10 May 2002

ANTI-SOCIALTABLETOPPEDBYDUROCS

BREED differences can influence the amount of tail-biting and other anti-social behaviour among pigs, according to Kate Bruer, of Newcastle University.

She said the pigs genetic make-up has a strong influence on its foraging behaviour and this natural instinct is often reflected in the way it behaves towards other animals when housed.

Having compared three breeds: the Duroc, Large White and Landrace, she concluded that the Duroc was more likely to bite the tails or ears of its penmates. She also found that the Landrace bit other pigs in the pen less often than the other two breeds, although it performed the most belly-nosing out of the three.

"Early weaning and a lack of suitable feed can lead to these harmful social behaviours, which are fuelled by the pigs need to forage," explained Dr Bruer.

"The Duroc was the most interested in investigating its surroundings – it is said to be a robust and active breed and its reputation was confirmed by this study.

"The Landrace is supposed to be fairly timid and flighty and it did show signs of this, although being mixed with more lively Durocs could have exaggerated these traits."

Dr Bruer studies used a tail-chew test on 300 young pigs, where she hung a piece of rope from the side of a flat-deck cage. The number of times each pig chewed the rope gave an indication of the amount of harmful social behaviour carried out by individual animals.

Rope chewing

She also found that pigs sired by one particular Duroc boar chewed the rope three times more often than pigs by other boars. But she admitted there was little general information on the influence of different sires within breeds. This was largely because most commercial units tended to use large numbers of sires, which made trial work difficult to evaluate.

Dr Bruer is planning to continue her investigation into sire effects and is also hoping to test out a theory that smaller pigs are more likely to be responsible for biting their penmates. &#42

Some breeds may be more prone to

tail-biting than others, says Kate Bruer.

&#8226 Durocs bite more.

&#8226 May be sire related.