Indoor climate of pigsty with deep litter and liquid manure system in summer
Institute of Technology, Estonian University of Life Sciences,Kreutzwaldi St. 56, 51014 Tartu, Estonia; e-mail: boris.reppo@emu.ee
Abstract:
Construction of big deep-litter pigsties and pigsties without litter (using liquid manure systems) is becoming more extensive. Due to lack of knowledge concerning animal-keeping in big pigsties, it has become necessary to study the work environment in pigsties and, in particular, their indoor climate. In order to determine the impact of the outdoor climate, different methods for animal-keeping and tending activities on indoor climate during summertime, the air temperature, relative humidity, air velocity and contents of oxygen, carbon dioxide and ammonia were measured on a daily basis at the height of 1.5 m from the floor above the pigsty in the centre of deep-litter (800 fattening pigs) and liquid manure system (600 young pigs) pigsties. Simultaneously outdoor air temperature and relative humidity were measured. Data Logger equipment with relevant sensors and Gas Monitor Pac III were used for studying the indoor climate. Hydrolog equipment was used for measuring the parameters of outdoor climate. Measurement results were processed by using computer programmes AMR Win Control, HW3 and MS Excel.It turned out that during summertime the indoor climate of pigsties was most affected byoutdoor climate and tending works. The daily average indoor temperature (17.04 and 17.60°C respectively; outdoor temperature, 18.15 and 8.75°C) and relative humidity (68.11 and 78.59% respectively; outdoor relative humidity, 71.88 and 84.19%) remained within recommended limits for animals in the deep-litter pigsty and in the pigsty without litter. However, partial floor heating had to be used in the morning in order to ensure optimum indoor temperature and relative humidity in the pigsty for young pigs. Due to good ventilation in the pigsties the daily average contents of carbon dioxide (0.06 and 0.07%) and ammonia (20.9 and 8.7 ppm) remained within standard limits. Ammonia content in pigsties was higher during tending works, reaching 43 and 27 ppm. As a result of the study, the graphical and empirical relationship was determined between ammonia concentration and indoor air both in terms of air temperature and combined effect of temperature and relative humidity.
Key words:
air temperature, air velocity, ammonia, carbon dioxide, Data Logger, outdoor climate, oxygen, relative humidity, tending activities, ventilation