PSVI-4 - Effect of Phytogenic Feed Additives on Ammonia Emission in Finishing Swine

Abstract: Two independent studies were conducted to evaluate the effects of a commercially available phytogenic feed additive (essential oils blend and saponins) to reduce ammonia (NH₃) emission in finishing swine. In each experiment, 72 barrows and gilts (Exp. 1: 30.7±3.35kg; Exp. 2: 26.2±1.85kg) were used during 110 and 77 days, respectively. In each experiment, pigs were housed in eight gas-tight sealed chambers under controlled climatic conditions. Each chamber had three pens with a fully slatted floor. Pigs were allotted into 24 pens (3 pigs/pen). Treatments were assigned to the chambers (4 chambers/treatment). Dietary treatments were: 1)Control and 2)Phytogenics (100g/MT Aromex^®Pro, Delacon Biotechnik GmbH). Diets were offered ad-libitum and in mash form. Ammonia emissions were measured during the last 14 days of the experimental period of each study. Ammonia emissions were calculated per chamber as the experimental unit. Air NH₃ concentration in the chambers was measured by a Photoacoustic Gas Monitor System INNOVA every 13 minutes. The ventilation rate of each chamber was used to calculate the emission rate. Data were analyzed using PROC MIXED of SAS. In Exp. 1, the phytogenics treatment significantly reduced by 19.5% the daily NH₃ produced per animal, and by 20% the NH₃ emission per kg body weight gained compared to the control treatment (12.94 vs. 16.07 g NH₃/animal/day, P< 0.001 and 13.73 vs. 17.23 g NH₃/kg BWG, P=0.011). Similar findings were observed in Exp. 2, the phytogenic treatment significantly reduced by 19.8% the daily NH₃ produced per animal and by 21% the NH₃ emission per kg BWG compared to the control treatment (14.40 vs. 17.95 g NH₃/animal/day, P=0.01 and 13.58 vs. 17.18 g NH₃/kg BWG, P=0.01). In conclusion, the results suggest that the phytogenic feed additive used in the present studies can be implemented as a nutritional strategy to reduce NH₃ emissions in finishing swine.