Temperature acclimation modulates stress, immunity, and apoptosis in juvenile Siberian hybrid sturgeon during simulated transport

• Published in: Aquaculture Vol. 607; p. 742641
• Main Authors: Jiang, Hongcheng, Wang, Juguang, Wang, Zhaoding, Chen, Jiaping, Bai, Chan, Xiong, Guangquan, Cai, Wei, Cheng, Jun, Wang, Lan, Liao, Tao
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.09.2025
• Subjects: Acclimation; Acipenser baerii; apoptosis; aquaculture; blood; coagulation; complement; cortisol; gene expression regulation; glucose; hybrids; immunoglobulins; Innate immunity; juveniles; liver; lysosomes; lysozyme; spleen; Stress; Sturgeon; Temperature; transcriptomics; Transport; Sturgeon; Innate immunity; Temperature; Transport; Stress; Acclimation
• DOI: 10.1016/j.aquaculture.2025.742641
• ISSN: 0044-8486

Reasonable acclimation contributes to alleviate stress in fish transport and is one of the effective measures to improve fish welfare. Juvenile Siberian hybrid sturgeon (Acipenser baerii ♀ × A. schrenckii ♂) were used as the research subject, and low-temperature acclimation group (15 °C, T15), control group (18 °C, T18) and high-temperature acclimation group (21 °C, T21) were set up. The results showed that with the extension of transport time, the content of blood cortisol and glucose increased in all groups, with the highest stress levels observed in the T21 group. Liver oxidative indicators increased significantly in all groups, while the activity of splenic lysozyme and immunoglobulin M showed an overall downward trend, which was negatively correlated with acclimation temperature. The TUNEL analysis results showed a positive correlation between the apoptosis index of splenic cells and the acclimation temperature. A total of 1621 differentially expressed genes (DEGs) were identified by RNA-sequencing-based transcriptomic profiling, which were enriched in pathways related to innate immunity. In the T21 group, the expression levels of most DEGs related to immunoglobulin and lysosomes were significantly downregulated, while the complement and coagulation cascade pathways were activated. In addition, the JNK signaling pathway plays an important role in acclimation and transport, inducing spleen apoptosis in fish. This study contributes to understanding the changes in biochemical characteristics of juvenile Siberian hybrid sturgeons under transport stress, and accumulating important biological data for transport optimization. •Transport stress on juvenile Siberian hybrid sturgeons after different temperature acclimation was analyzed using biochemical, histological and transcriptomic methods.•Low-temperature acclimation (15 °C) can alleviate stress during transport, reduce tissue damage and cell apoptosis.•High-temperature acclimation (21 °C) increases immune suppression during transport, but more likely to activate the complement system.•Different temperature acclimation leads to changes in innate immune and apoptotic genes.