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Growing populations of Wild Turkeys (Meleagris gallopavo) may result in increased disease transmission among wildlife and spillover to poultry. Lymphoproliferative disease virus (LPDV) is an avian retrovirus that is widespread in Wild Turkeys of eastern North America, and infections may influence mortality and parasite co-infections. We aimed to identify individual and spatial risk factors of LPDV in Maine's Wild Turkeys. We also surveyed for co-infections between LPDV and reticuloendotheliosis virus (REV), Mycoplasma gallisepticum, and Salmonella pullorum to estimate trends in prevalence and examine covariance with LPDV. From 2017 to 2020, we sampled tissues from hunter-harvested (n=72) and live-captured (n=627) Wild Turkeys, in spring and winter, respectively, for molecular detection of LPDV and REV. In a subset of captured individuals (n=235), we estimated seroprevalence of the bacteria M. gallisepticum and S. pullorum using a plate agglutination test. Infection rates for LPDV and REV were 59% and 16% respectively, with a co-infection rate of 10%. Seroprevalence for M. gallisepticum and S. pullorum were 74% and 3.4%, with LPDV co-infection rates of 51% and 2.6%, respectively. Infection with LPDV and seroprevalence of M. gallisepticum and S. pullorum decreased, whereas REV infection increased, between 2018 and 2020. Females (64%), adults (72%), and individuals sampled in spring (76%) had higher risks of LPDV infection than males (47%), juveniles (39%), and individuals sampled in winter (57%). Furthermore, LPDV infection increased with percent forested cover (β=0.014±0.007) and decreased with percent agriculture cover for juveniles (β=–0.061±0.018) sampled in winter. These data enhance our understanding of individual and spatial predictors of LPDV infection in Wild Turkeys and aid in assessing the associated risk to Wild Turkey populations and poultry operations. [ABSTRACT FROM AUTHOR]

The monitoring of infectious diseases in wildlife is crucial for assessing animal health, pathogen range expansion, and the risk of spillover to naive species, but may be resource and labor intensive. Lymphoproliferative disease virus (LPDV) is an avian oncogenic retrovirus that was first identified in wild turkeys (Meleagris gallopavo) in 2009, though it historically caused mortality in domestic turkeys in Europe and Israel. Subsequent surveys detected a high prevalence and broad distribution throughout the eastern United States, warranting further research on LPDV in wild turkey populations. Current LPDV diagnostics require the collection of tissues, such as bone marrow from dead birds or blood during live capture. In our study, we assessed the sensitivity (true positive) and specificity (true negative) of cloacal swab samples as an alternative LPDV detection method. We compared results from cloacal swab samples with both postmortem detection from bone marrow and antemortem detection from blood, using a multi‐tube PCR approach with 3 replicates. Swab samples collected from live‐captured turkeys had a greater sensitivity (88%) than swabs collected from hunter‐harvested turkeys (31%), whereas specificity was similar for both collection approaches (live‐capture swabs = 75%, n = 85; hunter‐harvest swabs = 80%, n = 54). In live‐captured turkeys, the estimated LPDV prevalence using cloacal swab samples (73%) was not significantly different from the true prevalence determined using coupled blood samples (76%). However, in hunter‐harvested turkeys, the estimated prevalence using cloacal swab samples (28%) was different from the true prevalence estimated using coupled bone marrow samples (72%). In summary, cloacal swab samples can be used to reliably detect LPDV infection in live‐captured wild turkeys but should not be used for LPDV detection in hunter‐harvested wild turkeys. [ABSTRACT FROM AUTHOR]