Abstract
Cadmium toxicity to rainbow trout was evaluated at two cadmium concentrations (0.01, 0.10 mg1−1) and in water without added cadmium using eggs reared through the larval (alevin) phase to swim‐up fry. Exposure to 0.1 mg Cd 1−1 promoted premature hatching, retarded growth, increased rates of mortality and the occurrence of developmental abnormalities such as spinal curvature and blood clots. Three methods of holding the eggs and alevins during the toxicity test were compared. Hatching time and success, alevin mortality, growth and development were not influenced by the method of containment but of the three methods, a subdivided perforated box system proved particularly useful for monitoring the responses of specific animals throughout the toxicity test.
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