Bruce were these guys using your stuff ?
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North American Journal of Aquaculture 2009; 71: 52-58
TECHNICAL NOTE
Production Methods for Food-Sized Bluegills
Charles E. Hicks*
Cooperative Research, Lincoln University, Foster Hall, 904 Chestnut Street, Jefferson City, Missouri 65101, USA
Mark R. Ellersieck
University of Missouri, 307E Middlebush Hall, Columbia, Missouri 65211-6100, USA
Cindy J. Borgwordt
Cooperative Research, Lincoln University, Foster Hall, 904 Chestnut Street, Jefferson City, Missouri 65101, USA
Abstract
Growth of selected crosses (P1♀ × F1♂, F1♀ × P1♂, and F1♀ × F1♂) of Lincoln University bluegill stocks were evaluated. The purpose was to test the commercial potential for reaching marketable size (227–340 g) within 2 years in an
indoor water-recycle system and grow-out in ponds. Pond hatched young-of-year bluegill were reared in a 12-tank (719 L/tank) indoor water-recycle system. Fish were fed to satiation three times daily. Fish were weighed and measured for total length (TL), for a 120-d growth trial. Initial mean fish weight and TL were 28.0 ± 15.8 g and 106 ± 16 mm, respectively. Final mean weight was 119.4 ± 54.9 g, and mean TL was 161 ± 19 mm. Crosses were significantly different (P ≤ 0.05). Initial female weight averaged 82.1 ± 32.5 g, and male weight averaged 158.6 ± 45.5 g. Feed conversion ratio was 1.26, and survival was 99.4%. Specific growth rate (SGR) averaged 1.21%/d with a mean length increase of 0.5 mm/d. Fish were then marked by specific crosses with colored visible implant elastromer tags.
Fish were stocked in four 0.04-ha ponds (N = 600 fish/pond; density = 15,000 fish/ha) for 129 d. Final mean weight of fish in the pond study was 228.3 ± 71.7 g; mean TL was 200 ± 15 mm. Crosses were not significantly different from each other (P > 0.05). Sexual dimorphism was more pronounced after pond rearing; females averaged 175.4 ± 41.7 g and males averaged 284.0 ± 54.4 g. Results indicate bluegill grown in indoor recycle systems may reach target weights of 227–340 g within 2 years with the use of out-of-season spawning and selective breeding. Forty-eight percent reached or exceeded the minimum target weight (227–340 grams).
This study also suggests that removing females could increase the number of fish reaching target weight by 33%.