Effects of size, shape and partition type of pen on excretory behavior of domestic pigs

Many factors affecting elimination site preference of domestic pig were discussed. A 23 factorial experiment with two pens per treatment was conducted to examine the factors affecting the excretory behavior of growing-finishing pigs. The factors investigated were size(14.4 m2 or 9.6 m2), shape(length: width=1.5:1 or 1:1) and partition type(open or closed) of the pig pen. Every pen was divided into 15 regions. The frequency of elimination behavior in every area was analyzed with OBSERVER software. Elimination area was defined as the sum of areas in which the frequency of elimination behavior was over 80%. Pen shape and partition type had no effect on eliminative site preference and area. The elimination area was larger in pen with the size of 14.4 m2 than that with the size of 9.6 m2 (Mann-Whitney U Test, P＜0.001), and it tended much larger with the growth of pigs(Fridman Test, P＜0.05).