The Impact of Microclimate Parameters on Odour Emissions from Pig Production in Spring

The aim of this study was to examine the impact of inside temperature and relative humidity, ventilation rate and gas concentrations (NH₃, N₂O, CO₂) on odour emissions from deep-litter piggery. The studied facility had temperature-controlled mechanical ventilation. The measurements were conducted from March to June 2014. During the research, selected microclimate parameters, as well as number and mass of animals were monitored and air samples were collected (two samples of air in each series of measurements). Temperature and relative humidity were measured using Testo 435-4 multifunctional measuring instrument. To measurements of gas concentrations was used the photo-acoustic spectrometer Multi Gas Monitor Model 1312. The concentration of odours in the air samples was determined by dynamic olfactometry with the TO 8 olfactometer, according to PN-EN 13725:2007. The odour concentration ranged from 450 to 2004 ou_E · m^–3 (mean 1048 ou_E · m^–3) and the mean odour emission factor was from 5.76 to 46.79 ou_E · (s · pig)⁻¹ (mean 20.93 ou_E· (s · pig)⁻¹.The statistical analysis showed that the inside temperature explained most of the variability of the odour concentration and the relationship was described by equation: c_od = 5634 – 197 T_inside (R² = 0.82, p ≤ 0.05). For odour emission factor, two parameters: the inside temperature and ventilation rate, explained most of the variability, according to the equation: EF_od = 108 + 1939 VR – 5.5 T_inside (R² = 0.81, p ≤ 0.05).