Maintenance in vitro of adult Fasciola hepatica in a continuous-flow system

A continuous-flow apparatus is described for the maintenance of groups of adult Fasciola hepatica. The ammonia produced by the flukes was used as a measure of their metabolic activity and it was shown that this is best maintained in culture fluids containing a large proportion of bovine serum. More ammonia per fluke was consistently produced when the flow rate of the medium was increased but including small pieces of clotted sheep blood or increasing the number of flukes per culture had no significant effects.