Brain proteomics of rainbow trout at certain maturation stages: biological insights and fish by-products processing...

For the first time, the brain proteomic profiles of rainbow trout Oncorhynchus mykiss (Walbaum, 1792) at two maturation stages were described and discussed. Maturation and reproduction are critical stages in the fish life cycle, but the biochemical and morphophysiological processes underlying these stages are not well understood. The reactions that occur in the fish brain during maturation, regulating the reproductive process and accompanying metabolic changes, are of particular interest. O. mykiss is an economically significant commercial species of salmonid fish that is a model organism for biological research. We analyzed the brain proteomes of rainbow trout at different stages of gonadal development, including stages II-III (developing) and stage V (spawning). It was revealed that the brain proteomes differed in terms of proteins involved in lipid metabolism, immune responses, stress response, cell structure, and oocyte development. These findings provide valuable insights into the complex processes that occur during fish maturation and can contribute to our understanding of reproductive biology. The biochemical differences in the brain at different stages of development are shown, as well as the fact that the by-products of commercial fishing, in this case, heads and brains, can be used to extract antimicrobial proteins and peptides.