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damage (e.g., ruptured chorion) and measured (maximum diameter) under a stereo-zoom dissecting microscope. After stripping, fish were immediately euthanized with an overdose of tricaine methanesulfonate (MS-222), labeled as to treatment, and placed in an ultra-cold freezer at -840C for later internal examinations. Fertilized eggs from each treatment replicate or the control were placed in separate plastic bags, bags were inflated with pressurized O2 and sealed, and eggs were transported to Colorado State University, Fort Collins. In the laboratory, a sample of eggs from each treatment replicate or the control was divided into 5 (shocked replicates) or 10 lots (contro!), each with 500 eggs. Each lot of eggs was placed in a separate incubation basket that was randomly positioned in a flow-through trough receiving well water at 180C. Eggs were examined at least twice daily during incubation, and obviously dead eggs in each lot were recorded and removed to reduce spread of fungus. Time of hatching (hours post-fertilization) and hatching success were recorded for each lot of eggs. Weighted analysis of variance was used to compare mean egg hatching success among treatments and the control because of unequal number of egg lots. Fisher's pair-wise comparison test was used to identify significant differences (P ~ 0.05) between individual means. For internal examination of adults, fish were partially thawed, X-rayed dorsally and laterally (left side) with a portable MinXray@ model X750-G on 3M@ medical imaging film (35 X 43 cm), and necropsied. X-ray plates were inspected for evidence of damage to vertebrae. Necropsy consisted of filleting fish along both sides of the spine and then examining the spinal column and surrounding musculature for evidence of hemorrhages. Fish were also opened along the mid-ventral line, from vent to head, and examined for evidence of damage to internal organs. Type and severity of injuries associated with the spinal column were classified according to criteria proposed by J. B. Reynolds (Alaska Cooperative Fish and Wildlife Research Unit) as presented in Hollender and Carline (1994). Vertebral injuries were classified as: compression of vertebrae (class 1), misalignment and compression of vertebrae (class 2), or fracture of ~ 1 vertebrae or complete separation of ~ 2 vertebrae (class 3). Hemorrhages were classified as: wounds separate from spine (class 1), wounds on spine::;; width of 2 vertebrae (class 2), or wounds on spine> width of 2 vertebrae (class 3). Results Tetany was induced in all shocked fish during treatment, but those exposed to CPS continued to quiver after they appeared to be tetanized, whereas fish subjected to the 50-Hz current did not. All males and females exposed to either current 7