1 OKTOBER 1999
QUANTITATIVE DIETARY THREONINE REQUIREMENT OF JUVENILE STRIPED BASS MORONE SAXATILIS
B.C. Small, J.H. Soares, Jr.-1999
Journal of the World Aquaculture Society, 30(3): 319-323
Abstract:
A 10-wk feeding trial was conducted to quantify the dietary threonine requirement of juvenile striped bass Morone saxatilis. The basal diet was analyzed to contain 42% crude protein with a calculated digestible energy (DE) level of 3,200 kcal/kg. L-threonine was added to the basal diet to yield five dietary treatments of 0.61, 0.81, 1.00, 1.18, and 1.40% available threonine on a dry-matter basis. Weight gain, specific growth rate (SGR), feed conversion ratio (FCR) and apparent nitrogen utilization (ANU) were significantly (P < 0.05) affected by dietary threonine concentrations. Least-squares regression analysis of weight gain, SGR, FCR, and ANU indicated dietary threonine requirements (+/- SE) of 1.00 +/- 0.19, 0.91 +/- 0.11, 1.06 +/- 0.09 and 1.13 +/- 0.22% of dry diet, respectively. From these results, the average recommended dietary threonine requirement of juvenile striped bass is 1.03% of dry diet, 2.45% of dietary protein or 3.22 mg/kcal DE.
(Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland 20742 USA)