Influence of internal planning system differences on emissions of aerial pollutants in laying hen houses.

摘要

The air in livestock buildings includes a dense of dust particles, microorganisms and gases. Pathogens and microorganisms cause directly chronic and allergic diseases in human and animals. Respiration and metabolism activities of animals, waste management and manure handling systems and other livestock production activities are major sources of gases such as ammonia (NH₃), carbon dioxide (CO₂) and methane (CH₄). These aerial pollutants cause global warming, water pollution and soil acidification. The impact of different internal planning systems on ammonia, carbon dioxide and methane gases emissions were investigated at four laying hen houses located near Ankara Province, Turkey. These laying hen houses include two battery-cage type systems and two Californian type systems that are commonly used in production which capacity, animal breed, age, live weight and feeding differences are at least as far as possible. Temperature, relative humidity, NH₃, CO₂ and CH₄ gases emissions were measured by using common methods in two replicates of each laying hen house over 24 h for five days period during winter (2010 January), early spring (2011 March-April) and summer (2011 July). Mean concentrations and emissions and other variance components per planning systems were estimated. In winter period, mean concentrations of NH₃, CO₂ and CH₄ gases have been found in orderly 7.46, 1049.50 and 3.52 ppm at battery-cage type systems and 12.24, 1314.95 and 7.08 ppm at Californian type systems. These values were 16.96, 668.94 and 3.15 ppm at battery-cage type system and 20.46, 906.30 and 9.04 ppm at Californian type system in early spring. During the summer, mean concentrations of gases were 35.14, 423.71 and 6.62 ppm at battery-cage type system and 37.75, 471.14 and 10.57 ppm at Californian type system. According to the statistical analysis and evaluation, differences of planning systems has a significant impact on emissions of NH₃, CO₂ and CH₄ gases in laying hen houses. Particularly during the summer period, increases of relative humidity, NH₃ and CH₄ levels have been found important in Californian cage systems. In battery-cage type system, temperature and relative humidity values were higher than in other planning system. Carbon dioxide concentrations increased at low air speed and high relative humidity conditions in all hen houses. The result of this research is using good ventilated battery-cage type system for laying hen houses that can help to reduce NH₃, CO₂ and CH₄ emissions in indoor and outdoor environment.