Effect of High Level Inclusion of Adsorbent Materials in Litter on Chicken Welfare, Performance and Litter Ammonia Production

Excessive nitrogen volatilization from poultry litter as ammonia (NH₃) is harmful for chickens and poultry workers' health. Litter amendments such as bentonite and zeolite can reduce NH₃ and improve air quality in the poultry shed. Inclusion of these materials in poultry litter can reduce nitrogen volatilization and the solubility of phosphorus thus increasing the fertilizer value of the spent litter. To determine the extent to which the latter could be optimised we investigated the effect of high level inclusion of bentonite and zeolite in fresh pine shavings on broiler chicken live weight and welfare and a range of litter measurements including NH₃ production using the chamber acid trap method. The experiment ran for 42 days and had 5 treatments each replicated in two 2.25 m² pens with 25 chickens per pen. Treatments were nil amendment and 33% and 50% by weight addition of each of bentonite and zeolite. Inclusion of bentonite but not zeolite at these levels increased mortality of chickens during brooding, but did not adversely affect chicken live weight, footpad dermatitis, hock burn, breast blister and breast feathering of chickens up to day 42. Both amendments significantly reduced NH₃ in litter up to day 28. The effects of these amendments on the fertilizer value of the end of batch litter are under investigation.