Fasciola

The life history of a nematode (the liver fluke), showing in detail its structure and its habits. The habits of the snail are then examined and shown to be a source of danger of infection. A detailed study of the life-cycle of the liver-fluke, showing the egg and the first larvae, the intermediate host - a snail, the second larvae, and, finally, the encysted third larvae, which are a source of infection to sheep, cattle, horses, dogs, and humans. The film shows that the most effective methods od dealing with fluke is to eliminate the conditions which are favourable for the breeding of the intermediate host, the snails. A gap is thereby created in the life-cycle of the fluke, as it cannot reproduce without the snails to act as intermediate host to the first larvae.