Sturgeon Fishes

Reproductive biology of middle Mississippi River shovelnose sturgeon: insights from seasonal and age variation in plasma sex steroid and calcium concentrations

“…Sturgeons are characterized by relatively late age at maturation and biennial or longer ovarian cycles (Dettlaff et al, 1993). Shovelnose sturgeon was, until recently, thought to reach sexual maturity at 5 and 7 years for males and females, respectively (Helms, 1974).…”

Spermatozoa motility in the Persian sturgeon, Acipenser persicus: effects of pH, dilution rate, ions and osmolality

“…A major part of the world's sturgeon catch (90 -92%) originates from the Caspian Sea (Dettlaff et al 1993). Stocks of sturgeons are decreasing dramatically (Conte et al 1988, Ronyai andVaradi 1995).…”

EFFECT OF TWO EGG DE-ADHESION METHODS ON REPRODUCTIVE SUCCESSES OF BELUGA Huso huso

“…The eggs are so sticky that they form clumps and coatings on spawning and incubating containers so thick that abnormal development and high mortality are likely to occur (Waltemyer, 1976;Laale, 1980;Patzner and Glechner, 1996;Riehl and Patzner, 1998;Rizzo et al, 2002;Huysentruyt and Adriaens, 2005;Feledi et al, 2011). Therefore, egg adhesion must be eliminated prior to incubation (Dettlaff et al, 1993). To deactivate the jelly layer of the fertilized sturgeon eggs, silk, mud, fuller's earth, chemicals (urea-NaCl-tannic acid) and other treatments are widely used (Conte et al, 1988, Bouchard andAloisi, 2002).…”

“…After fertilization, the fertilized eggs were washed by tannic acid (in treatment group) (tannic acid manufactured by TANAN Company, Iran) and clay suspension (in control group). The period of washing for treatment group was 1:30 min and 45 min for control group according to Dettlaff et al (1993). After washing the eggs with tannic acid, the eggs were washed with freshwater and then placed in Yushchenko incubators.…”