Laboratory evaluation of ensiled poultry litter

Poultry litter collected from a commercial broiler house, bedded with wood shavings, was used. The material was screened and ground before it was ensiled either alone or with other agricultural by-products, namely chopped barley straw, a mixture of weeds and grapefruit peels. The digestible organic matter in the dry matter value in vitro (0·39) for litter was comparable with that for straw and weeds. Of the total nitrogen (36·3 g/kg dry matter), 0·19 was ammonia-nitrogen and 0·77 protein-nitrogen. Digestible energy and crude fibre in the litter were 7·19 MJ and 334 g/kg dry matter, respectively. Addition of poultry litter at ensiling resulted in significant increases in nitrogen and ash content of the original mixtures. Inclusion of sodium hydroxide in fermented and non-fermented mixtures elevated digestible organic matter in the dry matter values in vitro by 0·19 and 0·13, respectively; the crude fibre concentration was lowered. All initial mixtures were free of lactic acid and were positive for the pathogen Proteus when tested. Unlike crude fibre, fatty acid and free ammonia, which were increased after fermentation, digestible organic matter in the dry matter and pH values were decreased. Ensiling killed the pathogen Proteus in the majority of the silages tested. The silages had a pleasant aroma and colour, and were consumed by Chios sheep.