Staging of swine carcasses to mitigate leachate contamination in the environment.

Abstract

Outbreaks of infectious diseases involving depopulation of animals require on-farm practices to stage carcasses when final disposal methods are unavailable. The current study assessed various materials and techniques for containing carcasses to minimize leachate and biological substances. The tested materials included tarps, soil, corn stover (CS), and lime, while the methods involved covers, chemical additives, barriers, and containment. Treatments included the following: 1) control, carcasses in a pile; 2) carcasses wrapped in tarp material; 3) carcasses covered with tarp material; 4) carcasses covered by soil; 5) carcasses placed on CS base with tarp cover; 6) carcasses on CS base with CS covering; and 7) carcasses on CS base with a lime covering. Each treatment was run in triplicate using three carcasses per replicate. Temperatures, headspace gas, and leachate from carcasses were collected over a 91-day holding period. Pairwise comparisons of means were made when treatments were significantly different. Carcasses lost significant amounts of their liquid contents in the first 27 days. Leachate contents were initially filled with organic material and potassium that significantly declined with time, while Fe, Zn, and Cu concentrations increased significantly over time. Covers did not reduce leachate volume, but soil covers significantly reduced substances in the leachate. Corn stover barriers significantly reduced both leachate volume and substances in the leachate. Containing carcasses in tarp material was the most effective method for holding leachate and preventing its loss to the environment. This research demonstrates that growers should focus on sealing carcass containers and constructing barriers to limit surface contamination during depopulation events.