Effect of soybean hull supplementation to finishing pigs on the emission of noxious gases from slurry.

Ninety six pigs were assigned on the basis of body weight (BW) to one of four dietary treatments (4 pigs per pen and 6 pens per treatment) and fed for 4 weeks. Four 14.85% CP diets were formulated to contain graded levels of soybean hulls at 0, 5, 10, or 15%, respectively. The results showed that treatments did not affect growth performance. Coefficient of total tract apparent digestibility (CTTAD) for dry matter (DM) and blood urea nitrogen (BUN) concentrations were decreased linearly (P < 0.05) with the addition level of soybean hulls. Slurry ammonia nitrogen (NH(3)-N) was not affected with the increased soybean hulls levels, but volatile fatty acids (VFA) were linearly (P < 0.05) increased. Slurry pH and ammonia (NH(3)) emissions were significantly decreased by the addition of soybean hulls (Linear, P < 0.05). Conversely, slurry hydrogen sulphide (H(2)S) emissions exhibited an increase with the addition of soybean hulls (Linear, P < 0.10). Our data indicate that soybean hulls inclusion can decrease slurry pH value and NH(3) emission without any negative influence on growth performance.