Mortality and Disease in Wild Turkeys (Meleagris gallopavo silvestris) in Ontario, Canada, from 1992 to 2014: A Retrospective Review

Abstract

Wild turkeys ( Meleagris gallopavo silvestris) were extirpated from Ontario, Canada, in the early 1900s due to unregulated over-hunting and habitat loss. Despite a successful reintroduction program and strong population numbers, information regarding the health of wild turkeys in Ontario is scarce. A 22-yr (1992-2014) retrospective study was performed to evaluate diagnostic data, including the cause(s) and contributors to death, in wild turkeys submitted to the Ontario-Nunavut node of the Canadian Wildlife Health Cooperative (n = 56). Noninfectious diagnostic findings (39/56; 69.6%) were more common than infectious, with emaciation recognized most frequently (n = 19; 33.9%) followed by trauma (n = 11, 19.6%). The majority of deaths due to emaciation occurred in winter and spring (17/18; 94.4%), which is consistent with lack of access to or availability of food resources. Morbidity and mortality due to infectious diseases was diagnosed in 16 (28.6%) wild turkeys. Avian poxvirus was the most common infectious cause of disease (n = 7; 12.5%), followed by bacterial infections (n = 5; 8.9%), the most common of which was Pasteurella multocida . Zinc phosphide toxicosis (n = 7; 12.5%) occurred in two incidents involving multiple birds. This study aims to provide baseline data that can be used for reference and comparison in future wild turkey disease surveillance and population monitoring studies.