The Caspian seal (Pusa caspica) has declined by more than 90% since 1900 and is listed as endangered by IUCN. We made the first quantitative assessment of Caspian seal by-catch mortality in fisheries in the north Caspian Sea by conducting semi-structured interviews in fishing communities along the coasts of Russia (Kalmykia, Dagestan), Kazakhstan and Turkmenistan. We recorded a documented minim...

concentration levels of 16 polycyclic aromatic hydrocarbons (pahs) consisting of naphthalene, acenaphthylene, acenaphthene, fluorine, phenantherene, anthracene, fluor?anthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)p?yrene, dibenzo(a,h)ant?hracene, indeno(1,2,3-cd) pyrene and benzo(g,h,i)perylene were measured in water and sediment samples coll...

This study was carried out in a completely randomized design 3×3×4 factorial arrangement in three periods of rearing in spring 1997. Density of 300 larvae was assigned for each oval tank with 0.1m2 surface area, 30cm deep, a volume of 20lit and 0.25 lit/min of water flow per minute at Shahid Rajaie fish breeding and culture center in Sari, north of Iran. The fries were divided into ...

persian sturgeon (acipenser persicus) is a valuable fish caught in the caspian sea. in this study, effect of frying, the most common cooking methods on nutritional properties of the persian sturgeon fillet were investigated. the raw and fried samples were analyzed for amino acid composition, protein and fat content, in vitro digestibility and nutritional parameters. the results showed that the ...

The micropyle number in the ova of sturgeon species from the South Caspian Sea was investigated. The study was conducted on female broodfishes of three species of sturgeon (Persian sturgeon Acipenser persicus, Stetates sturgeon A. stellatus and great sturgeon Huso huso) included 44 Persian sturgeon, 13 stellate sturgeon and 8 great sturgeon specimens. Fifty eggs were randomly collected from eac...

The most utilized method to measure swimming performance of fishes has been the critical swimming speed (UCrit) test. In this test, the fish is forced to swim against an incrementally increasing flow of water until fatigue. Before the water velocity is increased, the fish swims at the water velocity for a specific, pre-arranged time interval. The magnitude of the velocity increments and the tim...

Progeny from six different spawns of white sturgeon broodstock were monitored for 20 months in a commercial white sturgeon hatchery for occurrence of outbreaks of white sturgeon iridovirus Ž . Ž . WSIV and white sturgeon herpesvirus-2 WSHV-2 . Five WSIV but no WSHV-2 outbreaks occurred during the study period. Signs of WSIV were restricted to tanks from a single spawn Ž . each time except for o...

Basal ray-finned fishes possess a heterocercal tail in which the dorsal lobe containing the extension of the vertebral column is longer than the ventral lobe. Clarifying the function of the heterocercal tail has proved elusive because of the difficulty of measuring the direction of force produced relative to body position in the aquatic medium. We measured the direction of force produced by the...

in this study, the cdna growth hormone (cgh) of the belugasturgeon (husohuso) and russian sturgeon (acipensergueldenstaedtii) were cloned and sequenced, and phylogenetic relationships were examined using nucleic acid and amino acid sequences. the nucleotide sequence of the beluga gh has an open reading frame of 645 nucleotides encoding a protein 214 amino acid residues. the signal peptide cleav...

Sturgeon are fish that considered living fossils. Their ancestors date back over 200 million years, to the same time as dinosaurs. These can grow taller than humans (over 2 m), weigh 160 kg, and live long humans. species have special adaptations, such a vacuum-like mouth body armor called scutes. There 27 of sturgeon worldwide. Two species, green white sturgeon, native California, USA, some lar...