Fasciola hepatica

Fasciola hepatica. Adult worm (carmine stain, scanning power). These large, fleshy flukes of humans and herbivorous animals live in the bile ducts, measure up to 30 mm long, and have a spinous tegument. They have a characteristic cone- shaped anterior end, with extensive branching of the intestine and reproductive organs. Two highly-branched testes lie one behind the other toward the posterior part of the body. The ovary is also branched and lies anterior to the testes. A dark-staining uterus is in the anterior third of the worm with the genital pore located near the ventral sucker. The vitellaria are the brown-staining structures occupying the lateral fields from the ventral sucker to the posterior extremity.