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The effect of diet on dorsal fin erosion in steelhead trout (Oncorhynchus mykiss)

Aquaculture

By:
,
DOI: 10.1016/S0044-8486(97)00133-6

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Abstract

A 2 X 2 factorial experiment of diet type (krill vs. fish meal) and steroid supplementation (0 vs. 30 ??g 17??-methyltestosterone kg-1) was conducted to determine the effects on dorsal fin erosion in steelhead trout. Triplicate tanks of 250 fry were fed one of the four diets at a rate calculated to produce 115 g fish in 34 weeks. Fish were transferred to larger tanks when mean density index reached 0.40. Dorsal fin index (DFI, measured as mean dorsal fin height X 100/total fish length) was greater (P < 0.001) among fish fed krill-based diets than for fish fed fish-based diets at weeks 12, 22, and 34 of the trial. Added testosterone decreased (p = 0.04) DFI among fish fed the krill diet at week 12 but otherwise had no effect on fin condition. Addition of testosterone to either diet type decreased (P = 0.02) critical thermal maximum, which is a measure of fish resistance to thermal stress. The results suggest that diet composition can influence the rate of dorsal fin erosion in steelhead trout through a metabolic, behavioral, or combined change.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
The effect of diet on dorsal fin erosion in steelhead trout (Oncorhynchus mykiss)
Series title:
Aquaculture
DOI:
10.1016/S0044-8486(97)00133-6
Volume
156
Issue:
3-4
Year Published:
1997
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Aquaculture
First page:
229
Last page:
240
Number of Pages:
12