This study evaluated the field applicability of a urea structural analogue (PPDA) as a pre-treatment agent for mitigating ammonia in commercial swine farms.PPDA was applied to slurry at two farms operating under different seasonal and management conditions: Farm A (winter) and Farm B (summer).In Farm A, the treatment group showed a 21% lower average ammonia concentration than the control (control: 64.32 ppm; treatment: 50.89 ppm), with an approximately 30% reduction observed after the first application.Normalized ammonia levels (C/C) also changed less in the treatment group (0.82-1.72) than in the control (1.57-3.23),indicating suppression of ammonia accumulation.In Farm B, the treatment group exhibited higher absolute ammonia concentrations; however, normalized real-time NH 3 (Ct/C) showed a steeper decline after PPDA application, with regression slopes of -0.003614 for the treatment and -0.00059 for the control.This suggests a stronger relative reduction in ammonia following PPDA application despite higher initial concentrations.Odor-related compounds, including H 2 S and VFAs, did not show consistent changes, supporting the nitrogen-specific action of PPDA.Differences between farms were attributed to uncontrollable field factors such as ventilation rate, pit cleanliness, slurry retention time, and seasonal effects.Overall, PPDA showed mitigation potential under conditions where ventilation is limited and slurry accumulation is substantial, highlighting the importance of farm-specific operational variables when evaluating field performance.
Lee et al. (Thu,) studied this question.