نتایج جستجو برای: sturgeons
تعداد نتایج: 248 فیلتر نتایج به سال:
Primordial germ cells (PGCs) arise elsewhere in the embryo and migrate into developing gonadal ridges during embryonic development. In several model animals, formation and migration patterns of PGCs have been studied, and it is known that these patterns vary. Sturgeons (genus Acipenser) have great potential for comparative and evolutionary studies of development. Sturgeons belong to the super c...
Abstract This study aims to reconstruct the historical spatiotemporal distribution of anadromous sturgeons, Acipenser sturio and A. oxyrinchus, in NW-Europe (especially Rhine, Meuse, Scheldt, Ems rivers, North Sea), light evaluating possibilities for their reintroduction. It is based on fisheries data from 14th–twentieth century, consisting > 5000 records sturgeon landings sales (c. 40,000 s...
Acipenseriformes are composed of 25 sturgeon species and two paddlefish species distributed exclusively in the northern hemisphere. The Danube River and the Black Sea were originally inhabited by six sturgeon species but two are extinct and only four are still reproducing currently in the Lower Danube: Huso huso, Acipenser stellatus, A. gueldenstaedtii and A. ruthenus. Sturgeon species hybridiz...
The conservation status of sturgeon species is highly alarming. Six the European Acipenser are critically endangered. Several studies developed in last decades have analysed distribution sturgeons Iberian Peninsula, questioning possibility native character some there, with a special focus on Adriatic sturgeon, A. naccarii. We review available knowledge sturgeons, order to ascertain their native...
since sturgeons have no external sexual dimorphism and there are no external markers to determine sex, internal examination of the gonads should be used to sex identification. the present study describes the biopsy method and histological observations of the gonads of great sturgeon (huso huso) in both sexes at different age classes. sex and maturity stages of 226 great sturgeons were identifie...
BACKGROUND: Paddlefish and sturgeons (Acipenseriformes) collectively constitute one of the most imperiled groups of fishes in North America. Populations were over-exploited for meat and caviar in the early 20th century (Tower 1908, Stockard 1908, Saffron 2002) and are impacted today by continued harvesting, habitat degradation, and habitat loss (Williamson 2003). Some instances of entrainment h...
Conventional sperm analysis (i.e., motility and fertility) has been used to evaluate sperm quality. Understanding the quality of sperm on the molecular level in the sturgeons, Acipenser baerii and A. schrenckii, is essential for the improvement of the conservation of genetic resources and farming performance. In this study, we used the iTRAQ proteomics approach to perform proteomic profiling of...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید