{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T19:29:01Z","timestamp":1793042941251,"version":"4.5.0"},"reference-count":26,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T00:00:00Z","timestamp":1786579200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Central Public-interest Scientific Institution Basal Research Fund","award":["2024TD08"],"award-info":[{"award-number":["2024TD08"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund","award":["2025QT04"],"award-info":[{"award-number":["2025QT04"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund","award":["2025ZX03"],"award-info":[{"award-number":["2025ZX03"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund","award":["2026ZL02"],"award-info":[{"award-number":["2026ZL02"]}]},{"name":"Screening, Breeding, Integrated Aquaculture Technology, Demonstration and Promotion of Marine-adapted High-quality Germplasm of Rainbow Trout in Jiangsu","award":["JCTG [2025] 26"],"award-info":[{"award-number":["JCTG [2025] 26"]}]},{"name":"Lianyungang Key Research and Development Program","award":["SF2407"],"award-info":[{"award-number":["SF2407"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biology"],"abstract":"<jats:p>This study evaluated the endpoint biochemical responses and associated physiological status of rainbow trout (Oncorhynchus mykiss) of different body sizes during salinity acclimation under varying temperature and salinity conditions. An L9 (34) orthogonal design was applied using three nominal body-size levels (100, 250, and 500 g), three temperatures (10, 15, and 20 \u00b0C), and three salinities (10, 20, and 30\u2030) over 60 days. Hepatic superoxide dismutase (SOD), alkaline phosphatase (ALP), and acid phosphatase (ACP) activities and plasma malondialdehyde (MDA), urea nitrogen (BUN), ammonia, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured. For inferential analysis, the three fish sampled from each tank were averaged to obtain one tank-level value, yielding 18 tank-level observations. Tank-level main-effects analysis showed that body size was significantly associated with ALP, ACP, MDA, BUN, ammonia, ALT, and AST. Temperature was significantly associated with SOD, ACP, MDA, BUN, and AST, whereas salinity was significantly associated with MDA, ALT, and AST. MDA and AST were the only endpoints associated with all three factors. The biochemical responses were pathway-specific rather than uniformly directional across treatment combinations. Because interactions could not be independently estimated in the L9 design, the identified main effects should be interpreted as orthogonal screening associations. Overall, body-size class was associated with the broadest range of endpoints and should be incorporated into future experimental assessments of rainbow trout within the tested salinity range of 10\u201330\u2030.<\/jats:p>","DOI":"10.3390\/biology15161383","type":"journal-article","created":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T09:31:09Z","timestamp":1786613469000},"page":"1383","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Physiological and Biochemical Responses of Rainbow Trout (Oncorhynchus mykiss) of Different Body Sizes Under Varying Temperature and Salinity Conditions: An L9 Orthogonal Design"],"prefix":"10.3390","volume":"15","author":[{"given":"Jiahe","family":"Guo","sequence":"first","affiliation":[{"name":"National Engineering Research Center for Marine Aquaculture, Zhejiang Ocean University, Zhoushan 316022, China"},{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuanhao","family":"Ren","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changjian","family":"Li","sequence":"additional","affiliation":[{"name":"Lianyungang Ocean and Fishery Development Promotion Center, Lianyungang 222000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9395-3119","authenticated-orcid":false,"given":"Hanfeng","family":"Zheng","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6556-4658","authenticated-orcid":false,"given":"Zhongquan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2318-9534","authenticated-orcid":false,"given":"Fengyuan","family":"Shen","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"Qin","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Na","family":"Ying","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3482-2187","authenticated-orcid":false,"given":"Siping","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tingting","family":"Lin","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2273-8367","authenticated-orcid":false,"given":"Yanming","family":"Sui","sequence":"additional","affiliation":[{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"},{"name":"Jiangsu Key Laboratory for Exploration