Purdue University researchers believe they can manipulate hog genes to remove the gene responsible for overly aggressive behavior in some hogs.

Keeping hogs happy could improve lean growth by 25% without increasing feed, says William Muir, professor of animal science and director of Purdue’s genome sequencing facility.

Muir bases that prediction on his work in chickens which showed that competition for food had a major impact on animal survival and production.

Applying genomic techniques in hogs, Muir found that there was an overall deficiency in lean growth because the hogs were fighting for food. Dominant hogs eat more than they need, wasting nutrients, he explains, while the less aggressive penmates don’t get enough to eat to grow to their potential.

"Another reason that the hogs don’t grow to their potential is that when they are fighting, they produce lots of heat, which requires energy to produce," says Muir.

The Purdue scientist hopes to use a genetic scan to find genes that influence behavior in hogs. "We’ve been able to use this method in quail to achieve more than a 200% gain in growth. We know that this isn’t just pie in the sky," he says.

Using marker-assisted selection, genes can be integrated into breeding nucleuses to create less aggressive hogs, or the genes can be cloned and moved directly into hog populations, says Muir.

The gene change would be a win-win situation for all involved. "The farmers win because they get more output with no additional input. The animals win because they are less stressed, and society wins because we would all like to see our animals treated in a way that improves their well being," he says.

For more information, visit www.agcom.purdue.edu.