Oral, parenteral and paratenic infections of mice with Toxocara pteropodis

Oral, parenteral and paratenic infections of mice with Toxocara pteropodis. International Journal for Parasitology 16: 471-474. Groups of adult male CBA mice were inoculated with 7500 eggs of Toxocara pteropodis intragastrically, 2000 eggs subcutaneously or 2000 eggs intraperitoneally. Regardless of the infection route, larvae accumulated in the livers of these mice in comparable numbers. Following peroral infection, most larvae rapidly appeared in the liver with very small numbers passing through mesenteric lymph-nodes to the lungs. Intraperitoneal inoculation of eggs was followed also by a rapid accumulation of larvae in the liver, with larvae being recoverd also from lungs, intestines and other organs. Larvae from subcutaneous sites passed through the lungs en route to the liver, where they accumulated more slowly. Larvae within acutely-infected mouse lung and chronically infected flying fox liver which were fed to non-infected mice were capable of invading the livers of the latter, indicating a relict paratenic tendency. This marked hepatotropism of T. pteropodis indicates that larval accumulation in host livers is a goaldirected phenomenon independent of host capillary dimensions