Antibiotic losses in runoff and drainage from manure-applied fields

The objective of this research is to quantify the effects of liquid swine manure application on antibiotic and nutrient (N and P) losses via surface runoff and subsurface drainage under a conventional (moldboard plowing) and a conservation (chisel plowing) tillage system. The field experiment is set up at the University of Minnesota Southwest Research and Outreach Center, Lamberton, Minnesota. The soil at the experimental site is a Webster clay loam soil (fine-loamy, mixed mesic Typic Haplaquoll), a common soil series in the Minnesota River Basin. The experiment is a randomized split-plot design with four replications (Figure 1). The main plots consist of two tillage treatments: (1) fall moldboard plowing followed by two passes of field cultivation before corn planting; and (2) chisel