The Porcine Reproductive and Respiratory Syndrome (PRRS) virus has plagued the U.S. since 1987. Infected pigs have trouble reproducing and gaining weight, and they have a high mortality rate. There’s no vaccine, and losses in North America total around $660 million annually.

That all could change after researchers from the University of Missouri, Kansas State University and Genus, plc have successfully bred pigs that aren’t harmed by PRRS.

Read more from AgWeb.com: "These Pigs Could be Worth $660 Million"