A U.S. university says it has developed a strain of pigs that resist an incurable virus disease.
The disease is porcine reproductive and respiratory virus, which is known as síndrome disgenésico y respiratorio porcino in Costa Rica.
Scientists at the University of Missouri were able to modify the genetic structure of pigs so that the animals do not produce a protein that is vital for the spread of the virus.
Pig production is a major agricultural industry in Costa Rica, and both the U.N. Food and Agricultural Organization and the Servicio Nacional de Salud Animal acknowledged that the disease is present here.
A 2008 decree requires farmers and veterinarians to report cases of the disease when they find it.
Animals that are affected do not gain weight rapidly and have a high mortality, said the university. To date, no vaccine has been effective, and the disease costs North American farmers more than $660 million annually, it added.
In addition to Missouri, researchers involved were from Kansas State University, and Genus plc.
The University of Missouri said that it had signed an exclusive global licensing deal for potential future commercialization of virus resistant pigs with the Genus.
Randall Prather, an animal science professor, said that the virus needs help from a protein to spread inside pigs. The protein is called CD163.
“We were able to breed a litter of pigs that do not produce this protein, and as a result, the virus doesn’t spread,” he said. “When we exposed the pigs to PRRS, they did not get sick and continued to gain weight normally.”
The process was genetic modification but instead of adding a foreign gene to the pig DNA, the scientists edited out the gene that produces the protein.
While the pigs that didn’t produce CD163 didn’t get sick, scientists also observed no other changes in their development compared to pigs that produce the protein, said the university.
“At the end of our study, we had been able to make pigs that are resistant to an incurable, untreatable disease,” said Kevin Wells, co-author of the study and an assistant professor at Missouri. “This discovery could save the swine industry hundreds of millions of dollars every year. It also could have an impact on how we address other substantial diseases in other species.”