[The taxonomic position of nematodes in the genus Trichinella Railliet, 1895]

Abstract

In the author's opinion, the recent taxonomic revision of the genus Trichinella Railliet, 1895 (Pozio et al., 1992 and others) seems to be hasty and insufficiently substantiated. The proposed criteria for identification of new species, such as production of new-born larvae (PNBL) by Trichinella females in vitro, periods of development of nurse cells (DNC), index of reproductive capacity (IRC), resistance to freezing (RF), firstly, have a sufficient dispersion and are frequently very close (PNBL) to T. britovi, T. nativa, T. nelsoni, and T. pseudospiralis, DNC for these species. Secondly, these criteria are not always precise (one cannot agree with the fact that T. spiralis are not resistant to freezing). And, finally, it is impossible to be guided seriously by such criteria as the low or high significance of IRC or RF. According to the fifth criterion--the number of unique allozymic markers--two species are obviously distinguished: T. spiralis (6 markers) and T. pseudospiralis (12 markers). If the absence of capsule formation in case of T. psuedospiralis and the participation of birds in the life cycle of this parasite will be added to the above-mentioned, two species are again clearly distinguished: T. spiralis and T. pseudospiralis. Presently, it is necessary to classify the remaining species as varieties of subspecies of T. spiralis and to designate T. spiralis nativa, T. spiralis nelsoni, T. spiralis britovi, as recommended by the "Guidelines on Surveillance, Prevention, and Control of Trichinellosis" published by the WHO in 1988.