Rodent Species Diversity and Occurrence of Leishmania in Northeastern Iran

ABSTRACT The aim of the current study was to survey the species diversity and Leishmania infection of rodents in the Gonbad -e- Kavoos City and County, northeastern Iran, during 2018–2019. Totally, 20 rural and four urban areas endemic for leishmaniasis were selected and visited monthly. Rodent species diversity indices were calculated in different spatial and temporal scales. Species richness was also calculated using rarefaction curves to estimate the number of species in unequal sample sizes. A total of 167 rodents belonging to 7 species, 6 genera, and 2 families were collected. Rattus rattus (34.7%) and Rattus norvegicus (18.6%) were identified as dominant species. The largest Margalef and Menhinick species richness (DMg = 1.55; DMn = 1.01) and the highest value of the Shannon index (H′ = 1.71) were observed in rural areas. Seasonal abundance of the rodents varied among species and showed that the highest richness (DMg = 1.27; DMn = 0.65) occurred in spring and the highest value of Shannon index (H′ = 1.72) was noted in summer. Rarefaction curves confirmed that the highest species richness occurred in summer and spring in the rural area. Seasonal fluctuations of R. rattus and R. norvegicus have a significant impact on the changes in rodent species diversity. Investigations of Leishmania infection showed that amastigote forms of Leishmania were observed in 15.4% of smears taken from Rhombomys opimus and Meriones libycus and examined under the light microscope. The highest rate of Leishmania infection was observed during the summer.