Environmentally Compatible Fattening Pig Husbandry III : Daytime-Related Effects

Abstract

As part of continuous emission measurements in the experimental stall for fattening pigs in Hohenheim, a conventional stall with fully slatted floor and forced ventilation (FSF) was compared with a naturally ventilated kennel housing system (KN) during four fattening periods from October 1999 until April 2001. The third contribution to the article series about environmentally compatible fattening pig housing focuses on the description and analysis of daytime-related effects and the course of emissions. The courses of three measuring periods during the second fattening period which were chosen as examples as well as multiple regression analyses were studied to answer the question of what variables mainly determine the different daily courses of NH3 - and CO2 -emission and to what extent emission reduction strategies may influence the daily course. In accordance with the literature, the FSF housing system largely showed a positive correlation between temperature, volume flow, and emission. In the KN housing system, however, a reduction in emissions was observed combined with increasing volume flows, which generally occurred in particular at low temperatures. Animal activity, which was strongly influenced by the feeding times, was reflected by significant peaks of CO 2 concentration and –emission as well as NH3 emission. In the FSF housing system, the percentage of variance in the daily course of the emission rates during the selected measuring periods which can be explained through variables able to be used for practicable stall climate recording and –control and able to be influenced through measures of emission reduction ranged between 12 % and 75 % for NH3 and between 39 % and 47 % for CO2 . In the KN housing system, the percentage of explainable variance is lower at 52 % to 64 % (NH3 ) and 18 % to 28 % (CO2 ).