Assessment of Housing Design Effects on Thermal Comfort and Productivity of Intensively Managed Pigs in Nigeria

This study assesses the effects of pig housing design features on thermal microclimate, animal behaviour, stress indicators, and productive performance in intensively managed commercial pig units in Nigeria, contributing evidence for improved tropical pig housing design standards. Pig housing in tropical Nigeria faces the dual challenge of providing protection from heavy rains while maintaining thermal environments that support productivity. Current housing designs in many Nigerian pig farms create chronically heat-stressed conditions that reduce daily gain and reproductive efficiency, but design-performance relationships have not been systematically documented. This study instruments 20 commercial pig units of varying housing designs in Anambra, Kaduna, and Ogun States with microclimate monitoring equipment recording temperature, relative humidity, air velocity, and temperature-humidity index at one-hour intervals over six months. Housing design variables including roof material, ventilation opening area, orientation, insulation, and building geometry are documented. Productive performance data including average daily gain, feed conversion ratio, sow farrowing rate, and litter size are extracted from farm records. Animal behaviour and welfare indicators including stereotype frequency, aggression rate, and skin lesion scores are assessed through video observation. Multiple regression analysis identifies housing design predictors of thermal comfort and performance. Findings reveal that roof material (fibre cement versus galvanised steel) accounts for the largest variance in maximum midday temperature, with fibre cement maintaining peak temperatures 5.8 degrees Celsius lower. Cross-ventilation opening area above 20 percent of floor area significantly reduces temperature-humidity index below the critical pig stress threshold. The study recommends standardised thermal design criteria for Nigerian tropical pig housing.

Keywords: pig housing design, thermal comfort, tropical climate, productive performance, Nigeria.