Dietary strategies to reduce air emissions from laying hen operations

Abstract

The objectives of the current study were to evaluate the effectiveness of feeding a reduced emission diet (R) containing 6.9% of a gypsum-zeolite mixture and slightly reduced crude protein (CP) to 21-, 38-, and 59wk old Hy-line W36 hens (trials 1, 2, and 3, respectively) on egg production and emissions of NH3, H2S, NO, N02, C02, CH4 and non-methane total hydrocarbon (NMTHC) as compared to feeding a commercial diet (C). At each age, 640 hens (BW = 1.36, 1.47, and 1.52 kg in trials 1, 2, and 3, respectively) were randomly allocated to eight environmental chambers for a 3-wk period. On an analyzed basis, the C diet contained 18.0, 17.0, and 16.2% CP and 0.25, 0.20, and 0.20% S in trials 1, 2, and 3 and the R diet contained 17.0, 15.5, and 15.6% CP and 0.99, 1.20, and 1.10% S in trials 1, 2, and 3. Diets were formulated to contain similar calcium and phosphorus contents. Average daily egg weight (ADEW; 56.3 g), average daily egg production (ADEP; 81%), average daily feed intake (ADFI; 92.4 g) and BW change (BWC; 23.5 g), across ages, were unaffected by diet (P > 0.05). Age effects were observed for all performance variables (P 0.05) were