In search of pathogenic Leptospira species in Myotis and other vesper bats, Russia.

Various bat species worldwide have been identified as Leptospira carriers, especially in tropical regions. In this study, we investigated the infection of Vespertilionidae bats by pathogenic Leptospira in north-west Russia. Out of 264 bats from 13 species, the urine of 24 specimens tested positive according to a polymerase chain reaction test.

Parasite abundance distribution as a model of host-parasite relationships between monogeneans Gyrodactylus spp. and cage-reared rainbow trout Oncorhynchus mykiss.

Aggregation is a fundamental feature of parasite distribution in the host population, but the biological implications of the aggregation indices used to describe the relationships between the populations of parasites and hosts are not evident. It is speculated that the form of distribution in each case is predicated on the host's varying resistance to the infection, which is hard to control, making it difficult to adequately interpret the index values. This paper examines several cases from trout farms in Russian Karelia to explore the monogenean Gyrodactylus spp.