The effect of processing method of broiler litter on pasteurization, nitrogen loss and nitrogen utilization by sheep

Various broiler litter processing methods were evaluated. Treatments effective for litter pasteurization were dry heating at a depth of 0.63 cm for 20 min; autoclaving for 10 min. or longer; dry heating following the addition of 1 to 4 g of paraformaldehyde (PFA) per 100 g of litter at depths of 0.63 and 2.54 cm; and ethylene oxide (ETO) fumigation for 30 min. or longer. Moisture and uric acid nitrogen were lowered (P < .01) for dry heat and the PFA processes. Autoclaving and PFA addition followed by dry heating lowered (P < .01) NPN. Ammonia nitrogen was reduced (P < .01) by all pasteurizing treatments except autoclaving for 10 min. A metabolism trial was conducted with sheep. Litter pasteurized by dry heating at a depth of 0.63 cm for 20 min., dry heating at a depth of 2.54 cm after the addition of 2 g of PFA per 100 g of litter or fumigation with ETO at a depth of 15.24 cm for 60 min. supplied 50% of the nitrogen in the respective rations. Processing method had no significant effect on nitrogen utilization and apparent digestion coefficients. Ruminal ammonia nitrogen was higher (P < .05) for the dry heat than for the ETO treatment. Acetic acid and total VFA's, expressed as µ mole/ml were higher (P < .05) for the PFA than the dry heat treatment. Expressed as moles/100 moles, propionic was higher (P < .05) for the ETO than for the PFA treatment.