نتایج جستجو برای: sturgeons

تعداد نتایج: 248  

Journal: :Diversity 2023

Sturgeons are ancient and endangered species whose populations have been greatly reduced over the past few centuries due to habitat destruction overfishing for production of expensive caviar. All sturgeon listed in CITES Appendix II limit their trade; therefore, accurate identification is crucial. In this study, we performed whole-genome resequencing five species, including Kaluga (H. dauricus)...

Journal: :Ecology of Freshwater Fish 2022

Sturgeons have a complex free-embryo period extending from hatch to the initiation of exogenous feeding. Although available for some sturgeon species genus Acipenser, descriptions developmental stages free embryos Scaphirhynchus are lacking. We characterised ontogenetic development pallid (Scaphirhynchus albus) and shovelnose (S. platorynchus) through melanin plug expulsion. The rate was simila...

2008
N. S. Mugue A. E. Barmintseva S. M. Rastorguev V. N. Mugue V. A. Barmintsev

Intraspecific and interspecific nucleotide sequence variations of the mtDNA control region (D-loop) were studied with mtDNAs isolated from tissue specimens of more than 1400 sturgeons of nine species: Russian sturgeon Acipenser gueldenstaedtii , Persian sturgeon A. persicus , Siberian sturgeon A. baerii , Amur sturgeon A. schrenkii , Fringebarbel sturgeon A. nudiventris , sterlet A. ruthenus , ...

2015
Robert E. Colombo Paul S. Wills James E. Garvey ROBERT E. COLOMBO PAUL S. WILLS JAMES E. GARVEY

—During November 2002, 51 shovelnose sturgeon Scaphirhynchus platorynchus were sexed by ultrasound imaging using a portable ultrasonograph. We identified males with 96% accuracy (N 5 25) and females with 80% accuracy (N 5 25); one hermaphroditic individual was misidentified as a male. Overall, ultrasound imaging was 86% accurate. Sex in postspawned females was difficult to determine, 60% being ...

2018
Ji Chen Wei Wang Zhaohui Tian Ying Dong Tian Dong Hua Zhu Zuoyan Zhu Hongxia Hu Wei Hu

The sturgeon (Acipenseriformes) is an important farmed species because of its economical value. However, neither gene transfer nor gene editing techniques have been established in sturgeon for molecular breeding and gene functional study until now. In this study, we accomplished gene transfer and gene editing in sterlet (Acipenser ruthenus), which has the shortest sexual maturation period of st...

2003
Vadim J. Birstein Georgii Ruban Arne Ludwig Phaedra Doukakis Rob DeSalle

TheRussian sturgeon,Acipensergueldenstaedtii, is closely related to three other sturgeon species (A. persicus, A. naccarii and A. baerii), with populations in the Caspian Sea containing a cryptic lineage with an A. baerii-like mtDNA profile. Using morphological evidence (morphometrics, meristics) and additional genetic analysis (cytochrome b gene and control region sequencing), cryptic lineages...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2017
Matthew G Burgess Christopher Costello Alexa Fredston-Hermann Malin L Pinsky Steven D Gaines David Tilman Stephen Polasky

Economic incentives to harvest a species usually diminish as its abundance declines, because harvest costs increase. This prevents harvesting to extinction. A known exception can occur if consumer demand causes a declining species' harvest price to rise faster than costs. This threat may affect rare and valuable species, such as large land mammals, sturgeons, and bluefin tunas. We analyze a sim...

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