Temperature, air humidity and air pollution levels in breeding pig houses

A study was undertaken to provide practical information concerning the frequency of temp. and RH measurements required to obtain a good estimate of their averages and of their daily variations, and to determine the relationships between ammonia, carbon dioxide and bacterial concn in a pig house. Measurements were made in 9 artificially ventilated farrowing or weaner houses with slatted floors. Temp. and RH were measured every 20 min for 7 d. Sensors were placed inside buildings in the middle of the houses, 0.8 m above floor level, and outside the buildings. Data were recorded using a datalogger. Ammonia and carbon dioxide concn were measured using 8 h Gastec diffusion tubes. Three readings were taken in the same location at 2-day intervals. The airborne bacterial concn was measured with a 6-stage Andersen sampler. Bacteria colony forming particles (BCFP) were collected by impacting onto agar-filled petri dishes which are placed in an incubator for 24 h prior to counting the colonies formed. Results are discussed, indicating no significant correlation between the 3 measures of pollution (NH3 and CO2 concn, BCFP levels) despite careful microclimate control.