Egg production by Trichobilharzia ocellata (Trematoda: Schistosomatidae) after initial and challenge infection in ducks

Abstract

Evaluation of reproductive success by Trichobilharzia ocellata was based upon numbers of miracidia hatching in sidearm flasks. Hatchable eggs appeared in feces 13–14 days after the duck's foot was exposed to cercariae, rose to peak numbers by about day 19, then declined to zero, usually by day 45. Patent infections also resulted from implantations of 10–100 unsexed adults and in some but not all birds exposed to 10–25 cercariae on 51 consecutive days. Most birds challenged by massed cercariae failed to support egg-laying second populations regardless of whether the initial infection followed cercarial invasion or implantation of adults.