Wild Turkeys (Meleagris gallopavo spp.) are a popular game bird in North America. Populations in many states in the US have been declining due to unknown causes. Concern about potential impacts of disease on Wild Turkeys has been increasing. Lymphoproliferative disease virus (LPDV) is an avian retrovirus initially identified in domestic turkeys in Europe and Israel that often presented as lymphoid tumors and was associated with high mortality rates. In 2009 LPDV was first reported in the US and has been reported in numerous US states and Canadian provinces, though little is known about its effects on Wild Turkey populations. Our objective was to identify prevalence and spatial patterns of LPDV infection in Wild Turkeys in Iowa, USA. We tested bone marrow from 912 Wild Turkeys that were hunter-harvested (n=907), road-killed (n=3), or submitted for necropsy (n=2) for LPDV. Samples were collected between 2019 and 2021, but comprised primarily adult males from the 2020 spring harvest. We found that LPDV was distributed across Iowa, with an estimated statewide prevalence of 42.9%. Cluster analysis using Kulldorff's spatial scan statistic identified two clusters of higher prevalence (hotspots) and two clusters of lower prevalence (coldspots) than expected. The Iowa landscape is dominated by agriculture (81%) with a smaller amount of forest (7%). The two hotspots were located within some of the more heavily forested portions of the state (16.6% and 7.9% forest), while the coldspots had smaller amounts of forest (3.8% and 0.8%). Our results provide the first information on the prevalence and distribution of LPDV in Iowa and could be used to identify areas to prioritize continued surveillance as well as conduct research on the effects of LPDV on Wild Turkey populations.
Smith et al. (Thu,) studied this question.