Echinostoma caprom' infection in non-pregnant female BALB/c and Swiss T.O. mice: effect on feed intake, liveweight, and serum pregnancy-associated murine protein-l and corticosterone

Abstract

The effect of experimental infection with the intestinal ti'einatode. Echinosloma caprani, on feed intake, liyeweight and serum pregnaney-associated murine protein-l (PAMP-1) and corticosteronc was investigated in non-pregnant female BALB/c
and Swiss T.O. mice. Twenty-five metacereariae were given by oral gavage on day 0 of which 19.6 % were recovered at post monem on day 46 in the BALB/c mice and 22.0 % in the Swiss T.O. mice. Oral praziquantel treatment (50 mg/kg) on day 39 reduced the recovery of tlnkes from previously-infected mice by 85.4% and 100% in BALB/e and Swiss T 0 mice respectively. The food consumption in the infected Swiss T.0. mice was significantly increased compared to the infected-treated and the controls. In the BALB/c mice the food intake in the infected and infectedtreated animals was significantly increased compared with the controls, The liveweight gain during the experiment in the BALB/e control mice was significantly higher than in the infectedtreated groups. In the Swiss T.0. mice the infected animals gained more weight than the controls and the infected- treated animals. E. caproni was associated with a significant reduction in PAMP-l concentrations in both strains of mice, even in animals from which the majority of flukes had been removed by praziquantel-treatment. There was no significant correlation between the magnitude of the parasite burden and serum PAMP~1 values. Corticosterone values were unaffected by either mouse strain, E. capromi infection or anthelmintie treatment. These results suggest that the previously reported adverse effect of E. capromi on early pregnancy in mice may be caused by parasiteiinduced effects occurring prior to fertilisation.