Effect of Dietary Vitamins A and E on Whole Body and Liver Vitamin Concentrations in Rainbow Trout (Onchorhynchus mykiss)
IAAAM Archive
Ellen S. Dierenfeld1, PhD, CNS; Peter P. Hoppe2, Dr. Med Vet; Franz-Josef Schoener2, PhD
1Department of Nutrition, Wildlife Conservation Society, Bronx, NY, USA; 2BASF Nutrition Research Station, Queich, Germany

Abstract

Rainbow trout (Onchorhynchus mykiss; n = 16-24 individuals per tank) were maintained on pelleted diets, in a closed recirculating water system at 13-15°C. Experimental diets contained either 22,000 or 220,000 IU vitamin A per kg dry matter (DM), and vitamin E concentrations of 18, 180, or 1800 IU/kg DM (n = 3 replicates per dietary treatment). Intake (approximately 2% live weight), growth, and feed conversion were calculated weekly. After 8 wk, fish were sacrificed, measured, and weighed. Livers were excised and weighed separately, and pooled liver and carcass homogenates were analyzed with standard tissue HPLC techniques to determine vitamin A and E concentrations. Dietary concentrations of vitamins A and E influenced both carcass and hepatic levels of these nutrients, although not to the same degree. A 10-fold increase in vitamin A resulted in a 10-fold increase in carcass vitamin A content (5.8 ± 1.3 vs. 69.0 ± 18.0 IU/g) and hepatic vitamin A concentration (27.7 ± 1.42 vs. 393.3 ± 157.1 IU/g). Similar increases in vitamin E content were noted in hepatic samples (49.5 to 365.6 to 3791.3 µ/g), while carcass concentration increased in a nonlinear fashion (8.8 to 28.1 to 257.5 µg/g). We saw no evidence of nutrient antagonisms at the concentrations fed. Clearly, fat-soluble vitamin concentrations in rainbow trout tissues can be altered by dietary manipulation. Such manipulation may be useful in formulating fish-based diets with known nutrient content, for use in applied feeding programs for piscivorous species.

Speaker Information
(click the speaker's name to view other papers and abstracts submitted by this speaker)

Ellen S. Dierenfeld, PhD, CNS


MAIN : 2000 : Dietary Vitamins A & E
Powered By VIN
SAID=27