Spontaneous skeletal deformities in the Zebra Danio (Brachydanio rerio) bred for fish toxicity tests



Zebra Danio (Brachydanio rerio, Hamilton-Buchanan) tropical fish are easily maintained and bred under laboratory conditions; procedures for maintenance and breeding are described. Intensive inbreeding of this fish gave rise to a high incidence of spontaneous skeletal deformities which appear to reflect a genetic defect rather than an environmental stimulus. This finding casts doubt on the suitability of the Zebra Danio for fish toxicity testing.