Fig. 3.

Anaerobic white muscle fiber cross sections from black sea bass with body masses of 0.45 g (A), 4 g (B), 30 g (C), 310 g (D), 1885 g (E) and 3200 g (F) with DAPI-stained nuclei and Acridine-Orange-stained fiber cytoplasm. Note that fibers from smaller fish grew hypertrophically into larger fibers, and hyperplasia (appearance of new, smaller fibers) and/or fiber splitting was observed in the largest size classes (arrow in F). Changes in nuclear distribution were also apparent. Fibers from juvenile fish (A–D) contained low numbers of almost exclusively SS nuclei, whereas as the fish and muscle fibers grew, numbers of IM nuclei increased (arrowheads in E,F). Scale bar, 100 μm.