GROWTH AND SURVIVAL OF FIRST-FEEDING AND FINGERLING ATLANTIC STURGEON UNDER CULTURE CONDITIONS
J.W. Mohler, M. Kim King, P.R. Farrell-2000
North American Journal of Aquaculture, 62: 174-183
Abstract:
We performed rearing studies with first-feeding fry and fingerling Atlantic sturgeon Acipenser oxyrinchus oxyrinchus produced from streamside spawning of wild Hudson River adults. In all, 20,000 larvae were reared in 54-L circular tanks at initial densities of 3.7-29.6 fish/L (0.06-0.52 g/L). At the onset of exogenous feeding, diet treatments included live brine shrimp Artemia sp., frozen brine shrimp, or commercially formulated Biokyowa B-250. At the end of the 26-d study, all treatments but two had survival greater than 93%. Mean specific growth rate (SGR) was inversely proportional to fish density. Fish fed frozen brine shrimp were smaller but had equivalent survival to those fed live brine shrimp. Atlantic sturgeon converted to formulated feed with less than 25% mortality at mean total length and weight of 34.5 mm and 0.18 g in 20-26 d at initial stocking densities of 7.4 fish/L or less. A subsequent study was performed with fingerlings at densities of 0.37-2.22 g/L. These fingerlings were offered Zeigler sturgeon diet at 3% body weight daily. After 28 d, mortality ranged from 4.7% to 13.0%. Atlantic sturgeon from all treatments were similar in weight and total length. Our study showed that first-feeding Atlantic sturgeon under conditions of artificial rearing require low initial stocking densities and 20-26 d of a continuous supply of live brine shrimp to achieve a minimum size necessary for successful conversion to formulated feed. Fingerling Atlantic sturgeon that convert to formulated feed can be stocked at initial densities up to 2.22 g/L and reared for 28 d with resulting feed conversion ratios of 0.50 or better and at least 90% survival.
(U.S. Fish and Wildlife Service, Northeast Fishery Center, Post Office Box 75, Lamar, Pennsylvania 16848, USA)
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