The effect of GnRH (ovafact) on process of sexual maturation in farmed stellate sturgeon (Acipenser stellatus) brood stock
Subject Areas : New Technologies in Aquaculture Development
Keywords: Hormone, Stress, GnRH, Keywords: Stellate sturgeon brooders, Cortisole, Ovulation, Spermation,
Abstract :
Abstract Stellate sturgeon (Acipenser stellatus) is one of the important commercial sturgeon fishes of Caspian Sea. In order to study the indices of stress hormones in culture brood stock during spawning period and their relation to success or failure in artificial reproduction of these fishes, blood sample were taken from 11 cultured eight years old brood stock (which included 5 female and 6 male). The study was carried out at sturgeon research of Dr. Dadman in spring of 2006-2007. After analyzing the morphological and physiological characteristics of brood stocks, induced reproduction was carried out by injection of GnRH hormone (female were injected twice with total dose of 10µg/kg. The interval between the first and second injection was 12 hrs. The males were injected once using a 15 µg/kg dose. After the injection, two blood samples from male (0 hrs and 6 hrs after injection) and three blood samples from female (0 hrs/12 hrs and 24 hrs after the injection) were taken to analyze the biochemical and hormonal parameters. Result obtained show that the concentration of cortisole levels (187±30.89 Ng/kg) 24hrs after injection in female brood stock in which ovulation had occurred compared with the once without ovulation showed a significant relationship. On the other hand the concentration glucose (96.66±9.33mg/dl) 24hrs the injection in male brood stock in which spermiation had occurred compared with the once without spermiation showed a significant relationship. we can conclude that there was a significant difference in concentration of cortisole and glucose in female and male brood stock, respectively which have been successfully induced to spawn in comparison to once in which induction of spawning has not been successful.
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