
Published on March 27, 2023
Continuing to expand availability of BCWD resistant eggs
Maintaining healthy trout is crucial in our operations and for our customers. To ensure high quality trout, we continue to expand the use of genomic technology for enhanced resistance to Bacterial Cold Water Disease (BCWD), a highly damaging disease in the trout industry.
Bacterial Cold Water Disease (BCWD) is a major concern for farmers in almost every region. Farmers that experience BCWD in their operations see high mortality and an increased cost of antibiotics for treatment. The fish that are infected but survive have a reduced appetite and slower growth, which negatively impacts economic performance. In addition, at harvest trout previously infected with BCWD frequently exhibit spinal deformity. This can cause downgrading at the processing plant leading to less returns.
Genomic selection to reduce the impact of BCWD
In 2013, Troutlodge and the USDA formed a long-term partnership to help eliminate the issue of BCWD. The process uses genomic selection by analyzing DNA of the animal to select for resistance to BCWD. In 2015, we first applied of genomic selection to commercial rainbow trout populations. Based on laboratory challenges, results showed that the use of genomic selection doubled the selection accuracy compared to traditional selection methods. In 2017, we started to sell Troutlodge eggs specially selected for enhanced resistance to BCWD, and the following year we expanded genomic selection to additional strains for extended commercial availability. From 2019 until the present, we continue to see genetic improvement in each generation for different populations. Since 2019, the expanded use of genomic selection into other strains was aided by the development of a custom SNP chip for genotyping our broodstock, and as a result, we were able to offer enhanced resistance to BCWD in our November strain in 2022.
The same technology that was used to improve BCWD resistance was also applied to the November 2022 population for improvements against Infectious Hematopoietic Necrosis Virus (IHNV) and offered for the first time as a commercial product.
We continue to expand the use of genomic technology to improve our February and August strains with the target of having enhanced resistance to BCWD year-round. This goal will be accomplished in 2024 when all 4 of our strains will show enhanced resistance to BCWD.
Interested in learning more about fish health? Read our Trout Logic Guide: Keeping Your Fish Healthy