Tissue damage in fish Johnius dussumieri infected with Ichthyophthirius multifiliis from Karachi coast Pakistan

Tissue damage observations are made on the skin infection of the fish Johnius dussumieri infected with Ichthyophthirius multifiliis. For this purpose histological sections were prepared by usual technique, stained with haematoxylin and eosin, dehydrated in graded series of alcohols, cleared in clove oil and xylene and mounted permanently in Canada balsam.Photographs were prepared with Nikon (Optiphot-2) photomicroscope using a Fuji colour film. This infection severely damaged the skin tissue, common findings were erosion of outer surface, dislocation of muscle fiber and shrinkage and atrophy which produced large spaces in between the muscles fibers. Hyaline degeneration of muscles fiber was also prominent in some sections. Muscle fibers were severely damaged and fragmented.