Page 141 - 《水产学报》2025年第6期

王谱渊，等 水产学报, 2025, 49(6): 069111

Comparative analysis of osmoregulatory capacity in freshwater-cultured
juveniles of Acipenser sinensis and A. dabryanus

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WANG Puyuan , LENG Xiaoqian , REN Feixiang , ZHONG Jia , CHENG Peilin ,
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ZHANG Lining , QIAO Xinmei , DU Hao 1,2*
1. College of Marine Living Resource Sciences and Management, Shanghai Ocean University, Shanghai 201306, China;
2. Key Laboratory of Freshwater Biodiversity Conservation, Ministry of Agriculture and Rural Affairs,
Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China;
3. Zhejiang Mariculture Research Institute, Wenzhou 325700, China
Abstract: Acipenser sinensis and Acipenser dabryanus are flagship species in the Yangtze River Basin. Due to the severe
decline of natural resources, establishing artificial conservation populations and breeding and releasing them have become key
measures for repairing wild populations. A. sinensis and A. dabryanus belong to the sisters species in the evolutionary relation-
ship. As an important feature of species differentiation, the difference in natural life history suggests that there may be a huge
difference in the osmotic pressure regulation mechanism of salinity adaptation between the two at the juvenile stage. The
migratory habits of sturgeons give them unique living habits in rivers and oceans. Studying the osmotic regulation of sturgeons
is of great significance for understanding their physiological characteristics and protecting this rare species.In order to investig-
ate the difference of osmotic adjustment ability of juvenile A. sinensis and A. dabryanus in adapting to seawater. Freshwater
cultured juvenile A. sinensis and A. dabryanus as research subjects, and the seawater domestication experiment was carried out
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by continuous salt elevation. The osmotic pressure, Na content, cortisol, gill Na /K -ATPase (NKA) activity and gill tissue
structure changes of juvenile A. sinensis and A. dabryanus were compared and analyzed at 0, 9, 19, 28 during acculturation. The
results of serum indexes showed that the serum osmotic pressure of juvenile A. sinensis and A. dabryanus increased with the
increase of environmental salinity, but the serum osmotic pressure of A. sinensis was significantly lower than that of A. dabry-
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anus at high salinity. Similarly, the serum Na content of A. sinensis was significantly lower than that of A. dabryanus. The
serum cortisol content of juvenile A. sinensis increased significantly, while that of A. dabryanus had no significant change. Gill
NKA test results showed that the gill NKA activity of A. sinensis increased significantly at high salinity, and that of A. dabry-
anus increased at 9 ppt, but decreased significantly at high salinity. H&E staining of gill tissue showed that the diameter and
number of secreting chlorine cells of juvenile Chinese and A. dabryanus increased significantly with the increase of salinity.
However, under the condition of hyperosmosis, the gill filaments of juvenile Yangtze River sturgeon showed complete loss of
structure, and the flat epithelial cells of gill lamella showed different degrees of shedding or separation. The results showed that
juvenile A. sinensis had strong osmotic regulation and adaptability in a high salinity environment. The body could enhance gill
filament NKA activity through the regulation of hormone levels, stimulate the increase in the diameter and number of gill epi-
thelial chlorine cells, and achieve ion exhalation and osmotic pressure balance in a high salinity environment. However, the
salinity adaptation range of juvenile A. dabryanus is poor and when the salinity exceeds a certain tolerance range, it will cause
irreversible effects on the organizational structure. The findings provided basic data for the exploration of land-sea relay protec-
tion model of A. sinensis.
Key words: Acipenser sinensis; Acipenser dabryanus; cultured in fresh water; osmotic regulation
Corresponding authors: LENG Xiaoqian. E-mail: lengxiaoqian@yfi.ac.cn;
DU Hao. E-mail: duhao@yfi.ac.cn
Funding projects: National Key R & D Program of China (2021YFD1200305, 2021YFD1200304); National Natural Science
Foundation of China (32202940)

中国水产学会主办 sponsored by China Society of Fisheries https://www.china-fishery.cn
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