Dr. Murai Éva szerk.: Parasitologia Hungarica 12. (Budapest, 1979)

The Course of Primary and Secondary Nippostrongylus brasiliensis Infection in the Multimammate Rat (Mastomys natalensis) and Albino Rat Dr. Péter REDL — Dr. Tibor KASSAI Helminthological Research Laboratory Department of Parasitology, Veterinary University, Budapest "The course of primary and secondary Nippostrongylus brasiliensis infection in the multimammate rat (Mastomys natalensis) and albino rat" - Redl, P. - Kassai, T. Parasit. Hung. 12_. 71-78. 1979. ABSTRACT. In experiments which included a total of 117 M. natalensis and 40 albino rats it was evidenced that in the former host the course of larval Nippostrongylus infection was characterized by prolonged prépaient period, low take, low level and short duration of the egg output and rapid worm rejection. These features appear to indicate a lower degree of adaptation of N. brasiliensis to the mastomys than to the rat. Infected multimammate rats develop strong immunity to reinfection. By virtue of its prolificity, thoughness and small body dimensions, the multimammate rat, Mastomys natalensis, has recently been increasingly used as experimental animal alternatively to rats and mice in laboratory investigations (for references see REDL and GYŐRFFY, 1978). Parasite-infected mastomys hosts have among others been used for laboratory screening tests in anthelminthic assays. The reliable evaluation of such tests presupposes the precise knowledge of the life cycles of different parasites in Mastomys natalensis. LÄMMLER et al. (1968) and PANDE et al. (1977) reported that Nippostrongylus brasiliensis was able to establish itself in the multimammate rat. However, certain details of the course of infection and the immunogenic capacity of the infection remained to be clarified. Investigations into these aspects are reported in this paper. EXPERIMENTAL .Materials ami Methods Female CFY rats 5-10 weeks old, and above 5 weeks old Mastomys natalensis (yellow-haired, red-eyed) of both sexes, from the colony of the National Institute of Haematology and Blood Transfusion (Budapest) were used. Infective larvae of N. brasiliensis were obtained and infection experiments performed as previously described (TAKÁTS, 1972). Post mortem worm counts and localizations were determined in situ under stereomicroscope in the small intestine opened longitudinally and divided into 5 cm long portions. Egg counts (eggs per gram faeces, EPG) were made daily or every other or third day by the McMaster method.