7948

• UCREFRP Catalog Number: 7948
• Author: Martinez, A. M.
• Title: Observed Fin Ray Deformities Resulting from Handling Stress in the Intensive Culture of Razorback Suckers.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: NO

Anita M. Martinez 4
developed severe fin deformities by the time they were juveniles. This malady has not
been formerly reported in literature concerning the intensive or extensive culture of this
species. The objectives of this study were to determine if nutrition, environment, or genetic
predisposition caused fin deformities in the 1993 year class of razorback suckers and at
what developmental stage onset of fin deformities occurred.
Methods
Four razorback suckers, tvuo males and two females were spawned in 1994, at the
CDOW s Horse Thief Canyon State Wildlife Area (SWA), near Fruita, Colorado. Both
females and one male were wild fish collected in 1993 from the Colorado River near Grand
Junction, Colorado. The other male was collected from a gravel pit pond (Etter Pond}
located near De Beque, Colorado. Each of the four crosses of known parental identity
were kept separate, assigned an identifying letter (Lot A,B,C,D), and transferred for
hatching and rearing to the FRH, Bellvue, Colorado. Fertilized eggs were placed on 1.5
mm nylon mesh hatching trays submersed in 3.5 L plastic rearing trays. The rearing trays
were fitted with two 155 mm x 60 mm windows, covered with 0.5 mm nylon mesh. Water
flowed through these windows and each tray was aerated with a 25 mm long by 15 mm
diameter air stone.
The rearing trays were arranged in 109 L stainless steel troughs supplied with
heated, degassed well water (average flow, 6.04 Umin; -average temperature, 21.1 °C;
dissolved oxygen, 7.4 mg/L; pH, 7.8; total hardness, 265 mg/L; total alkalinity, 215 mg/L;