E. Favaloro et A. Mazzola, Meristic character analysis and skeletal anomalies during growth in rearedsharpsnout seabream, AQUACUL INT, 8(5), 2000, pp. 417-430
Sharpsnout seabream (Diplodus puntazzo) is a species currently reared in Me
diterranean fish farms. In order to detect the main types of body deformati
on in sharpsnout seabream, 120 specimens (60 juveniles and 60 adults) taken
from a Mediterranean hatchery were examined. In juveniles and adults non-s
ignificant differences were found in the number of vertebrae, dorsal spines
and pectoral fin rays. Moreover, the number of anomalies varied with age.
The juveniles presented 28 types of anomaly, the adults 25. The most import
ant anomalies for juveniles (in terms of frequency of occurrence) were anom
alous neural arch or spine (47%), anomalous hemal arch or spine (43%), fusi
on of hypurals (67%) and presence of calculi in the terminal tract of urina
ry ducts (43%), while for adults were anomalous neural arch or spine (43%),
fusion of hypurals (90%) and fusion of epurals (37%). While anomalous hema
l arch or spine and presence of calculi in the terminal tract of urinary du
cts decreased with age, fusion of hypurals and fusion of epurals increased.
Lordosis and kyphosis were found in a slight form only in juveniles and wi
th a low frequency of occurrence. These decreased or disappeared in adults.
No mortality was detected either in juveniles or in adults. In any case, t
hese anomalies did not influence the growth performance of juveniles and no
lethal anomalies were detected.