February 15-18, 2009 Washington State Convention Center Seattle ...

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FEEDING GOLDEN SHINER Notemigonus crysoleucas LARVAE FORMULATED DIETS
Thomas Kent*, Joseph Morris and Richard Clayton
Department of NREM
Iowa State University
Ames, Iowa 50011-3221 USA
thomask@iastate.edu
Golden shiners (Notemigonus crysoleucas) are popular baitfish for anglers as well as forage fish for other cultured fish in the
North Central Region. Since the original October 2006 USDA-APHIS VHS ruling that limited the interstate transport of specific
fish, there has been an increased demand for regionally reared baitfish. However, given this region’s short culture season
there is a need to investigate methods that produce market size, ca. 8 cm long, golden shiner fry in one culture season. The
purpose of this study was to use out-of-season spawning to obtain golden shiner fry, culture them intensively for 30 days, and
then stock them into earthen culture ponds for advanced growth.
Golden Shiner fry were obtained from broodstock that had spawned indoors on spawning mats. Eggs were removed from mats
by submerging the mats in a sodium sulfite solution for 2 minutes and then placing the eggs into 6-liter McDonald-type hatching
jars. The number of newly hatched fry were determined by volumetric displacement and subsequently stocked evenly into
100-L fiberglass tanks at random. Each pair wise comparison used three tanks per diet with the exception of one comparison
in 2007 when six tanks were used per diet. All tanks had in-tank lighting and water flow was 3 Lpm. Fry were fed at a rate of
5 grams/1,000 fry with auger feeders every 20 minutes for 22 hours per day with the exception of one diet that was hand fed
twice per day in 2008. In the two culture seasons, nine different diets were compared for their effect on fish survival; the best
performing diet in 2007 was used in 2008 comparisons. Each feeding trial was conducted for 14 days post hatch (dph), 10 dph
has been identified as the critical period for golden shiner fry survival. At the end of each 14-day test all surviving fry were
counted and survival determined.
At the completion of each 14-day trial, survival rates ranged from 0 to 16% in 2007 and 0 to 42% in 2008. The Zeigler® AP100
diet had the highest survival in one comparison with an average survival of 27.7% in 2008. All other diets had an average survival
that ranged from 0 to 8.3%, including four additional Zeigler® AP100 trials in both years. In 2007, both Zeigler® AP100
trials were found to have significantly greater survival than two diets in direct comparison (P