Refuge Notebook • Vol. 19, No. 49 • December 8, 2017

Alaskan wild sheep and goats threatened by “Movi” by Dom Watts

More than 30% of the population in Gardiner, Montana, died from pneumonia caused by ovipneumoniae (credit: Deby Dixon).

Mycoplasma ovipneumoniae isn’t a commonly used cause significant respiratory disease in domestic an- name in Alaska but this little pathogen has been a topic imals, it may predispose individuals to more serious of considerable discussion and debate recently. First illness. This is often caused by concurrent infections of off, Mycoplasma ovipneumoniae isn’t very fun to spell, Movi and other equally difficult-to-spell bacterial flora, so let’s just call it “Movi.” such as Mannheimia haemolytica and Pasteurella mul- Second, you’re probably wondering just what tocida, species that naturally occur in the upper respi- Movi is and why it’s important. It’s a bacterium that ratory tracts of sheep and goats. commonly lives in the upper respiratory tracts of do- In healthy animals, these are typically mestic sheep and goats, often causing mild respiratory held in check by the body’s normal immune defenses disease. Infections in adults are typically not severe as antibodies destroy and slow the replication of these but young individuals, those in poor physical condi- bacteria. Movi infection, however, can suppress nor- tion, or those under stress may develop acute or fatal mal defense mechanisms and increase demands on an pneumonia. animal’s immune system. Ultimately, this diminishes Although Movi infection doesn’t always directly the animal’s resistance to Mannheimia and Pasteurella

USFWS Kenai National Wildlife Refuge 99 Refuge Notebook • Vol. 19, No. 49 • December 8, 2017 bacteria, facilitating the invasion of tissues and tic stock to wild populations. increasing the potential of fatal pneumonia. In Alaska, the risk of transmission between do- So Movi can make domestic sheep and goats sick, mestic stock and wild populations is much lower than but infected adults are often able to survive infec- in the western states where domestic grazing com- tions and can appear healthy. So what’s the big deal? monly occurs in wild habitats. One potential route for Sounds like an agricultural issue rather than a wildlife transmission of these diseases into wild populations is issue anyway, right? Well, Movi becomes a bigger via hunters using pack goats while hunting in alpine topic when it’s put in the context of wild sheep and habitats, which is why this activity is not allowed in mountain goat populations. Wild sheep and goats Alaska. The risk of transmission between livestock have little resistance to these bacteria that occur in near residences and wild populations in Alaska is cur- healthy domestic sheep and goats. rently unknown but interactions do occur. Given Since Movi has not been documented in wild pop- the potentially devastating impacts that might result ulations in Alaska, much of what we know about the from introductions, however, monitoring the preva- effects of this bacterium comes from the Lower 48and lence and distribution of Movi in both domestic and Canada. Movi has frequently been implicated in dra- wild populations throughout Alaska is certainly war- matic and large-scale die offs in Bighorn sheep popu- ranted. lations throughout the western states, with some pop- As part of continued state-wide monitoring, ulations experiencing declines of 75% or more due to mountain goats captured and fitted with radio-collars pneumonia outbreaks. Significantly reduced lamb sur- on the Kenai Peninsula during 2017 were tested for vival is often commonly reported for years following Movi. All goats tested were negative for Movi but outbreaks. Although we don’t know much about the continued monitoring is necessary, particularly on effects of Movi on Dall sheep or mountain goat popu- the Kenai Peninsula where the risk of introduction is lations, it seems reasonable to expect similar outcomes greater than in many other parts of Alaska. if Movi is introduced into Alaskan populations. The bottom line? Prevention is key. So inter- Like most bacteria that thrive in respiratory tracts, est groups from the agricultural community, private Movi is transmitted via aerosol and direct contact with owners, state and federal agencies, and other stake- infected individuals, the same way people transmit holders are currently working to develop a plan to colds to each other. The end result is that Movi can monitor Movi in domestic stock, with the goal of pre- easily be transmitted between infected domestic ani- venting the transmission of this and other harmful mals and wild populations if they come in contact. Al- micro-organisms to wild sheep and goat populations though infected domestic stock may appear healthy, in Alaska. they can still spread the bacteria to wild populations. Dom Watts is a Wildlife Biologist at Kenai Na- In some cases, Bighorn sheep die-offs have occurred tional Wildlife Refuge. Find more information about following interactions with domestic stock, further the Refuge at http://www.fws.gov/refuge/kenai/ or http: suggesting that Movi can be transmitted from domes- //www.facebook.com/kenainationalwildliferefuge.

100 USFWS Kenai National Wildlife Refuge