Reducing Diet Digestibility and Increasing Pen Cleaning Frequency: Effects on Nitrogen Losses and Compost Nitrogen Recovery

A finishing trial evaluated effects of diet and management on N losses from open feedlots and compost N recovery. Steer calves were fed in 12 pens from November to May. Nitrogen losses from pens were compared by feeding corn bran (30% diet DM) designed to increase OM excretion and by increasing pen cleaning frequency in a 2 x 2 factorial design. Pens were either cleaned monthly or once at the end of the feeding period. Corn bran negatively affected feed/gain by 8.1% and reduced ADG by 4.4%. Dietary treatment and pen cleaning frequency interacted for N balance in the feedlot. Nitrogen losses from pens decreased and manure N increased for steers fed corn bran if pens were cleaned monthly. Corn bran increased the amount of N remaining in composted manure regardless of cleaning frequency. Feeding corn bran and increasing pen cleaning frequency will reduce N losses from open feedlot pens and increase N recovery in compost