Intestinal helminths infection of rats (Ratus norvegicus) in the Belgrade area (Serbia): the effect of sex, age and habitat

Abstract

Gastrointestinal helminths of Norway rat (Rattus norvegicus) from the Belgrade area were studied as a part of a wider ecological research of rats in Serbia (data on the distribution, population ecology, economic and epizoothiological-epidemiological importance, and density control). Rats were captured from May 2005 to July 2009 at both urban and suburban-rural sites. Of a total of 302 trapped rats 48% were males and 52% females, with 36.5% and 38.8% of juvenile-subadult individuals, per sex respectively. Intestinal helminth infection was noted in 68.5% of rats, with a higher prevalence in male hosts and in adult individuals. Higher numbers of infected juveniles-subadults were noted in suburban-rural habitats, while an opposite tendency was noted in adult rats. Seven helminth species were recovered, of which five were nematode (Heterakis spumosa, Nippostrongylus brasiliensis, Capillaria sp., Trichuris muris and Syphacia muris) and two cestode species (Hymenolepis diminuta and Rodentolepis fraterna). The most prevalent parasites were Heterakis spumosa (36.7%) and Hymenolepis diminuta (30.5%). Sex and habitat-related differences were noted in the prevalence of infection with Capillaria sp. and Trichuris muris, while there were no age-related differences in the prevalence of infection with any individual helminth species. Significantly higher prevalence of infection was noted in summer as compared to spring or winter, with a tendency to be higher in autumn as compared to spring. The only significant difference in the prevalence of infection between habitat-related was noted during spring. H. spumosa was most prevalent in summer, while H. diminuta and N. brasiliensis in autumn. The mean intensity of infection with H. spumosa, R. fraterna, S. muris and T. muris was higher in autumn than in the other seasons, while N. brasiliensis and Capillaria sp. occured in winter. No more than four helminth species were found in one host.

Helminth Diversity in Synanthropic Rodents from an Urban Ecosystem

“…The success of murine rodents in anthropogenic habitats could be the reason for many parasitological studies done worldwide. In general, studies have focused primarily on list of all parasites species and analyzed biotic and abiotic factors influencing composition and parasite burden (see Battersby et al 2002;Milazzo et al 2010;Easterbrook et al 2007;Kataranovski et al 2008Kataranovski et al , 2011Hancke et al 2011). In recent decades, the detection of diseases associated with rodents as reservoirs has increased (see Meerburg et al 2009), which gives them a significant role in disease transmission to humans.…”

Hymenolepiosis in a group of albino rats (Rattus albus): a study

“…In an another study Waugh et al (2006) recorded low level of infection of H. diminuta (3.8 %) out of nine species of gastrointestinal helminths recovered from rats in Jamica whereas Kataranovski et al (2011) reported H. diminuta infection (30.5 %) as most prevalent among seven helminth species identified in rats (Ratus norvegicus) in the Belgrade.…”

Helmintofauna Gastrointestinal de Importancia Zoonótica y sus Aspectos Patológicos en Roedores (Rattus spp) en Tres Medioambientes

“…Se registró el sexo, la procedencia y los parámetros morfométricos (longitud total, largo de cola, patas y orejas y el peso) para establecer la especie. Como edad se consideraron dos categorías: juvenil-subadulto y adulto, donde los roedores Rattus rattus se clasificaron como adultos con un peso mayor de 130 g (Milazzo et al, 2010) y los Rattus norvegicus con un peso mayor de 200 g (Kataranovski et al, 1994).…”

“…Dentro de los factores que podrían haber influido en la baja parasitosis en los roedores de los mercados en comparación con los roedores de granjas porcinas y zoológico, así como con estudios previos en mercados y otros ecosistemas de Lima, sería la presencia o ausencia de hospedadores intermediarios infectados en los mercados muestreados, el sistema inmunológico de las ratas y su baja densidad poblacional, considerando que un gran número de individuos genera un mayor hacinamiento y mayores probabilidades de infección (Kataranovski et al, 2011).…”