and Utilization of Marine Wetland Biological Resources, Yancheng Institute of Technology, Yancheng 224051, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lei","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China"},{"name":"Jiangsu (Marine) Salmon and Trout Science and Technology Innovation Center, Yellow Sea Laboratory for Blue Seed Industry, Yancheng 224000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,13]]},"reference":[{"key":"ref_1","unstructured":"Food and Agriculture Organization of the United Nations (2026, July 10). Cultured Aquatic Species Information Programme: Oncorhynchus mykiss (Walbaum, 1792). Available online: https:\/\/www.fao.org\/fishery\/culturedspecies\/oncorhynchus_mykiss\/en."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1007\/s42995-022-00141-2","article-title":"Mapping the potential for offshore aquaculture of salmonids in the Yellow Sea","volume":"4","author":"Yu","year":"2022","journal-title":"Mar. Life Sci. Technol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2083","DOI":"10.1139\/f91-247","article-title":"Effects of salinity on growth, metabolism, and ion regulation in juvenile rainbow and steelhead trout (Oncorhynchus mykiss) and fall Chinook salmon (Oncorhynchus tshawytscha)","volume":"48","author":"Morgan","year":"1991","journal-title":"Can. J. Fish. Aquat. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2369","DOI":"10.1111\/are.14580","article-title":"Growth, osmoregulation and energy budget of rainbow and steelhead trout under different salinity acclimation methods and the best transition size of steelhead trout","volume":"51","author":"Xiong","year":"2020","journal-title":"Aquac. Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1007\/s00360-021-01363-z","article-title":"Effects of different temperatures on seawater acclimation in rainbow trout Oncorhynchus mykiss: Osmoregulation and branchial phospholipid fatty acid composition","volume":"191","author":"Ge","year":"2021","journal-title":"J. Comp. Physiol. B"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Ge, J., Zhou, Y., Huang, M., Gao, Q., Dong, Y., and Dong, S. (2021). Effects of constant and diel cyclic temperatures on the liver and intestinal phospholipid fatty acid composition in rainbow trout Oncorhynchus mykiss during seawater acclimation. BMC Zool., 6.","DOI":"10.1186\/s40850-021-00086-6"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"740874","DOI":"10.1016\/j.aquaculture.2024.740874","article-title":"Influence of salinity on rainbow trout (Oncorhynchus mykiss) smolt development and postsmolt performance","volume":"587","author":"Balseiro","year":"2024","journal-title":"Aquaculture"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"coy061","DOI":"10.1093\/conphys\/coy061","article-title":"Seawater acclimation affects cardiac output and adrenergic control of blood pressure in rainbow trout (Oncorhynchus mykiss)\u2014Implications for salinity variations now and in the future","volume":"6","author":"Sundell","year":"2018","journal-title":"Conserv. Physiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"R1385","DOI":"10.1152\/ajpregu.00443.2004","article-title":"Salinity acclimation affects the somatotropic axis in rainbow trout","volume":"288","author":"Shepherd","year":"2005","journal-title":"Am. J. Physiol. Regul. Integr. Comp. Physiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1016\/S0990-7440(98)89005-0","article-title":"Effects of feeding level and water temperature on growth, nutrient and energy utilization and waste outputs of rainbow trout (Oncorhynchus mykiss)","volume":"11","author":"Azevedo","year":"1998","journal-title":"Aquat. Living Resour."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"102928","DOI":"10.1016\/j.jtherbio.2021.102928","article-title":"Effects of temperature, dissolved oxygen, and their interaction on the growth performance and condition of rainbow trout (Oncorhynchus mykiss)","volume":"98","author":"Jiang","year":"2021","journal-title":"J. Therm. Biol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"113949","DOI":"10.1016\/j.ecoenv.2022.113949","article-title":"Physiological responses to heat stress in the liver of rainbow trout (Oncorhynchus mykiss) revealed by UPLC-QTOF-MS metabolomics and biochemical assays","volume":"242","author":"Li","year":"2022","journal-title":"Ecotoxicol. Environ. Saf."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"215","DOI":"10.12717\/DR.2020.24.3.215","article-title":"Differential seawater adaptability in three different sizes of under-yearling steelhead trout","volume":"24","author":"Lee","year":"2020","journal-title":"Dev. Reprod."