy tactics used to keep diseases out. I’ve legitimately taken three showers to get into one farm! I’ve also heard from my colleagues about being “spray-disinfected” without their clothes on while walking through a maze-like structure that prevents going too quickly. What we’ve learned from these experiences is these off-the-wall tactics don’t work any better than basic practices, but instead it comes down to integrity and trust. At the end of the day, none of these practices work if we don’t employ them every time. Biosecurity must be a mindset and a lifestyle, because one deterrence from the rules can cost thousands or even millions. So, if biosecurity must be ingrained and adhered to, and we also need to trust all employees on farms to do the right thing when no one is watching, we must set some basic principles that are easy to follow.
- Downtime is your friend: In my previous life, we referred to health on farms as dynamic. Knowing health statuses of farms (and recognizing they can change overnight) is important to keeping all farms healthy. The basic rule of thumb is to always start at the highest health status farm and work down the line in order of health. In our system, we typically quantify time away from pigs in “nights”. Going from an unhealthy site back to a healthy one should require downtime of a minimum number of nights. Systems will vary on these requirements, but downtime is a core biosecurity concept.
- Danish entries are necessary: A true Danish entry includes a bench for changing shoes (and keeping street shoes off common walkways inside the farm), clothing change, and washing of the hands (and in some instances also the face). The key is limiting the cross-contamination of anything between populations of pigs.
- On that note, wash your truck: Inside and out, as often as you can!
- You can’t disinfect a turd, but disinfectants work: Clean is a relative term, but for biosecurity purposes, cleanliness is next to godliness. Barns, trucks, trailers, and any area that pigs interact with should be thoroughly and completely washed between groups of pigs AND disinfected. There are many disinfectants that work but your veterinarian likely has a favorite to recommend.
- Establish a clean/dirty line: The clean/dirty line (CDL) should be established for every threshold on a site. The bench is the employee CDL, but there should be one for loadouts, mortality management areas, and any other entry/exit for the barn. Follow this line every time. If you ever played the game “the floor is lava” as a kid, treat this CDL as seriously as your imagination treated those expanses of space between the pillow safe zones.
In the end, biosecurity is a mindset. It must be integral, and it must be done with integrity. It must be easy enough to follow that breaking the rules seems ludicrous. In short, wash your truck, take the night off, wash your face, change your clothes, and let your childhood imagination treat these invisible diseases like the lava on your living room floor.