Rapids habitats are critical spawning and nursery grounds for multiple Laurentian Great Lakes fishes of ecological importance such as lake sturgeon, walleye, salmonids. However, river modifications have destroyed important rapids habitat in connecting channels by modifying flow profiles removing large quantities cobble gravel that preferred substrates several fish species. The conversion to slo...

Fisheries Department, Faculty of Natural Resources, University of Guilan, Sowmeh Sara,1144, Iran ABSTRACT This study was conducted the effect of stress on blood glucose and cortisol levels in cultured great sturgeon. Blood sampling was done and then water level decreased to the half in experimental tanks. The fish were exposed in that situation and second blood sampling was taken after ...

  Sublethal toxicity effects of diazinon on the structure of some organs of great sturgeon ( Huso huso ) were investigated. Diazinon was applied at a sublethal concentration of 1.5 mg L -1 at 22±1 ºC for nine weeks as a constant bath. Tissues of liver, kidney and gills were sampled and examined histopathologically   after 1, 14, 28, 42 and 63 days post exposure to the...

this study examined the effects of implanted cortisol (to imitate chronic stress) on the hematological responses and cortisol values of female great sturgeon, huso huso, after an endoscopic operation. at the beginning of experiment, all the fish were examined using an endoscope to evaluate gonad development. then, in order to mimic chronic stress following surgery, capsules of cocoa?? butter co...

The present study examined the effects of Vitacel raw fiber on great sturgeon (Huso huso) immunocompetent cell population size including lymphocyte and neutrophil populations and lysozyme activity after oral administration of the feed and Vitacel at 1.3% of the feed for 90 days. Generally, a significant increase was seen in the neutrophil count of fish receiving Vitacel as compared to the contr...

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...

Threats such as habitat loss, invasive species, and overexploitation cause species extinctions; however, stochastic processes can accelerate extinction rates as census sizes decline. Using molecular and ecological data, we explored the influence of these processes on the demography of a candidate species under the U.S. Endangered Species Act—the Atlantic sturgeon Acipenser oxyrinchus oxyrinchus...

The raw data from study of variation of D-loop mtDNA of white sturgeon Acipenser transmontanus (Mol. Biol. Evol. 1993. 10: 326–341) was re-analyzed. Re-calculated nucleotide substitution rate (μ) was 0.782–0.939 × 10 substitutions/site/year/lineage, which was 1.4 times less than the estimate given in above-mentioned publication. The use of new μ has led to an increase in estimates of long-term ...