[Course of Trichostrongylus retortaeformis (Zeder, 1800) Looss, 1905, infestation in the domestic rabbit (Oryctolagus cuniculus)].

Fifty Havanna, Small Chinchilla and crossbred rabbits were each infected at 3 to 4 months of age with a single dose of 5-20 thousand third-stage larvae of the trichostrongyle. After infection with 10 thousand larvae, third-stage larvae were present on the 1st and 2nd days, fourth-stage on the 4th-6th days, fifth-stage on the 7th and 8th days and sexually mature trichostrongyles on the 8th-10th days. Only a small proportion of third-stage and fourth-stage larvae failed to develop into sexually mature neamtodes. Prepatent period of infection was 9-10 days; patency lasted from a few weeks to 2-3 months. Single infection with 5000-7000 invasive larvae produced no clinical signs. A dose of 10 thousand larvae produced diarrhoea even during the prepatent period, and this was accompanied by expulsion of a considerable part of the parasite population. Infection with 20 thousand larvae produced a loss of weight in the experimental rabbits.