Migration Routes of Toxocara Canis and Toxocara Cati in Tissues of Experimentally Infected Rattus Norvegicus

Toxocariasis is currently considered an important zoonosis in many countries and is usually attributed to larvae of Toxocara canis Werner, 1782 but less frequently, T. cat. This study attempts to compare the migration routes followed by T. canis and Toxocara cati (Schrank, 1788) in Rattus norvegicus Berkenhout, 1769 and to determine the percentage of larvae recovered in each organ of experimentally infected rats. Twenty-one 8-week-old, male specimens of R. norvegicus (Wistar) were inoculated orally with 500 embryonated eggs of T. canis, while another 21 rats of the same species were inoculated orally with 300 embryonated eggs of T. cati. On postinfection days 3, 5, 8, 10, 15, 30 and 60, three rats from each group were sacrificed and larval recovery was performed from various organs and the carcass following digestion with 0.5% HCl method. Comparisons of the percentage of recovered larvae revealed that T. cati larvae migrated in greater quantities, as early as day 3 postinfection, to the lungs (23.77%, compared to 0.34% for T. canis), while migration of T. cati larvae to the carcass was observed from day 3 up to day 60 postinoculation. This experiment verified that the larvae of these two species follow distinct migration routes and have different recovery rates.