| Abstract: | Metacercariae of Fasciola hepatica were labeled with 75Se by exposure of infected Lymnaea columella to 75Se-M, 20 muCi/snail, in 5 ml of water. Seventy-two mice were inoculated with 50 75Se-labeled metacercariae. At intervals after infection, the distribution of metacercariae in gut, body cavities and liver was studied by compressed organ autoradiography, and a variant of this technique adapted to gut content and body cavity washes. Ag degree focus counts from autoradiograms expressed as percentage of actual exposure level were subjected to probit analysis. Estimates of the average departure time of radio-labeled maritas from gastrointestinal tracts and average arrival time into the abdominal cavities were 12.2 and 12.5 h, respectively. The peak accumulation of maritas in abdominal cavities occurred at 24 h post-inoculation. A 7.7-h discrepancy between estimated average departure time from abdominal cavities (92 h) and average arrival time at livers (99.7 h) was attributed to experimental error. |
