A team from the Iowa State University College of Veterinary Medicine have begun a study examining manure pumping effects on disease onset in wean-to-finish pigs. The objective is to identify practices related to manure pumping that can be managed to decrease incidence of disease onset in pig populations, while identifying risk factors associated with disease onset in wean-to-finish sites following manure pumping and spread.
The preliminary analysis, released in September, was based on a total of 3,000 pumping events across 594 wean-to-finish sites and 1,358 pig lots. A median of two pumping events per pig lot was observed. The pig mortality rate in the two weeks following the first pumping event was 21.3 percent lower in sites that transported manure using tanks compared to sites using drag hoses. No statistical difference in mortality was observed between sites that applied manure to surrounding fields using either direct injection or airway. Likewise, no statistical difference was observed in mortality between sites that included manure storage in deep pits versus lagoons or concrete vats.
The preliminary analysis found that using tanks to transport manure to crop fields that are farther away from the pumped site was associated with a lower mortality in the two weeks following the first pumping event when compared to drag hose. These results demonstrated an association between the distance at which manure was applied and disease onset and mortality rates after pumping events.
The next step for the ongoing study will be modeling that includes sites with and without disease onset, and with and without exposure to pumping.