Morphological and morphometric analysis of skeletal muscle between male and female young adult Colossoma macropomum (Characiformes: Serrasalmidae)

Abstract

ABSTRACT This study aimed to evaluate muscle organization in tambaqui in order to describe the muscle growth process. We analyzed the morphometric pattern of fibers from white muscle of young-adults (300 days) by smaller diameter. The organization of white muscle exhibited a typical morphological pattern found in other fish species. Heavier animals showed higher frequency of larger diameter fibers (>50 μm ) and smaller animals had higher frequency of smaller diameter fibers (50 μm ) than males. However, there was no difference between body weight and sex (P =0.8). Our results suggest that muscle growth is by hypertrophy and hyperplasia due to a mosaic appearance from different diameters fibers, which is characteristic of large size fish species.

Keywords

• Hypertrophy
• Hyperplasia
• Muscle growth
• Sexing
• Tambaqui