Body shape variation in meiotic gynogenetic and triploid sea bass, Dicentrarchus labrax

Abstract

A method of geometric morphometrics was used to characterize body shape variation in meiotic gynogenetic and triploid sea bass in comparison with diploid controls. A total of 13 coordinate landmark data were recorded on the profile of 34-month-old control (n = 81), gynogenetic (n = 117) and triploid (n = 131) siblings generated from two females (A and B). Three main axes of morphometric variation were consistent, and these accounted for 60.8 and 57.6% of the total variability in females A and B, respectively. There were significant shape deviations of triploid and gynogenetic fish relative to the controls, and differences were particularly evident in the progeny of one female. Overall,triploids displayed a more slender shape than diploids, whereas gynogenetic fish were deeper bodied and had flexed caudal peduncles and cranial features. The results are discussed especially in relation to the characterization of triploid fish for commercial purposes.