Dr. Murai Éva szerk.: Parasitologia Hungarica 20. (Budapest, 1987)
Pathogenecity of Trypanosoma equiperdum to different rodents. II. Susceptibility of the common vole (Microtus arvalis)* Dr. Györgyi HORVÁTH' — Dr. Ferenc VETÉSI 2 — Dr.Ferenc KEMENES 3 Department of General Zoology and Parasitology' and Department of Pathological Anatomy 2 , University of Veterinary Science, and PHYLAXIA' Veterinary Biologicals Co., Budapest, Hungary "Pathogenecity of Trypanosoma equiperdum to different rodents. II. Susceptibility of the common vole (Microtus arvalis)". - Horváth, Gy. - Vetési, F. - Kemenes, F. - Parasit, hung., 20: 33-39. 1987. ABSTRACT. A total of 184 voles and 120 albino mice were infected intraperitoneal^ (and sometimes subcutaneously ) with blood taken from trypanosomeinfected albino mice in agony. Five to 25% of voles infected with a rather large dose (2-4 x 10^ trypanosomes) died, whereas those treated with smaller doses survived. In voles killed on PI days 4-5 there was a 6- to 10-fold, whereas in voles surviving a stronger infection a 10- to 18-fold splenomegaly, as compared to uninfected control litter mates killed at the same time. Albino mice were killed by smaller doses of trypanosomes in a few days' time. At the time of death they had an only 2- to 4-fold splenomegaly. In the blood of the surviving voles the trypanosomes occasionally persisted for a month, and in their serum the trypanosomal antibodies were demonstrable for 3 months. Histopathological examination revealed cell proliferation in the spleen and pronounced activation of the macrophages. Thus, the vole has proved to be a suitable experimental model tor detailed studies on the pathomechanism of T. equiperdum infection, and primarily on the successful defence mechanism of the organism. KEY WORDS: Trypanosoma equiperdum, vole, resistant rodent, enlargement of spleen, macrophag activation. In a previous paper (KEMENES and HORVÁTH, 1986) we have reported that the vole, a rodent native to Europe, is resistant to Trypanosoma equiperdum (Doflein, 1901) infection which is always lethal to mice and rats. PACHANIAN (1963) conducted experiments on 21 rodent species indigenous to America, in order to assess and compare their susceptibility to T. equiperdum. Thirteen out of the 21 species proved to be susceptible and eight were resistant. Peronryscus mamcuJat^s^ambeJLli was the most resistant: the deer mouse carried the flagellates for as long as 81- 1596 days. The vole R^cj^tuj_arvalis_(Pallas, 1779) was not included in this comparison. The aim of the present investigations was to determine whether the vole, which is one of the commonest wild rodents in Europe, is susceptible to T. equiperdum, and if not, what is the mechanism of its resistance. Based on a paper read at the scientific conference of the Hungarian Society of Parasitologists held in Szombathely, on 29 May, 1986.
