Mandarin fish(Siniperca scherzeri) has high market prices and significant market potential in China because of its highquality meat and high nutritional value. However, due to the limited scale of aquaculture, meeting...Mandarin fish(Siniperca scherzeri) has high market prices and significant market potential in China because of its highquality meat and high nutritional value. However, due to the limited scale of aquaculture, meeting the market demand is difficult, making the effective development of the aquaculture potential of mandarin fish an important challenge for the industry. In this study, a 30-d breeding experiment was conducted on mandarin fish larvae under three photoperiod conditions: G1 8 h light:16 h dark(8L:16D), G2 12 h light:12 h dark(12L:12D), and G3 16 h light:8 h dark(16L:8D). The results showed that the G2 group exhibited the best growth performance and development status, with final body weights, weight gain rates, and specific growth rates all higher than those of the other two groups(P < 0.05). Observations of sections from each group revealed that the intestinal villi length and muscle thickness of the G2 group were significantly greater than those of the other two groups(P < 0.05). The G2 group inhibited the transcriptional activation of key circadian rhythm genes, including nr1d2a, nr1d1 and per1, while upregulating the expression of BMAL1 in S. scherzeri.The activation of both the insulin signalling pathway and the Fox O signalling pathway enhanced the efficient secretion of insulin, which subsequently played a critical role in regulating fatty acid metabolism. This active fatty acid metabolism provided an optimal energy supply, ensuring that other nutrients were fully utilized during the growth and development process while minimizing unnecessary nutrient loss. Consequently, this mechanism effectively promoted the overall growth and development of S. scherzeri. This study was the first to elucidate the transcriptomic expression patterns of S. scherzeri under varying photoperiod conditions. In response to the cyclic alternation of day and night, S. scherzeri regulated their metabolic levels and the transcriptional activation of downstream target genes via insulin signalling.展开更多
To improve understanding of coastal seagrass bed habitats in China,this study investigated seagrass distribution patterns and analyzed water column and sediment parameters of seagrass bed ecosystems on Guanglu,Zhangzi...To improve understanding of coastal seagrass bed habitats in China,this study investigated seagrass distribution patterns and analyzed water column and sediment parameters of seagrass bed ecosystems on Guanglu,Zhangzi,and Haiyang Islands in Changhai County,Dalian City,during August 2022.The findings revealed that seagrass beds were predominantly composed of Zostera marina,Zostera japonica,and Zostera caespitosa,with Zostera marina as the dominant species.All seagrass species exhibited patchy spatial distributions,potentially linked to localized environmental stressors.Seagrass beds on Zhangzi Island exhibited high suspended particulate matter,while those on Haiyang Island showed elevated sediment chemical constituents and low dissolved oxygen in the water column.Among the three sites,Zhangzi Island had the lowest macroalgal coverage,shoot density,and epiphytic biomass.Seagrass beds on Haiyang Island displayed higher epiphytic biomass than the other two islands.Conversely,seagrass beds on Guanglu Island were characterized by lower shoot height and benthic biomass.Although ecological assessment indices classified all three island seagrass beds as grade I(currently stable),persistent anthropogenic disturbances were identified as drivers of gradual degradation,potentially threatening future stability.These findings highlight site-specific habitat characteristics and underscore the importance of targeted conservation strategies.This research provides crucial baseline data for the conservation and management of coastal seagrass beds.展开更多
基金The Science and Technology Plan of Dalian under contract Nos 2023RO058 and 2022RQ060the Liaoning Province Natural Science Planning Fund Project under contract No. 2022-BS-273+1 种基金the Liaoning Provincial Department of Education Basic Research Project under contract No. LJKQZ20222357the Discipline Construction Funding for Marine Science Subject of Dalian Ocean University。
文摘Mandarin fish(Siniperca scherzeri) has high market prices and significant market potential in China because of its highquality meat and high nutritional value. However, due to the limited scale of aquaculture, meeting the market demand is difficult, making the effective development of the aquaculture potential of mandarin fish an important challenge for the industry. In this study, a 30-d breeding experiment was conducted on mandarin fish larvae under three photoperiod conditions: G1 8 h light:16 h dark(8L:16D), G2 12 h light:12 h dark(12L:12D), and G3 16 h light:8 h dark(16L:8D). The results showed that the G2 group exhibited the best growth performance and development status, with final body weights, weight gain rates, and specific growth rates all higher than those of the other two groups(P < 0.05). Observations of sections from each group revealed that the intestinal villi length and muscle thickness of the G2 group were significantly greater than those of the other two groups(P < 0.05). The G2 group inhibited the transcriptional activation of key circadian rhythm genes, including nr1d2a, nr1d1 and per1, while upregulating the expression of BMAL1 in S. scherzeri.The activation of both the insulin signalling pathway and the Fox O signalling pathway enhanced the efficient secretion of insulin, which subsequently played a critical role in regulating fatty acid metabolism. This active fatty acid metabolism provided an optimal energy supply, ensuring that other nutrients were fully utilized during the growth and development process while minimizing unnecessary nutrient loss. Consequently, this mechanism effectively promoted the overall growth and development of S. scherzeri. This study was the first to elucidate the transcriptomic expression patterns of S. scherzeri under varying photoperiod conditions. In response to the cyclic alternation of day and night, S. scherzeri regulated their metabolic levels and the transcriptional activation of downstream target genes via insulin signalling.
基金Dalian Science and Technology Innovation Fund under contract No.2024JJ11PT007Dalian Science and Technology Program for Innovation Talents of Dalian under contract No.2022RJ06+2 种基金Science and Technology Program of Liaoning Province under contract Nos.2022JH2/101300222 and 2022JH2/101300183Scientific Research Project of Education Department of Liaoning Province under contract No.LJ232410158056Research Funds for Undergraduate Universities of Liaoning Province under contract No.2024JBPTZ001。
文摘To improve understanding of coastal seagrass bed habitats in China,this study investigated seagrass distribution patterns and analyzed water column and sediment parameters of seagrass bed ecosystems on Guanglu,Zhangzi,and Haiyang Islands in Changhai County,Dalian City,during August 2022.The findings revealed that seagrass beds were predominantly composed of Zostera marina,Zostera japonica,and Zostera caespitosa,with Zostera marina as the dominant species.All seagrass species exhibited patchy spatial distributions,potentially linked to localized environmental stressors.Seagrass beds on Zhangzi Island exhibited high suspended particulate matter,while those on Haiyang Island showed elevated sediment chemical constituents and low dissolved oxygen in the water column.Among the three sites,Zhangzi Island had the lowest macroalgal coverage,shoot density,and epiphytic biomass.Seagrass beds on Haiyang Island displayed higher epiphytic biomass than the other two islands.Conversely,seagrass beds on Guanglu Island were characterized by lower shoot height and benthic biomass.Although ecological assessment indices classified all three island seagrass beds as grade I(currently stable),persistent anthropogenic disturbances were identified as drivers of gradual degradation,potentially threatening future stability.These findings highlight site-specific habitat characteristics and underscore the importance of targeted conservation strategies.This research provides crucial baseline data for the conservation and management of coastal seagrass beds.
