
The genome, which was published in the journal GigaScience, is essential for genetic improvement using gene editing or genome-assisted selection and will contribute to the genetic improvement of better breeds of catfish for the fish farming industry- multimillion dollar cats, according to a press release from Auburn.
Catfish farming is the largest aquaculture industry in the United States, accounting for about 70 percent of the nation’s total aquaculture production. The main fish used for breeding purposes is a hybrid produced by breeding male blue catfish with female catfish.
“The hybrid catfish is superior in terms of growth and disease resistance,” according to Xu Wang, assistant professor of comparative animal health genomics, who is one of the project leaders.
“Faster growth means more profits. Originally farmed fish were mostly river catfish, but three major bacterial pathogens have resulted in a 40% loss in production and over $100 million in annual economic damage in the US industry alone . The hybrid mix of blue catfish and channel catfish improved disease resistance and halved mortality.
Even so, Wang says there is a critical need for further genetic improvement using genomic methods.
“The channel catfish genome was mapped in 2016 by John Liu’s lab in Auburn [now at Syracuse University], but the blue catfish genome was not available until we published it,” Wang added. “Our high-quality blue catfish genome meets urgent needs to achieve the long-term goal of improved growth, feed utilization, stress and disease resistance, and reproduction.”
Wang was the main author of the GigaScience paper, assisted by Haolong Wang, doctoral student in biomedical sciences. The veterinary researchers worked closely with a team led by Professor Rex Dunham, an internationally recognized authority on the genetic improvement and gene editing of catfish.
“It’s a fantastic step forward,” Dunham said. “There have been many genetic improvement projects related to gene transfer and gene editing that were not possible for blue catfish without it. So we couldn’t do parallel work with what we’re doing with channel catfish. Since a hybrid between channel and blue is the best genetic type for the catfish industry, it also limits what we could do with these tools to improve the hybrid.
“That roadblock is now gone. The availability of the blue catfish genome opens up a huge treasure trove of markers that we can use for other approaches, such as marker-assisted selection, and also gives us many other tools to distinguish and track different genetic types of fish. -blue cat. Thanks to this research, we are much less limited than before.