title: Effects of a 100 metacercarial cyst inoculum on the host-parasite relationship of Echinostoma caproni and ICR mice.
abstract: The host-parasite relationship of a 100 metacercarial cyst inoculum of Echinostoma caproni in the ICR mouse was examined. Three groups of mice, A, B and C, each with six mice per group were used and all mice were necropsied at 14 days postinfection (p.i.), at which time the worms were ovigerous. Group A consisted of uninfected controls, whereas group B received 25 cysts per mouse (low dose) and group C received 100 cysts per mouse (high dose). There was no significant difference in food consumption between any of the groups from 0 to 14 days p.i. Control mice increased their body weight by 12%, group B by 5%, and group C showed a less than 1% increase in body weight between 0 and 14 days p.i. Echinostome parasitism caused a significant increase in the diameter of the mouse gut, with the gut of group C being more significantly dilated than that of either group A or B. The average worm recovery from group B was 20 worms per host, compared to 72 worms per host from group C. The mean wet and dry weights per worm from group B were 2.4 and 0.4 mg, respectively as compared to 0.6 and 0.2 mg respectively for group C. The mean number of uterine eggs per worm from group B was 180 compared to 125 for worms from group C. Worms from group C were more widely distributed in the small intestine than those from group B. Crowding effects associated with the high dose infection were clearly demonstrated in E. caproni from ICR mice.
authors.affiliation: Department of Biology, Lafayette College, Easton, Pennsylvania 18042, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Balfour
authors.forename: M
authors.initials: M
authors.lastname: Rossi
authors.forename: B
authors.initials: B
authors.lastname: Fried
mesh_terms: D000818:Animals; D001699:Biometry; D004435:Eating; D004449:Echinostoma / Q000302:isolation & purification / Q000502:physiology*; D004451:Echinostomiasis / Q000469:parasitology* / Q000473:pathology; D005260:Female; D006790:Host-Parasite Interactions; D007421:Intestine, Small / Q000469:parasitology / Q000473:pathology; D051379:Mice; D015430:Weight Gain