Channel catfish (Ictalurus punctatus) is a widely consumed freshwater fish known for its nutritional value but is highly prone to spoilage. This study investigated the quality changes of catfish muscle tissue under refrigeration and freezing through physicochemical, metabolomic, and microbial analyses. Results revealed that sensory scores decreased significantly during storage, with frozen samples maintaining similar scores to refrigerated ones after extended periods. Protein degradation and lipid oxidation, indicated by TVB-N and TBARS levels, were more pronounced during prolonged freezing. Metabolomic profiling identified 261 differential metabolites under long-term freezing, including elevated phosphatidylcholines, sphingomyelins, and disrupted amino acid pathways. Shifts in spoilage-associated microbial genera, such as Pseudomonas, and the correlations between microbial genera and specific metabolites, such as Methylobacterium with methylmalonic acid, highlighted microbial-driven spoilage processes. These findings provided a comprehensive understanding of quality deterioration during storage, guiding the development of enhanced preservation strategies for aquatic products.

The age, growth, and reproduction of Schizothorax pseudaksaiensis (Herzenstein, 1889), a second-level key protected aquatic species in Xinjiang, were studied using fish ecology methods, and the biological characteristics of its population are discussed. A total of 735 specimens were collected on a seasonal basis from 2021 to 2022 using cages and nets in the Turks River. The fish length ranged from 47.30 mm to 538.60 mm, and the minimum age and maximum age were 1 years old and 23 years old, respectively. The fitting correlations revealed that S. pseudaksaiensis is a uniformly growing fish. The ages at the inflection point for S. pseudaksaiensis were 22.28 (female) and 19.55 (male). The sex ratio was 0.89 (females):1 (males), and the spawning period occurred from April to July. The absolute fecundity was 55,652.01 ± 25,468.78 eggs per individual, and the relative fecundity was 25.92 ± 10.69 eggs per gram. This study provides life history trait data for S. pseudaksaiensis and has theoretical and practical importance for maintaining population dynamics and fishery ecological balance. Additionally, a basis for the protection of fishery germplasm plateau resources is provided.

In this study, a significant difference was demonstrated between the otolith increments of wild and reared Hedinichthys yarkandensis (day, 1877) . By comparing the width of the first 40 daily increments of otoliths, it was found that the otolith width of the wild H. yarkandensis was significantly wider than that of the reared H. yarkandensis. The otolith daily increment width of wild H. yarkandensis tends to increase significantly with age and then decreases slowly, while the otolith daily increment width of reared H. yarkandensis grows more steadily. This may be related to the different growing conditions of the two groups. This study investigates the relationship between the early life history of H. yarkandensis and the daily otolith increment and provides a basis for identifying fish groups and fish life histories through differences in otolith microstructure.