Histochemical and morphometric aspects of the lateral musculature of different species of teleost marine fish of the percomorphi order

Abstract

Cross-sections of the lateral musculature of 19 species of teleost fish of the Percomorphi order were studied histochemically and morphometrically. The red, pink and white muscles were observed in all the species except in Seriola dumerilii and Scomber japonicus, in which no pink muscle was found. The red fibres were the smallest due to their minimal diameters. Histochemically and according to their location at least five types were found in the same species: typical red, in rosette, of the border, infiltrated pink and in mosaic. The pink fibres were larger than the red but smaller than the white. The form and disposition of the pink muscle varied according to the species. This muscle is made up by fibres of medium size, moderate m-ATPase and intermediate oxidative activities. Their histochemical properties change near red and white muscles, where they acquire the histochemical characteristics of the typical red fibres or the low m-ATPase activity of white fibres, respectively. The white muscle is the widest muscular layer. All of the species, except Thalassoma paro are made up by three fibre types (small with high m-ATPase activity, medium with moderate m-ATPase activity, and large with low m-ATPase activity).They are mixed and show a histochemical and morphometric mosaic form. The extent of this mosaic depends on the species. In most of the analysed species it was observed in areas close to the pink muscle, but in three of them (Liza aurata, Seriola dumerilii and Coris julis) it occupied all of the myotome.