Morphology and muscle fiber diameter of artificial hybrids between red seabream and crimson sea bream - Development of new sea bream seedlings by hybridization-I

Red sea bream Pagrus major, red sea bream female x crimson sea bream Evynni s japonica male (F-1), and red sea breana female x F-1 male, (RF1), with bo dy length (BL) of 35 similar to 41 cm and 2 similar to5-year-old, and crims on sea bream, with BL of 25 similar to 33 cm and 8-year-old, in attempt to develop new sea bream seedlings, were compared with their muscle Faber diam eters. These lashes were fed on artificial diets commercially available and reared in net pens settled in the Uragami Bay, near the Peninsula of Shion omisaki. The RSB, RF1, and F-1 had significantly lower relative head length , caudal peduncle length, body height, and eye diameter to the BL than thos e of CSB. Relative snout length and head hight to body length, lateral line scales, and gill rakers showed an increasing trend in the order of RSB, RF 1, F-1, and CSB. Fiber diameter frequency of white muscle under the tip of dorsal fin also slided to an increasing direction in the order of RSB, RF1, F-1, and CSB. These results indicate that the backcross RF1 morphometrical ly approach to RSB more than F-1 and CSB.