Wild turkeys are not scapegoats for avian disease

A LOT OF ANGST is simmering in farm circles about the potential for disease to spread between wildlife and domestic livestock, such as poultry. The concerns are warranted, given how quickly disease can race through a herd and create huge losses.

But new research from the University of Guelph into the health status of Ontario wild turkeys (Meleagris gallopavo silvestris) – which many producers in the province welcomed onto their farm during the birds’ reintroduction here in the 1980s – has given this species a clean bill of health. Here’s what happened. A postmortem study was conducted on 152 wild turkeys, provided by hunters during a one-month period in the spring of 2015, to pathobiology graduate student Amanda MacDonald and Prof. Nicole Nemeth of the Ontario Veterinary College.

The results showed either no amount or only marginal amounts of many of the disease-causing agents that can lead to some of the more wellknown, and nasty, diseases that also affect domestic

turkeys.

These diseases include avian influenza, one of the most feared diseases in poultry production. The researchers found no incidence of it in the wild turkeys in their study, nor any salmonella.

Some other disease agents were detected in minute quantities, such as Campylobacter and avian poxvirus.

And one case of antibiotic-resistant bacteria was found.

E.coli was shed by about three-quarters of the birds. But it was the standard form of the bacteria that is common in the digestive tracts of humans and other animals.

Mycoplasma and coccidia were also commonly found, in additional tests conducted in collaboration with the research lab of the veterinary college’s Prof. John Barta, and the Animal Health Laboratory at the University of Guelph. So was reticuloendotheliosis virus (REV) and lymphoproliferative disease virus (LPDV). However, in general, these potential disease-causing agents didn’t seem to be causing any disease, either.

“Overall, the wild turkeys we examined appeared to be in good health,” says Nemeth, who along with Barta is part of the university’s Poultry Health Research Network. “We now have a good snapshot of the potential disease-causing organisms that may be carried by healthy-appearing wild turkeys in Ontario.”

That’s good news for producers, hunters and anyone who appreciates ecological diversity. Wild turkeys mostly disappeared in Ontario in the early 1900s, due to unregulated over-hunting and habitat loss. But a successful reintroduction program by the Ontario Ministry of Natural Resources, National Wild Turkey Federation and the Ontario Federation of Anglers and Hunters, saw their numbers soar.

The most recent count, from 2007, puts the population at around 70,000. But despite these numbers, information about the wild turkeys’ health status is scarce.

With such a high population, the Ontario Ministry of Agriculture, Food and Rural Affairs, which sponsored MacDonald’s and Nemeth’s study, was anxious to see if the prolific wild birds were harbouring disease, and likely to cause problems with their domestic counterparts – or vice versa.

But so far, this doesn’t seem to be the case.

“From a wildlife health perspective, it is really encouraging to see that wild turkeys in Ontario appear to be doing well and hopefully, will continue to have sustainable populations,” says MacDonald.