Scientists aim to breed out sow aggression

Scientists at Michigan State University (MSU) are hoping to help pig producers improve herd welfare thanks to a $1 million project aimed at finding ways to breed less-aggressive sows.

Working with research teams across the world, scientists will use state-of-the-art technology, including videos and heat sensors, to identify animals that are less likely to show aggressive behavior, such as fighting and biting.

They hope that by closely analyzing pig behaviors they will be able to build new genetic models, eventually enabling breeders to select pigs for good social behavior at a commercial scale for the first time.

While pig breeding has traditionally focused on improving growth and meat quality, little work has been done on breeding out aggressive behaviors that can lead to injuries and affect pig health and growth.

But as the US pig industry moves toward its goal of keeping pregnant sows in larger groups by 2020, reducing aggressive behavior through breeding is becoming increasingly important, said project leader Juan Steibel, associate professor in the MSU Department of Animal Science.

“Keeping pigs in larger social groups solves some problems but creates others,” Steibel said. “Fortunately, we now have the technology to address those problems.”

As part of the three-year study, funded by the USDA’s National Institute of Food and Agriculture, with support from the Michigan Alliance for Animal Agriculture and the National Pork Board, Steibel and his team will develop previous research that uncovered a link between pig genetics and aggressive behavior.

Using innovative video technology, they will monitor large numbers of pigs at once to identify individual animals which are less aggressive than others.

The team will also make use of infrared technology, currently being developed by Scotland’s Royal University College, to identify any increases in body temperature caused by fighting.

By analyzing the data, Steibel and his team — including colleagues at the University of Buenos Aires —  will be able to build genetic models that will allow breeders to select less-aggressive pigs, helping them improve herd performance.

“So far, because data collection has been limited to small numbers of pigs, our breeding models have not been well-developed to incorporate information on their social behaviors,” Steibel added.

“Aggression has a substantial impact on pig group health, and we want to incorporate that into breeding models alongside traditional performance measures like weight gain.

“Getting these systems to work well together is very challenging, but now it’s feasible. Ten years ago, I would have called it science fiction.”