Health and environmental implications of using composted household and yard waste bedding in a cattle feedlot

A study was conducted to determine the safety and feasibility of using muni cipal solid waste compost (MSWC) as a bedding material for cattle feedlots. Two pens in an open-front pole barn were bedded with either corn stalks or MSWC in each of two feeding periods (blocks) with two pens (23 x 34 m) per block. Block 1 used 336 heifers (initial BW, 398 kg) during a 104-d period (summer), and Block 2 used 276 steers (initial BW, 412 kg) during a 92-d p eriod (winter). Blood concentrations of regulated elements (Cd, Cu, Mo, Pb, Ni, and Zn), electrolytes, glucose, or liver and kidney enzymes were unaff ected (P > .05) by use of either bedding material. Polychlorinated biphenyl s in perirenal fat were not detectable (< .5 ppm) in cattle bedded with eit her material. At slaughter, kidney Cu and kidney and liver Pb concentration s were greater (P < .05) for cattle bedded with MSWC. Despite this, tissue concentrations of these elements were well within those considered normal f or healthy cattle. Regulated element concentrations of feed did not differ (P > .05) between diets within period, and neither did DMI or DM digestibil ity; therefore, cattle bedded with MSWC were likely inhaling additional amo unts of these elements and excreting them through feces. More MSWC than cor n stalks was required to supply a dry bed per animal daily (P < .05). Soile d bedding (manure as-is) output was similar (P > .05) for both bedding mate rials. On a DM basis, more manure (P < .05) was removed from the pen bedded with MSWC in Block 2. Total manure N and P removed was similar for both be dding materials. Nitrogen and P concentrations in manure were lower (P < .0 5) during Block 2, but total manure N removed was greater (P < .05) during Block 2. Total manure P removed from the pens was not affected by season. U nder the conditions of this study, MSWC seemed to be a safe and effective b edding material for cattle feedlots.