Alterations in the epigenetic programming of hatchery-raised steelhead trout could account for their reduced fertility, abnormal health and lower survival rates compared to wild fish, according to a new Washington State University study.
The study, published May 18 in Environmental Epigenetics, establishes a link between feeding practices that promote faster growth, as well as other environmental factors in fish hatcheries, and epigenetic changes found in the sperm and red blood cells of of steelhead trout.
“Despite being genetically very similar, steelhead trout raised under hatchery conditions don’t have the same level of health and survivability of wild-raised fish,” said Michael Skinner, study co-author and professor in the WSU School of Biological Sciences. “This research provides a molecular explanation for why we are seeing these differences.”
Skinner is an expert in the field of epigenetics, which is the study of molecular factors and processes around DNA that regulate genome activity independent of the DNA sequence.