Microbiological Study of Wild Turkeys

Wild and domestic turkeys are susceptible to a number of infectious diseases. Over the last thirty years repopulation of wild turkeys in Maine has put these animals in close contact with hunters, livestock, and agricultural workers. Wild birds can carry a range of microbial agents that may contribute to the dissemination of pathogens that are harmful for livestock and human health. In addition, the health of the wild turkey population itself is of interest to recreational hunters, and Maine Inland Fisheries and Wildlife for management and economic reasons.

Over the last two years 70 live and 55 dead or euthanized wild turkeys were sampled for exposure to a wide variety of pathogens. Screening included tests for common poultry pathogens such as salmonella, Mycoplasma species, avian influenza, and blood parasites. In addition, microbial isolation of staphylococci was performed, as well as tests for viral pathogens including Avian Pox Virus (APV), Eastern Equine Encephalitis Virus (EEEV), West Nile Virus (WNV), and Lymphoproliferative Disease Virus (LPDV).

Our results show that Maine wild turkeys have a high prevalence of Mycoplasma exposure and Leukocytozoon blood parasites in our samples. While incidence of Mycoplasma infection in commercial poultry in the US has been lowered over the last 50 years, backyard and free range poultry flocks are susceptible. Leukocytozoon parasites are transmitted through black flies and wild turkeys are a reservoir for L. smithi in areas that produce commercial turkeys. High incidence compared to domestic animals is expected (figure 1).

Isolation of Staphylococci species from the nares of wild and domestic turkeys in Maine has shown that Methicillin-Resistant Staphylococcus aureus (MRSA) exists in both populations in Maine (Figures 2a and 2b). The importance of community and livestock acquired MRSA in hospitals is on the rise globally. Further studies are ongoing to classify and compare isolates in the lab.

The discovery of a new cancer causing virus (LPDV) in eastern wild turkeys in 2009 by researchers working with the Southeastern Cooperative Wildlife Disease Study may have implications for the health of wild turkeys in the eastern United States. Discovery of LPDV in 12 out of 15 Maine wild turkeys with obvious signs of disease in 2012 was the first indication that this virus was in Maine (Figure 3). Expanded studies are ongoing to evaluate the extent of infection in Wild Birds and effect on the domestic Turkeys in Maine.