Dog hookworm (Ancylostoma caninum), SEM

Coloured scanning electron micrograph (SEM) of Dog hookworm (nematode, Ancylostoma caninum). The adult parasites are small cylindrical worms 0.5, 1.5mm long. The genus Ancylostoma have pairs of teeth on the ventral margin of the buccal capsule. The posterior end of the male worm is equipped with a characteristic copulatory bursa, used to catch and hold the female nematode during mating. The eggs are passed in the faeces and once exposed to air they mature rapidly under optimal temperature and moisture. When mature they hatch to liberate a rhabditiform larvae. Larvae pass to the outside through human faeces and subsequently re-enter their host by burrowing through the skin. After migrating through the lungs they settle in the gut and become sexually mature. The adult hookworms attach themselves to the intestinal wall using the buccal capsule teeth. Magnification x8 (inset x50) when shortest axis printed at 25 millimetres.