Cytochemical Profiles and Quantitative Analysis of Fiber Types in Trunk Muscle of Tigerperch, Terapon jarbua

tigerperch, Terapon jarbua, were classified by cytochemical profiles and image analysis techniques. Serial cross-sections of trunk muscle were examined by evaluating myosin ATPase (mATPase) to categorize the muscle fiber types, by measuring the oxidative enzyme activities of SDH, NADH-TR, and LDH to identify the metabolic patterns, and by determining the glycogen and lipid contents to specify the energy sources. The study revealed 3 muscle patterns (white, red, and pink muscles) distinguished by their enzyme activities. The different fiber types differed in their mATPase activities after preincubation in different pH solutions. Oxidative enzyme activities were quantitatively analyzed and correlated to their gray-level and fiber size. In white muscle only 1 histochemical fiber type (resembling type IIb fiber in mammals, with a large cross-sectional area, CSA) could be identified. Red muscle consisted of abundant type IIc fibers (with a smaller CSA) and a few type I fibers (with a medium CSA) sparsely interposed among IIc fibers. Fibers in a mosaic arrangement of pink muscle, with different histochemical reactions and of various sizes, were classified as type I, IIb, and IIc fibers. Type IIb fiber had larger cross-sectional areas (2969.30 ± 1237.27 ~ 3045.66 ± 1088.87 µm 2 ), type IIc had smaller (318.77 ± 105.02 ~ 353.20 ± 122.18 µm 2 ), and type I had medium areas (708.65 ± 142.62 ~ 1192.09 ± 308.28 µm 2 ).