Deviance partitioning of host factors affecting parasitization in the European brown hare (Lepus europaeus)

Abstract

Deviance partitioning can provide new insights into the ecology of host-parasite interactions. We studied the host-related factors influencing parasite prevalence, abundance, and species richness in European brown hares (Lepus europaeus) from northern Spain. We defined three groups of explanatory variables: host environment, host population, and individual factors. We hypothesised that parasite infection rates and species richness were determined by different host-related factors depending on the nature of the parasite (endo- or ectoparasite, direct or indirect life cycle). To assess the relative importance of these components, we used deviance partitioning, an innovative approach. The explained deviance (ED) was higher for parasite abundance models, followed by those of prevalence and then by species richness, suggesting that parasite abundance models may best describe the host factors influencing parasitization. Models for parasites with a direct life cycle yielded higher ED values than those for indirect life cycle ones. As a general trend, host individual factors explained the largest proportion of the ED, followed by host environmental factors and, finally, the interaction between host environmental and individual factors. Similar hierarchies were found for parasite prevalence, abundance, and species richness. Individual factors comprised the most relevant group of explanatory variables for both types of parasites. However, host environmental factors were also relevant in models for indirect life-cycle parasites. These findings are consistent with the idea of the host as the main habitat of the parasite; whereas, for indirect life-cycle parasites, transmission would be also modulated by environmental conditions. We suggest that parasitization can be used not only as an indicator of individual fitness but also as an indicator of environmental quality for the host. This research underlines the importance of monitoring parasite rates together with environmental, population, and host factors.

Parasite load of European brown hares in Austria and the Czech Republic

“…A spontaneous and fatal jejunal intussusception in a brown hare associated with Eimeria leporis infection in Austria has also been reported (McCulloch et al 2004). Findings of coccidia in the Czech Republic and Austria (both the species spectrum and intensity of infection) are consistent with data published for other neighbouring countries (Czaplinska et al 1965;Gottschalk 1973;Pellerdy et al 1974;Barth and Brull 1975;Haupt and Hartung 1977;Nickel and Gottwald 1979;Soveri and Valtonen 1983;Alzaga et al 2009). …”

“…The prevalence of this parasite was reported to be 85% in Austria (Kutzer and Frey 1976) and 62 and 86% in the Czech Republic (Novak et al 1966;Pav 1978), with one to 1470 parasite specimens present in hosts. Reports from other European countries as well as from another species, Lepus timidus, were within the same range (Irvin 1970;Soveri and Valtonen 1983;Newey et al 2005;Alzaga et al 2009). Contrary to most of the above-mentioned studies, Pav et al (1981) and Grafner (1986) reported a relatively high prevalence and intensity of infection by the gastric nematode Graphidium strigosum (25-42 and 44.9%, respectively).…”

“…European brown hares may be infected with the lancet fluke Dicrocoelium dendriticum in areas with sheep at pasture (Graber and Lebrette, 1971;Gottschalk, 1973;Yanchew, 1973;Soveri and Valtonen, 1983;Alzaga et al 2009). Infection by the liver fluke Fasciola hepatica was reported by Kutzer and Frey (1976), Nickel and Gottwald (1979) and Tropilo (1964).…”

Lepus corsicanus gastro-intestinal helminths: first report

“…retortaeformis, G. strigosum, Trichuris sp. and C. pectinata are common parasites of lagomorphs and have been reported in Europe both in L. europeus (Canestri Trotti et al, 1988;Bordes et al, 2007;Alzaga et al, 2009;Dubinský et al, 2010) and in O. cuniculus (Giannetto et al, 1998;Sorgi et al, 2004;Eira et al, 2007). High frequence and abundance of T. retortaeformis and G. strigosum are usually reported in L. europaeus and the present paper indicates their importance also in L. corsicanus.…”

Endoparasites found in European brown hares (Lepus europaeus) hunted in Macedonia, Greece

“…Infectious diseases such as European brown hare syndrome (EBHS), pasteurellosis, yersiniosis and tularaemia represent an additional threat to L. europaeus (Lamarque et al, 1996). Parasites can also be one of the natural regulative factors of hare population (Newey et al, 2004;Alzaga et al, 2008). The information about the species and prevalence of endoparasites of European hares in Southern Europe is limited, while relevant data from Greece are lacking.…”