Comparison of Natural and Forced ventilation Systems in Nursery Pig Houses

Pig producers prefer to have automated control systems installed in their indoor environments because it reduces labor and enhances control precision. The effectiveness of two ventilation systems (forced and natural) were examined in several nursery houses and the overall distributions of environmental parameters and productivity indicators, such as temperature, humidity and air speed, ammonia concentration, weight gain, and feed efficiency were analyzed during the winter (19 November-16 December 1999) and the summer (13 May- 18 June 2000). These experiments were conducted at the Collegiate Experiment Animal Farm of Seoul National University. Results showed that the indoor temperature of the forced ventilation house was 3°C to 4°C higher than the natural ventilation house during the winter and ammonia concentration in the forced ventilation house was approximately 2 ppm lower than the natural ventilation house in both seasons. Also, feed requirement was 10% higher during the winter and 7% higher during the summer in the forced ventilation house. Energy costs for the natural ventilation house were two times more ($20.84/yr/head) than that of the forced ventilation house ($10.21/yr/head).