Effects of distillers dried grains with solubles and mineral sources on gaseous emissions

Distillers dried grains with solubles (DDGS), an important ethanol industry co-product, has been used as a high-protein feed in poultry production. Limited studies exist on their effect on air emissions, however. In the current study, 4 diets (2 × 2 factorial design: 0 or 20% DDGS + inorganic or organic mineral sources) were fed to Hy-line W36 hens from 50 to 53 wk of age and the effects of DDGS level and mineral sources on air emissions were monitored continuously for a 23-d period in environmentally controlled chambers. The NH₃, H₂ S, CH₄, nonmethane hydrocarbons, N₂ O, CO₂, and CO₂-equivalent emissions ranged from 0.51 to 0.64 g/day-hen, 0.71 to 0.84 mg/day-hen, 33.9 to 46.0 mg/day-hen, 54.1 to 60.0 mg/day-hen, 66.0 g to 72.2 g/day-hen, and 83.1 to 92.1 g/day-hen, respectively. Feeding DDGS to laying hens resulted in 14% decreased NH₃ emissions but a 19% increase in CH₄ emissions without affecting other gaseous emissions. More than 30% of N, 80% of P, 80% of K, and 50% of Ca was retained in the manure. In conclusion, feeding laying hens a diet containing 20% DDGS may be beneficial for the environment. Substitution for organic trace minerals did not affect hen performance or air emissions.