By Jeff Schaeffer | AFS Co-Chief Science Editor. E-mail: [email protected]
WINNER: 2014 Best Paper, North American Journal of Aquaculture
As a practical matter, fish culturists often need to spawn fish artificially, and this is especially true of the catfish industry where hybrids of Blue Catfish Ictaluras furcatus and Channel Catfish Ictaluras punctatus are preferred for growth and disease resistance, but will not spawn naturally. Traditionally spawning has been induced by naturally sourced gonadotrophin releasing hormones (GnRH), although two synthetic analogues are licensed for use. Sylvie Quiniou and her colleagues at the U.S. Department of Agriculture–Agricultural Research Service found a new approach using a novel analogue derived from a different type of GnRH thought previously to play only a secondary role in egg development. Their method resulted in much higher ovulation rates (90.2%) than traditional treatments that usually result in lower rates (44-63%), with no differences in overall egg or fry production. We loved this paper because it has an important practical application, as well as a thoughtful discussion that provides insight into understanding fish spawning physiology. We also wonder if their work might be adapted for other culture situations where maximizing viable egg production is vital.
REFERENCE
Quiniou, S. M. A., B. Bosworth, N. Chatakondi, and D. Oberle. 2014. Evaluation of a gonadotropin releasing hormone analog of cGnRH II as a spawning aid for Channel Catfish versus analogs of mGnRH I and sGnRH III. North American Journal of Aquaculture 76(3):281-288. dx.doi. org/10.1080/15222055.2014.902889
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