The aim of this study was to investigate the utilization of essential fatty acids by Chinese sturgeon Acipenser sinensis during gonadal development and juvenile growth stages. Muscles and eggs from stages II to V control-bred broodfish were sampled to analyze whether fatty acids were transferred from the muscle to the gonads. Fatty acids in the muscles of broodstock females were relatively stable from stages II to IV, whereas the total PUFA content, as well as the ratio of n-3/n-6 PUFA and DHA/EPA in stage V gonads were significantly higher than in the corresponding muscle tissue. Naturally spawned eggs collected from the Yangtze spawning area were hatched and cultured in the same environment and with the same feeding strategy as the closed-cycle controll-bred eggs and juveniles. However, the relative content of C18:1n-9 and C22:6n-3 in the naturally spawned eggs was significantly higher. Naturally spawned juvenile n-3 PUFA was also significantly higher than in control-bred juveniles. These findings illustrated that PUFA, especially the DHA, EPA and ARA, are of great absorption and utilization in gonadal development and juvenile growth of Chinese sturgeon. U.S.

With the growing sophistication of cloning technology, rescuing cell resources is of great significance for the protection of endangered animals. The Yangtze sturgeon (Acipenser dabryanus), one of the three Acipenseriformes species in the Yangtze River, is critically endangered. Natural reproduction of the Yangtze sturgeon has not been detected since 2000. Less than 20 wild individuals are kept in husbandry, and all are too old to breed. Therefore, it is urgent to rescue the genetic resources of every wild Yangtze sturgeon. Here, we isolated and preserved viable cells from critically endangered postmortem Yangtze sturgeon for the first time. Attempts to rescue and preserve cell resources were carried out from 8 tissues, brain, kidney, gonad, fin, liver, skin, spleen, and muscle of an over 35-year-old female wild Yangtze sturgeon between 11 and 14 hours after death at 19.8°C in an outdoor concrete pond, and only muscle tissue cells could be successfully subcultured and preserved. Furthermore, the cultured cells showed high post-thaw cell viability and normal growth with a population doubling time of 52.98 h. Moreover, they were fibronectin- and desmin-positive, characterizing them as fibroblastic confirmed muscle cells with fibroblastic properties and myogenic origin. Tests for microbial contamination of the cell lines were negative. Chromosome analysis demonstrated that muscle cells possess a modal polyploid chromosome number of 264. The mitochondrial sequence data of COI genes and 12S rRNA confirmed that the developed cell line originated from A. dabryanus. Furthermore, transfection results indicate that muscle cells could be used for gene manipulation and functional studies. These results suggest that viable muscle cells could also be successfully isolated and cryopreserved from the wild Yangtze sturgeon in a short time after death. This report is not only of great significance for the germplasm rescue of critically endangered Yangtze sturgeon but also provides some scientific reference for the germplasm preservation of other endangered fish.

With the growing sophistication of cloning technology, rescuing cell resources is of great significance for the protection of endangered animals. The Yangtze sturgeon (Acipenser dabryanus), one of the three Acipenseriformes species in the Yangtze River, is critically endangered. Natural reproduction of the Yangtze sturgeon has not been detected since 2000. Less than 20 wild individuals are kept in husbandry and all are too old to breed. Therefore, it is urgently to rescue the genetic resources of every wild Yangtze sturgeon. Here, we isolated and preserved viable cells from the post-mortem critically endangered Yangtze Sturgeon for the first time. Attempt of rescuing and preserving cell resources were carried out from 8 tissues, brain, kidney, heart, fin, liver, skin, spleen and muscle of over-35-years-old female wild Yangtze sturgeon between 11 and 14 hours after death at 19.8℃ in outdoor concrete pond, and only muscle tissue cells could be successfully sub-cultured and preserved. Furthermore, the cultured cells were assessed by population doubling time, immunofluorescence analysis, microorganism detection, karyotyping and origin identification, and no abnormality was observed in the morphology, structure, growth and ploidy. These results suggest that viable cells could also be successfully isolated and cryopreserved from the wild Yangtze sturgeon in a short time after death, and muscle tissues had more potential to separate living cells than other tissues. This report is not only of great significance to the germplasm rescue of critically endangered Yangtze sturgeon, but also provides some scientific reference for the germplasm preservation of other endangered fish.