High seroprevalence of Toxoplasma gondii in elk (Cervus canadensis) of the central Appalachians, USA

Abstract

Toxoplasma gondii is an important protozoan parasite of mammals that impacts animal health and behavior. Although this parasite has been documented in several cervid species, including red deer (Cervus elaphus) in Europe, little is known about T. gondii impacts on the closely related North American counterpart, the elk (wapiti, Cervus canadensis), which has increased in number and expanded in range during the past century. We assessed seroprevalence of T. gondii antibodies using a modified agglutination test (MAT) (1:25 titer) and blood collected from 142 free-ranging elk in Kentucky, USA, where the species was reintroduced during 1997-2002 after over a century of absence. Eighty of 142 (56.3%) elks were seropositive for T. gondii, but we found no infection or titer differences between sexes (U = 2146, P = 0.128). However, odds of T. gondii infection significantly increased with elk age (β = 0.429, P = 0.001) by a factor of 1.54 (95% CI 1.19-1.99), and titer increased commensurate with age (JT = 3071, P < 0.001). High prevalence of T. gondii infection in elk of this region may be explained by sympatry with two primary hosts, the bobcat and domestic cat, as well as shed oocysts in the soil of this relatively wet and humid region. We suggest that wildlife agency personnel incorporate warnings about proper elk meat preparation into their hunter education outreach programs and literature to reduce the chances for human infection from consuming contaminated venison.

The influence of exposure to Toxoplasma Gondii on host lipid metabolism

“…One thousand forty-five healthy individuals (mean age = 47.29 ± 13.8 years old) were enrolled in this study. The rate of T. gondii seropositivity in the entire sample was 8.51% (89/956), which was within the range of the estimated infection rate in China and several other countries [23][24][25]. Demographics and clinical features of the participant samples by anti-T. gondii IgG status (positive or negative) are presented in Table 1.…”

“…The association of T. gondii seropositive and different lipid indexes was analyzed with the rank sum test. We calculated the sample with a reference seroprevalence of 8 to 22% [23] as the expected frequency of exposure in T. gondii seropositive groups. We calculated the odds ratio (OR) and 95% confidence interval (CI).…”

Mortality, Survival, and Serologic Results for Elk (Cervus Canadensis) in the Cumberland Mountains of Tennessee, Usa

“…A cutoff value of ≥1:25 was considered seropositive (Su and Dubey 2020). Although this MAT has not been validated for elk diagnostics, it has been extensively tested in cervids and is considered specific regardless of the species (Dubey 2010; Cox et al 2017).…”

Toxoplasmosis in wild and domestic animals

“…Antibodies to T. gondii were detected in sera of 221 of 317 (69.7%) elk from Pennsylvania collected during 2013À16 hunting season by the MAT and hearts from 2 of 20 elk were positive by bioassay (Dubey et al, 2017). Eighty of 142 (56.3%) elk from Kentucky were seropositive for T. gondii (Cox et al, 2017).…”