Ultrastructure Morphology of the Pseudophyllidean Cestode Bothriocephalus Achilognathi, from Schizothorax Species of Kashmir

The ulrastructural morphology of the cestode Bothriocephalus acheilognathi (Yamaguti, 1934) has been studied by SEM (scanning electron microscopy) and TEM (transmission electron microscopy). This parasite was isolated from the Schizothorax species from fresh water bodies of Kashmir. Adult Bothriocephalus acheilognathi ranged from 3.5 to 13.5 cm long and 0.36 to 1.44 mm wide. This cestode presents three types of microtriches., the first type corresponds to a large and thin structure, the second type is short and wide, both types are found on the scolex and the strobila. The third type is observed exclusively at the bottom of the bothria and is larger and thinner than the first type. Sensilla are located at the tegument surface. These sensitive organs are distributed on the scolex and stroblia., their cilia never protrude higher than the surrounding microtriches. The bulb of the sensilla is connected to the dystal cytoplasm by septate desmosomes and a single electodense collar. Other structures of the tegument are the dome shaped tumuli, present exclusively on the scolex and containing dense staining inclusions. They are discharging structures originated at the unicellular glands of the perinuclear cytoplasm. Muscle bundles are present in the perinuclear region below the basal membrane. These smooth muscle fibers present two orientations. Between the muscular zone and the perinuclear cytoplasm there is an intermediate zone clearly observable at the scolex and less defined but present at the proglottids. This zone is packed with cytoplasmic projections, which contain rabdiform bodies, mitochondria and abundant glycogen. The Golgi bodies indicate a cell actively secreting proteins. In the region of the perinuclear cytoplasm, in addition to the unicellular glands and the mucous secretory cells, the main organs are vitellogenic glands, protonephridial system, gonads and accessory structures. Storage structures rich in reserve material are also observed.