this study conducted to provide the status of parasite communities of four sturgeon species viz. acipenser stellatus , a. gueldenstaedtii , a. nudiventris , and huso huso in the southwest of the caspian sea and their histopathological effects on the examined fishes. for this purpose a total of 93 individuals of four sturgeon species were caught in two fisheries regions from the southwest of the...

histological development of digestive tract of the persian sturgeon (acipenser persicus) from hatching to fingerling size was studied using light microscope. the digestive tract of newly hatched larvae was a simple tube which continued from mouth to anus. in 7 days post hatching, digestive tract became differentiated and secretion was started smoothly, with appearance of goblet cells in epithel...

Populations of white sturgeon (WS; Acipenser transmontanus) are in decline in several parts of the United States and Canada, attributed primarily to poor recruitment caused by degradation of habitats, including pollution with contaminants such as metals. Little is known about sensitivity of WS to contaminants or metals such as copper (Cu). Here, acute (96 h) mortalities of WS early life stages ...

Enzymatic antioxidant activities (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase) and lipid peroxidation were determined in different tissues (gills, heart, digestive tract, liver, white muscle, skin, red blood cells, swimbladder) of trout (Oncorhynchus mykiss) and sturgeon (Acipenser naccarii). Total tissue antioxidant activity was, except for catalase, generally...

A phylogenetic hypothesis is presented illustrating relationships among 23 extant sturgeon species based on nucleotide data from five mitochondrial genes (cytochrome b, NADH5, control region, 16S, and 12S). The tree supports our previous hypotheses regarding relationships among species of Acipenser and Huso. The introduction of Scaphirhynchus and Pseudoscaphirhynchus to the analysis does not ch...

Scott Sturgeon has claimed to undermine the principal argument for Physicalism, in his words, the view that “actuality is exhausted by physical reality” (Sturgeon 1998, p. 410). In noting that actuality is exhausted by physical reality, the Physicalist is not claiming that all that there is in actuality are those things identified by physics. Rather the thought is that actuality is made up of a...

Sturgeon (order Acipenserformes) provide an ideal taxonomic context for examination of genome duplication events. Multiple levels of ploidy exist among these fish. In a novel microsatellite approach, data from 962 fish from 20 sturgeon species were used for analysis of ploidy in sturgeon. Allele numbers in a sample of individuals were assessed at six microsatellite loci. Species with approximat...

We report the isolation of a novel vitamin K-dependent protein from the calcified cartilage of Adriatic sturgeon (Acipenser nacarii). This 10.2-kDa secreted protein contains 16 gamma-carboxyglutamic acid (Gla) residues in its 74-residue sequence, the highest Gla percent of any known protein, and we have therefore termed it Gla-rich protein (GRP). GRP has a high charge density (36 negative+16 po...