A farokrágás megjelenésének okai és kivédésének lehetőségei a modern sertéstartó rendszerekben - A jelenség etológiai szempontú megközelítése

Abstract

SUMMARY Tail biting is one of the most serious welfare challenges in the modern pig industry. There are several attempts to prevent or treat this abnormal behaviour which typically develops after weaning and during the fattening stage. The life of modern pig breeds has changed dramatically compared to their ancestor, the wild boar. However, their behavioural repertoire is still the same and has not changed fundamentally over thousands of years of domestication. In their natural habitat pigs are exploring their environment, searching for food, rooting or chewing, in 75% of their active period of the day. In modern pig houses animals are kept in small and fundamentally barren environment compared to the wild. Food is provided in food trays, which are often too small for the whole group to feed altogether. Consequently, the smallest and weakest individuals are displaced from the feeder by their more developed counterparts. Not only the displacement, but also the chewing and rooting deprivation may trigger the motivation to bite pen-mates’ tails or even ears and flanks. When considering both the motivational background and form of the behaviour, there are at least 3 different types of tail biting behaviour, e.g. two-stage, sudden-forceful and obsessive, with large individual differences in response. There are several environmental and individual factors that predispose a pig to develop biting, become a victim or stay neutral (neither bite nor being bitten by others). Tail biting may be prevented by tail docking, and about 90% of fattening pigs are docked in the EU. However, it has been reported that 2 - 5% of docked pigs are still bitten by pen-mates. The proportion of bitten animals in undocked stocks has been found to be up to 30%. Although genetic selection for more tolerant individuals might be a promising solution for breeders, there are preventative measures that can be done to decrease the occurrence of this unwanted behaviour. Detecting the first signs of the outbreak is crucial. Early removal of the biters and bitten animals, and providing straw or any other chewable material can strongly reduce the occurrence of tail biting.