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Submitted to: USFWS Aquaculture Drug Approval Coordination Workshop
Publication Type: Abstract Only Publication Acceptance Date: 4/15/2018 Publication Date: 6/18/2018 Citation: Chatakondi, N.G. 2018. Effects of age and dose of Salmon GnRHa (OvaRH) on the reproductive performance of channel catfish, Ictalurus punctatus to produce channel catfish x blue catfish hybrid embryos in hatcheries. USFWS Aquaculture Drug Approval Coordination Workshop. P. 15. Interpretive Summary: Technical Abstract: The present study was conducted to determine the minimum effective salmon Gonadotropin Releasing Hormone analog (sGnRHa) dose to stimulate ovulation in channel catfish, Ictalurus punctatus. Four doses of sGnRHa: 0, 10, 15 and 25 µg/Kg BW were compared with commonly used 100 µg mammalian luteinizing hormone releasing hormone analog (mLHRHa)/Kg BW to induce spawn channel catfish. Hormone-induced catfish yielded significantly higher plasma estradiol and ovulation success compared to saline-injected control fish. Ovulation ratio, relative fecundity and fry/kg with 10 µg were lower than 15 and 25 µg sGnRHa/kg treatments. To further refine the sGnRHa dose, spawning trials with 3- and 4-yr-old channel catfish were compared with either 10, 15, or 20 µg sGnRHa/kg BW. The relative fecundity (8322 eggs/kg BW) and fry production (2533 fry/kg BW) were higher in 15 µg sGnRHa/kg BW treatment. Hence, the results of this study suggest 15 µg sGnRHa/kg BW is the minimum effective dose comparable to widely used mLHRHa to induce spawn channel catfish in hybrid catfish embryo production in hatcheries. |
