Fig. 4. Optical microscope micrograph of histopathological assessment of muscular tissues dissected from articulations affected by a parasitic infection in Campephilus magellanicus: (A) Sample from the right knee exhibiting loss of the skeletal muscle architecture and nematode eggs (dark dots at lower half), contiguous to muscle fibers with normal tissue architecture (upper half), Bar = 200 μm. (B) Sample from the left tibiotarsus mass showing myofibers of variable shape and size, diffuse mononuclear infiltration, and several eggs, Bar = 100 μm. (C) Two thin-shelled eggs with fully differentiated L1 at the centre of the image, surrounded by mononuclear cells, Bar = 20 μm.