Those of us in the midst of an animal-health fire understand that things don’t always unfold as we plan. But if we’re honest, we also will admit that sometimes things go right in spite of our plan.
As a swine practitioner, it can be an easy move to recommend changes to the management of a group of pigs in a barn, to an entire farm or to a production system. After all, someone else (or many someones) is faced with carrying out the marching orders. But unless I have an understanding for the lay of the land any given suggestion that I give may be doomed to fail. It may be right for the pig but it won’t work for the people, or it may be too expensive to implement or take too long before it can be completed.
For example, a medicine’s pre-slaughter withdrawal may not fit the system’s pig flow, or I might hear “Doc, we couldn’t start it when you suggested because the feed bins were full.”
Two questions I always try to ask myself: Did I accurately provide options, and is the plan we agreed on simple enough to get done right?
The primary swine disease on our radar screen and in our pig herds during the past 20 years has been porcine reproductive and respiratory syndrome. While other disease agents are economically important to the
Much has been learned about the virus, such as how both cell mediated immunity and serum neutralizing antibody appear to have important roles in protecting against subsequent exposure to PRRS virus, and that immunity takes a relatively long time to develop as compared to other disease agents. Also, natural movement of PRRS virus in a PRRS-naïve pig population can be prolonged or incomplete. This results in subpopulations and extended clinical signs and costs for the herd.
Certainly, we still have a long way to go.
So, how does one approach the almost universal problem of PRRS virus?
Simply put, population management has two fronts:
Keeping disease out of a herd.
Deactivating the disease.
The tools available to prevent the disease from entering a farm include:
Site location or geography.
Pig flow – sourcing rules.
Facility barriers – defined dirty/clean lines at entries, bird screens, rodent control and air filtration.
Transportation controls – flow-dedicated trailers and wash/dry protocols.
Many of these and other measures have been adopted across our industry with success, especially when it is easy to do things right. Multi-site production, while largely beneficial due to labor specialization, access to capital and more accurate group records, has worked against health when pigs from multiple flows commingle in the same barn, site or neighborhoods.
Regional PRRS eradication efforts require a high level of cooperation among the area’s producers.
Efforts within the industry have begun on a voluntary basis. The Internet and global-positioning systems are new tools that allow accurate and timely pig-flow and site-health information to be more readily shared among neighbors today.
So, have you started doing the right things?
The process of deactivating disease involves applying additional tools. Some may be purchased — such as antimicrobials, disinfectants and vaccine. Others rely on the use of biological material from the resident population — seeder animals, feces, tissue or blood that includes the infectious causative agent.
While there is conflicting data from research, farms and veterinarians about the best methodology for stabilizing PRRS-positive herds, PRRS-negative flows of pigs can be consistently established from positive sow farms. But many farms have successfully eradicated PRRS virus from their pig populations only to become re-infected with the same or a new isolate.
With the advent of genetic sequencing, it is possible to track the movement of PRRS virus in a production system or within a geographic neighborhood. PRRS virus transmission via direct contact of pigs or pig materials such as feces, urine, saliva and blood; contaminated fomites; and air have been documented. It will take everything in the current toolbox plus new developments and cooperation among people to eliminate PRRS from the
However, our battles aren’t just with domestic disease, especially in the long run. For instance, in spite of many concerned comments from the pork industry, veterinarians, animal-welfare activists and health commissions, USDA’s Animal and Plant Health Inspection Service has amended its regulations “to allow for the importation of uncooked pork and pork products from regions where classical swine fever is considered to exist if the uncooked pork and pork products originate in a region free of CSF and that meets certain other conditions with respect to processing and shipping.” (Federal Register, Vol. 73, No. 64,
What does this mean for
In terms of herd health, it surely is not an example of doing the right thing or of doing things right.