Atrophy and Muscular Fibrosis of Unknown Etiology during the Raising of Xiphophorus maculattus on an Ornamental Fish Farm

During the last two decades, the implementation of histochemical, immunohistochemical, electron microscopy, and recently developed molecular techniques has greatly contributed to our knowledge of skeletal muscle, both normal and sick. This article reports the presence of muscular atrophy and fibrosis in Xiphophorus maculatus from an ornamental fish farm. We do not know the origin of this muscular pathology and the purpose of this work is to summarize some of the findings with optical microscopy and electron microscopy shared by all. Although we cannot establish the etiology of this atrophy, we will try to correlate the ultrastructural alterations with the muscular histopathology. Muscular atrophy is a pathology characterized by loss of normal muscle mass. It is caused by a decrease in the total number of muscle cells or by a substantial reduction in the substance of individual muscle cells. It is likely that the cases reported here represent a pathology involving causes concurrent with nutritional problems and disorders of muscle innervation. Therefore, future studies should investigate further about the potential of neurodegenerative disorders. Several experimental models can use muscular atrophy and are suitable for investigations of the underlying mechanisms of this pathology.