Title: Development of summer diets for hybrid striped bass Authors
|Gaylord, Thomas -|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 14, 2013
Publication Date: February 4, 2013
Citation: Rawles, S.D., Green, B.W., Gaylord, T.G., Barrows, F., Mcentire, M.E., Freeman, D.W. 2013. Development of summer diets for hybrid striped bass [abstract]. Book of Abstracts Mid-Continent Warm Water Fish Culture Workshop, February 4-6, 2013, Mt. Magazine State Park, AR. p.16. Technical Abstract: Temperature and ammonia increase dramatically during summer production of sunshine bass. Global temperatures are projected to increase. A factorial experiment investigated the effects of three digestible protein (DP; 33, 40, 47%), two lipid (L; 10, 18 %) and two ration levels (satiation, restricted) on growth, body composition, nutrient retention, and ammonia excretion in hybrid striped bass reared at 30.5 C up to 1 pound in size. Restricted feeding resulted in lower final weights and percent gains but higher ammonia excretion as a function of N fed/body-weight regardless of DP. Lower dietary fat (10%) resulted in lower weight gains, poorer feed conversions and higher ammonia excretion regardless of DP or ration. Weight gain was marginally higher at 47DP/18L, but FCR, and nutrient retentions were markedly poorer in the 47DP diets regardless of lipid level due to hyperphagia in these fish. At 30.5C, the 40DP/18L diet outperformed other diets in growth, lower ammonia excretion and higher nutrient retentions regardless of ration. Producers and hatcheries desiring to manage ammonia during summer production of phase II fingerlings with least compromise to production are better served to feed a 40DP/18L diet at reduced ration instead of lower protein/lipid diets. Pond production trials scheduled for the Summer of 2013 for fish up to market weight will be discussed also.