It’s no exaggeration to say the very economic heart of the swine industry is the sow farm, because any successes or failures will flow all the way through the production chain to the final consumer. Managing sow health is critically important, especially considering such challenges as PRRS 1-4-4 L1C. One method of responding to disease that has been growing in popularity is herd closure, which allows for the elimination of the pathogen(s) or for the herd to stabilize and reduce the impact of future outbreaks through immunity. While your veterinarian is best suited to advise what method of disease management meets the needs of your farm, here are some economic considerations.
Accounting vs. Opportunity Costs
The cost of herd closure can be separated into two categories, accounting costs and implicit or opportunity costs. Accounting costs are costs you will find in your financial statements such as payroll, medication, etc. Opportunity costs are losses from missed
production potential, such as sow losses, litters aborted, preweaning mortality, etc. While it can be an arduous task, with the assistance of your vet and online resources, calculating the accounting costs of herd closure for your farm is straightforward.
What is a trickier process is estimating the opportunity costs of closure because those impacts are hidden among the effects of disease. To answer this question, we published a paper using farm data to separate the cost of closure from the cost of a Mycoplasma hyopneumoniae (M. hyo) outbreak.
Breeding Group Composition by Parity
We found the chief impact of herd closure is the disturbance to parity structure, which can be seen in Chart 1 where a “ripple” can be seen over time.
Average Parity Served
This leads to average parity increasing during closure and in the time shortly after, as shown in Chart 2. However, the farm where this study was conducted used closure as an opportunity to concentrate the previously erratic average parity around a younger and more productive average. This affected the number of pigs weaned, not through total piglets born, but in the number of piglets that died. While death loss caused by older sows can be mitigated through proactive management, labor availability might render this wishful thinking.
Net Sales & Dead Piglets
Chart 3 shows the number of dead piglets and how cumulative net sales change during the different periods. In the post-close period, the number of dead piglets continued to decline due to the improvements in parity structure.
Net Sales - Closure & M. hyo
Chart 4 shows the cost and time to baseline net sales of herd closure compared to the cost and time to baseline of M. hyo. This comparison shows the economic impact of closure is relatively insignificant compared to the cost of disease. Considering that in this case, and likely in many other cases, there is room to improve the parity structure. Meaning that not only are the losses from closure erased sooner but a new level of productivity can be achieved. This leads to the conclusion that when properly executed, herd closure is a cost-effective way to deal with outbreaks.
