Producers, hauliers and abattoirs could achieve welfare and financial gains and improve consumer satisfaction by working together to avoid mixing groups of pigs before slaughter.

That’s according to Scottish Agricultural College researchers ,whose latest study found pig aggression is a genetic trait that affect welfare, carcass value and meat quality.

The SAC-led study, which formed part of a pan-European project, found that pigs with aggressive “personalities” cause more fighting and experience more stress when mixed in unfamiliar groups.

Mixing of pigs pre slaughter can:

• Increase fighting
• Increase pig stress levels
• Reduce carcass value
• Affect meat quality

 

The findings also open the way for reducing pig aggression through genetic selection, according to SAC Behavioural Scientist Dr Rick D’Eath

“The mixing of pigs into new groups commonly occurs pre-slaughter. Increased fighting presents an obvious welfare concern and can also reduce carcass value when scratched or damaged areas have to be discarded.

“In addition, the pigs we studied which experienced stress prior to slaughter had less acidic meat post-slaughter, which can reduce its eating quality. Therefore, reducing pig aggression, particularly pre-slaughter, could bring welfare and financial benefits while reducing waste and improving meat quality,” he says.

“Producers, hauliers and slaughterhouses could work together to avoid the mixing of pigs in unfamiliar groups before slaughter, such as by ensuring that farm groups of pigs are penned separately on the truck and at lairage. In the longer term, the study also opens the way for tackling the issue of pig aggression using genetic selection,” he says.