Study on incidence of respiratory disease according to configurations of structural and ventilation system using aerodynamic approaches

The typical diseases for pigs in Korea are porcine epidemic diarrhea (PED), porcine reproductive and respiratory syndrome (PRRS), post-weaning multi-systemic wasting syndrome (PMWS), and porcine respiratory disease complex (PRDC). The main factors for the occurrence of these diseases, specifically the respiratory diseases, are the environmental conditions, particularly ventilation inside the pig house. Considering that Korea has 4 distinct seasons, the environmental conditions in a pig house change every season. The purpose of this study was to find the relationship between the structural configuration of the ventilation system of a pig house and the occurrence of pig respiratory disease. It was analyzed that there is an effect of internal airflow distribution to internal disease dispersion in a pig house. Several field experiments were conducted at several commercial pig farms to understand the environmental control in relation to disease occurrence. To overcome the difficulties of conducting field experiments and obtaining internal airflow visualization quantitatively and qualitatively, computational fluid dynamic (CFD) and building energy simulation (BES) technologies have been simultaneously used. The accuracy of the simulations was preliminarily examined and improvements were made in the model based from the seasonally collected farm data.