Evaluating ventilation rates based on new heat and moisture production data for swine production

Heat and moisture production (HMP) rates of animals are used for calculation of ventilation rate (VR) in animal housing. New swine HMP data revealed considerable differences from previously reported data. This project determined new design VRs and evaluated differences from previously recommended VRs. The swine production stages evaluated included gestation, farrowing, nursery, growing, and finishing. The ranges of ambient temperature and ambient relative humidity (RH) evaluated for VR were -25°C to 15°C in 10°C increments and 15% to 75% in 15% increments, respectively. Indoor set points for temperature and RH were, respectively, 15°C, 20°C, 25°C and 60%, 70%, 80% for all five ambient stages. The results showed that the old VR for moisture control was 54%, 30%, 69%, 31%, and 53% lower than the new VR for the gestation, farrowing, nursery, growing, and finishing stages, respectively. Updated recommendations for ventilation are necessary for designing and managing modern swine facilities.