Free-Ranging Eurasian Lynx (Lynx Lynx) as Host of Toxoplasma Gondii in Finland

Abstract

ABSTRACT:We investigated the presence of Toxoplasma gondii infections in Eurasian lynx (Lynx lynx) in Finland by analyzing samples from 337 lynx that were legally hunted during the 2010-2011 season and by performing a retrospective nationwide database search of postmortem toxoplasmosis diagnoses in this species. We detected specific anti-T. gondii IgG antibodies in 290 (86.1%) of the 337 lynx. The method used was a direct agglutination test, and samples positive at the used dilution 1:40 were defined as antibody positive. Older lynx had 14.3 times higher odds of being antibody-positive than did lynx of the presumed age of 7-10 mo, and lynx weighing .15 kg had 16.7 times higher odds of being antibody positive than did those #15 kg. Lynx from the southwest were more often antibody positive, with an odds ratio 6.3, than lynx from the northeast. None of the 332 fecal samples available was positive for the presence of T. gondii-like oocysts with a quantitative MgSO 4 flotation technique, and none of the 167 free-ranging Eurasian lynx examined postmortem by veterinary pathologists from January 2000 to May 2010 had died from toxoplasmosis. Although Finnish lynx were confirmed to commonly encounter T. gondii, we found no evidence of an ongoing contribution to the environmental oocyst burden nor of the lynx dying from the infection.

Toxoplasma gondii seroprevalence varies by cat breed

“…How cats are kept varies around the world, and T. gondii infection pressure varies between and within countries. In Finland, a geographical north-south gradient in T. gondii seroprevalence has been described in Eurasian lynx (Lynx lynx) [27], and in moose (Alces alces) and domestic sheep (Ovis aries) [28]. The lynxes that originated from the south-west of Finland had a significantly higher T. gondii seroprevalence than the lynxes from north-east [27].…”

“…In Finland, a geographical north-south gradient in T. gondii seroprevalence has been described in Eurasian lynx (Lynx lynx) [27], and in moose (Alces alces) and domestic sheep (Ovis aries) [28]. The lynxes that originated from the south-west of Finland had a significantly higher T. gondii seroprevalence than the lynxes from north-east [27]. Similarly, the seroprevalence in moose and sheep was higher in south-western and lower in northern parts of Finland [28].…”

“…Mammals, including humans, and birds can acquire T. gondii infection by ingesting sporulated oocysts, which have been shed in unsporulated form by infected felids. The only wild felid living in Finland is the Eurasian lynx (Lynx lynx), which has not been shown to shed T. gondii oocysts [27]. The domestic cat is considered to be the most important host species of T. gondii evolutionarily and also epidemiologically for example in regions where domestic cats outnumber the other definitive hosts [2,24,27].…”

“…The only wild felid living in Finland is the Eurasian lynx (Lynx lynx), which has not been shown to shed T. gondii oocysts [27]. The domestic cat is considered to be the most important host species of T. gondii evolutionarily and also epidemiologically for example in regions where domestic cats outnumber the other definitive hosts [2,24,27]. Most seropositive cats are considered to have previously shed oocysts in their feces [1].…”

Anatomical variations and pathological changes in the hearts of free-ranging Eurasian lynx (Lynx lynx) in Finland

“…Endo-and ecto-parasitic infections are common in Eurasian lynx populations, but the parasitic infections are rarely lethal or cause a clinical disease Ilona Kareinen and Emilia Lavonen contributed equally to this work. (Jokelainen et al 2013;Kołodziej-Sobocińska et al 2018). However, scientists from other parts of Europe have reported cardiovascular changes, especially from re-introduced subpopulations of the free ranging lynx, such as subaortic stenosis, arteriosclerosis and myocardial fibrosis, and surmise them as possible health hazards for the species (Ryser-Degiorgis et al 2004;Ryser-Degiorgis and Robert 2006).…”