Mycoplasma ovipneumoniae - A Primary Cause of Severe Pneumonia Epizootics in the Norwegian Muskox (Ovibos moschatus) Population

Abstract

The Norwegian muskox (Ovibos moschatus) population lives on the high mountain plateau of Dovre and originates from animals introduced from Greenland. In the late summers of 2006 and 2012, severe outbreaks of pneumonia with mortality rates of 25-30% occurred. During the 2012 epidemic high quality samples from culled sick animals were obtained for microbiological and pathological examinations. High throughput sequencing (pyrosequencing) of pneumonic lung tissue revealed high concentrations of Mycoplasma ovipneumoniae in all six animals examined by this method and Pasteurella multocida subsp. multocida in four animals, whereas no virus sequences could be identified. Mycoplasma ovipneumoniae and P. multocida multocida were also isolated by culture. Using real time PCR on lung swabs, M. ovipneumoniae was detected in all of the 19 pneumonic lungs examined. Gross pathological examination revealed heavy consolidations primarily in the cranial parts of the lungs and it also identified one case of otitis media. Histologically, lung lesions were characterized as acute to subacute mixed exudative and moderately proliferative bronchoalveolar pneumonia. Immunohistochemical (IHC) examination revealed high load of M. ovipneumoniae antigens within lung lesions, with particularly intensive staining in the neutrophils. Similar IHC finding were observed in archived lung tissue blocks from animals examined during the 2006 epidemic. An M. ovipneumoniae specific ELISA was applied on bio-banked muskox sera from stray muskoxen killed in the period 2004–2013 and sick muskoxen culled, as well as sera from wild reindeer (Rangifer tarandus tarandus) on Dovre and muskoxen from Greenland. Serology and mycoplasma culturing was also carried out on sheep that had been on pasture in the muskox area during the outbreak in 2012. Our findings indicated separate introductions of M. ovipneumoniae infection in 2006 and 2012 from infected co-grazing sheep. Salt licks shared by the two species were a possible route of transmitting infection.

Anti-BrucellaAntibodies in Moose (Alces alces gigas), Muskoxen (Ovibos moschatus), and Plains Bison (Bison bison bison) in Alaska, USA

“…9,462.563,143.6 9,000 5,750 6,585.962,310.6 6,125 4,750 Eosinophils/lL 2,230.661,287.3 1,656 Another condition that appeared to contribute to morbidity and mortality was verminous, bacterial, or aspiration pneumonia. Multifactorial pneumonia, including contributing pasteurellosis has caused mortality in Norwegian muskoxen during extreme weather events (Ytrehus et al 2008), and recently, M. ovipneumoniae has been suggested as the primary cause of a severe pneumonia outbreak in Norwegian muskoxen (Handeland et al 2014). In our study, culture and IHC of lung tissues with pneumonia that were negative for M. bovis.…”

“…In 2004, this population experienced a severe contagious ecthyma (CE) outbreak (Vikøren et al 2008), and in 2006, a multifactorial outbreak of pneumonia occurred during extreme weather events and caused mortality of up to 26% (Ytrehus et al 2008(Ytrehus et al , 2015. In 2012, Mycoplasma ovipneumoniae was the primary cause of a severe pneumonia outbreak (Handeland et al 2014). Recently, Erysipelothrix rhusiopathiae was identified as a significant cause of mortality (Kutz et al 2015) in Canadian muskoxen.…”

Pneumonia in bighorn sheep: Risk and resilience

“…are host-specific, and the host range of M. ovipneumoniae is considered to be limited to Caprinae . Respiratory disease following infection with M. ovipneumoniae also has been reported in captive Dall's sheep and other wild Caprinae, including mountain goats (Oreamnos americanus), and muskox (Ovibos moschatus; Black et al 1988, Handeland et al 2014. In a recent National Animal Health Monitoring System survey, Sheep 2011, the Animal and Plant Health Inspection Service tested up to 16 adult females each in 453 randomly selected domestic sheep flocks from across the United States for M. ovipneumoniae nasal carriage and serum antibody.…”

Investigation of severe coughing and ill thrift in adult hill sheep associated with Mycoplasma ovipneumoniae

“…An indirect ELISA developed in-house was used to test sera from sheep in the flock (Handeland and others 2014). Sera were diluted 1/100 and applied to microtitre plates coated with whole M. ovipneumoniae cells optimised previously by chequerboard titration.…”