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1016\/0044-8486(92)90216-8","article-title":"Importance of body size for acclimation of underyearling Atlantic salmon parr (Salmo salar L.) to seawater","volume":"104","author":"Bjerknes","year":"1992","journal-title":"Aquaculture"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/0044-8486(88)90263-3","article-title":"Development of seawater adaptation in juvenile steelhead trout (Salmo gairdneri) and domesticated rainbow trout (Salmo gairdneri)\u2014Effects of size, temperature and photoperiod","volume":"71","author":"Johnsson","year":"1988","journal-title":"Aquaculture"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1007\/s10695-006-9105-6","article-title":"Cellular responses to temperature stress in steelhead trout (Oncorhynchus mykiss) parr with different rearing histories","volume":"32","author":"Werner","year":"2006","journal-title":"Fish Physiol. Biochem."},{"key":"ref_17","first-page":"135","article-title":"Levels of antioxidant enzyme activities in cultured rainbow trout (Oncorhynchus mykiss) fed with different diet compositions","volume":"41","year":"2021","journal-title":"Bull. Eur. Assoc. Fish Pathol."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Magnoni, L.J., Novais, S.C., Eding, E., Leguen, I., Lemos, M.F.L., Oz\u00f3rio, R.O.A., Geurden, I., Prunet, P., and Schrama, J.W. (2019). Acute stress and an electrolyte-imbalanced diet, but not chronic hypoxia, increase oxidative stress and hamper innate immune status in a rainbow trout (Oncorhynchus mykiss) isogenic line. Front. Physiol., 10.","DOI":"10.3389\/fphys.2019.00453"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"695","DOI":"10.1016\/S1096-4959(01)00370-0","article-title":"Stimulation of non-specific immune functions in seawater-acclimated rainbow trout, Oncorhynchus mykiss, with reference to the role of growth hormone","volume":"129","author":"Yada","year":"2001","journal-title":"Comp. Biochem. Physiol. Part B Biochem. Mol. Biol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"103499","DOI":"10.1016\/j.dci.2019.103499","article-title":"Seasonal changes of hydrolytic enzyme activities in the skin mucus of rainbow trout, Oncorhynchus mykiss, at different body sizes","volume":"103","author":"Abolfathi","year":"2020","journal-title":"Dev. Comp. Immunol."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Han, B., Meng, Y., Tian, H., Li, C., Li, Y., Gongbao, C., Fan, W., and Ma, R. (2022). Effects of acute hypoxic stress on physiological and hepatic metabolic responses of triploid rainbow trout (Oncorhynchus mykiss). Front. Physiol., 13.","DOI":"10.3389\/fphys.2022.921709"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1674","DOI":"10.1071\/MF18029","article-title":"Effects of heat stress on biochemical parameters and heat shock protein family A (Hsp70) member 5 (HSPA5) mRNA expression in rainbow trout (Oncorhynchus mykiss)","volume":"69","author":"Xia","year":"2018","journal-title":"Mar. Freshw. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3557","DOI":"10.1242\/jeb.057802","article-title":"A nose-to-nose comparison of the physiological and molecular responses of rainbow trout to high environmental ammonia in seawater versus freshwater","volume":"214","author":"Wood","year":"2011","journal-title":"J. Exp. Biol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"499","DOI":"10.1016\/j.aquaculture.2004.06.020","article-title":"Excretion of ammonia and urea by phylogenetically diverse fish species in low salinities","volume":"238","author":"Altinok","year":"2004","journal-title":"Aquaculture"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1152\/physiolgenomics.00061.2007","article-title":"Ammonia excretion in rainbow trout (Oncorhynchus mykiss): Evidence for Rh glycoprotein and H+-ATPase involvement","volume":"31","author":"Nawata","year":"2007","journal-title":"Physiol. Genom."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"jeb249654","DOI":"10.1242\/jeb.249654","article-title":"Accounting for the role of the gastrointestinal tract in the ammonia and urea nitrogen dynamics of freshwater rainbow trout on long-term satiation feeding","volume":"228","author":"Wood","year":"2025","journal-title":"J. Exp. Biol."}],"container-title":["Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-7737\/15\/16\/1383\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T09:49:23Z","timestamp":1786614563000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-7737\/15\/16\/1383"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,13]]},"references-count":26,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["biology15161383"],"URL":"https:\/\/doi.org\/10.3390\/biology15161383","relation":{},"ISSN":["2079-7737"],"issn-type":[{"value":"2079-7737","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,13]]}}}