Impact of different types of rubber mats for gestating sows on lying and walking comfort and their potential of ammonia volatilization

In the current thesis different types of rubber mats with different softness degrees and surface profiles were investigated for lying and walking comfort as well as their potential of ammonia volatilization. Lying comfort was analyzed with the pressure measurement system (5400 NTL, Tekcan Inc., Boston, MA) in sternum and half recumbent lying position. Pressure load (N/cm²) and contact area (cm²) were recorded under sternum, belly, ham and shoulder for sows with different weights. The investigation of pressure load under the carpal joints were recorded in half and full kneeling position during lying down, additionally. Pressure load was highest under the sternum sternal position and under the shoulder in half recumbent position. The very soft rubber mat with a penetration depth of 43 mm reduced significantly pressure load under both body parts in comparison to concrete. Contact area was only significantly affected by floor type under the sternum in sternal position. Walking comfort was estimated per kinematic gait analysis on two rubber mats with different surface profile (rough vs. smooth) in comparison to concrete slats. 15 sows were analyzed for different gait parameters (e.g. walking speed, stride length, stride time) in repeated measurement. The analysis of gait parameters was conducted on fore and hind limb, single-sided. Walking speed increased with measurement order over all floors and was significantly affected by test repletion. There were no significant differences in stride parameters in fore and hind limb between floors except the swing time on hind limb. The ammonia volatilization was analyzed in a laboratory and field trial. In laboratory trial four rubber mats with different surface profiles in comparison to concrete were artificially fouled with pig feces and synthetic urea solution. In a field trial ammonia volatilization was investigated in lying area on rubber mats with a slope in comparison to concrete slats. Ammonia volatilization was estimated with a static chamber. In field trial ammonia volatilization was 10-fold higher than in laboratory trial and did not differ between rubber mats and concrete slats.