Animal agriculture, like other animal-related industries, is a constantly evolving enterprise, informed by results from scientific studies focused on the best methods to raise livestock so as to minimize animal discomfort and disease.
With increasing concerns about the impacts on antibiotic resistance resulting from the use of antibiotics in livestock, methods to keep livestock healthy without relying on antibiotics has become the focus of scientific research.
Hence, the ability to modify animal genes to protect them from disease infection has been an area of increased interested.
Genus, a world-leading animal genetics company, recently announced “the discovery of the first pig resistant to Porcine Respiratory and Reproductive Syndrome virus (‘PRRSv’) in collaboration with the University of Missouri. An exclusive global license has been signed enabling Genus to develop and commercialise the technology.”
PRRSV is the etiologic agent of PRRS, an economically devastating, pandemic disease of swine that is typically characterized by reproductive failure in breeding herds and respiratory problems and growth retardation in growing pigs. Two PRRS outbreaks were first reported in the late 1980s in North America and central Europe. The disease is now found in most pig-producing countries and affects the swine industry and food safety worldwide, causing enormous economic losses each year. In the US, the annual loss due to PRRS is estimated to exceed $500 million. Over the last decade, this genetic/antigenic diversity of PRRSV has expanded continuously and rapidly, highlighting the dynamic nature of PRRSV evolution and epidemiology.
Using gene editing technology, Genus and its subsidiary the Pig Improvement Company (PIC) reportedly made “small changes . . . to inactivate a single gene from the pigs that produces a protein, known as CD163, [which] the PRRS virus requires for infection to occur.”
The results allow the production of PRRSv resistant pigs.
“Using precise gene editing, the University of Missouri was able to breed pigs that do not produce a specific protein necessary for the virus to spread in the animals. The early stage studies conducted by the University demonstrate these PRRSv resistant pigs, when exposed to the virus, do not get sick and continue to gain weight normally. Genus will continue to develop this technology, and we expect it will be at least five years until PRRS resistant animals are available to farmers.”
Since there is no cure for PRRSV and the disease results in “the suffering or death of millions of pigs and piglets each year,” this type of innovative advance in science is considered a breakthrough.
 While antibiotics are not effective in treating viruses like PRRSV, such infections are often accompanied by secondary bacterial infections which are susceptible to targeted antibiotic treatment.
 This information is from Utah State University’s submission to USDA’s Current Research Information System (CRIS).