Skeletal characterization of wild and reared zebrafish: anomalies and meristic characters

Among two groups of wild and reared zebrafishes (zf) Danio rerio, all meris tic characters considered were variable except the numbers of rays and pter ygophores of the dorsal fin and the principal caudal fin rays, which tended to be canalized. Wild and reared individuals differed in the number of int ervertebrae and anal pterygophores, and the dorsal and anal fin insertion. There were some skeletal anomalies of vertebrae and fins, particularly the caudal fin. Cephalic and Weber-apparatus anomalies were rare. Types and fre quencies of anomalies were quite similar in the two zf groups, but differen ces emerged for several less frequent anomalies. Such differences and the p henotypic variability of D. rerio make this species a perfect teleost model for investigating the influence of experimental or unfavourable environmen tal conditions on skeletal development of both domesticated and wild fish. (C) 2000 The Fisheries Society of the British Isles.