DURATION OF FARROWING IN SOWS AND PERINATAL-MORTALITY OF PIGLETS DEPENDING ON GENOTYPE AND HOUSING-SYSTEM

Effects of genotype and housing system on parturition and perinatale piglet losses were studied on 112 sows. The results can be summarised as: The duration of birth per piglet was significantly shorter in crossbred sows than in purebred sows. In purebred sows litter weight was 1.4 kg lower than in crossbred sows. Between genotypes there were no differences found in average birth weight per piglet. Crossbred sows had a higher number of piglets born per litter and their number of piglets stillborn was lower than in purebred sows. The parturition was significantly affected by housing system for sows during pregnancy. In sows after single housing delivery was delayed by 75 min. compared to sows of group housing. This is reflected by the number of piglets stillborn. In litters after group housing the number of piglets stillborn was lower (0.5 piglets stillborn per litter) than in litters after single housing (1.02 piglets stillborn per litter). In sows after group housing, however, the number of mumified piglets was twice the number as in sows after single housing (0.60 versus 0.29 numified piglets per litter).