Vacuolar Myelinopathy in Waterfowl from a North Carolina Impoundment

US Fish and Wildlife Service, Ecological Services, Raleigh, North Carolina 27636-3726, USA.
Journal of wildlife diseases (Impact Factor: 1.36). 05/2003; 39(2):412-7. DOI: 10.7589/0090-3558-39.2.412
Source: PubMed


Vacuolar myelinopathy was confirmed by light and electron microscopic examination of mallards (Anas platyrhynchos), ring-necked ducks (Aythya collaris), and buffleheads (Bucephala albeola) collected during an epizootic at Lake Surf in central North Carolina (USA) between November 1998 and February 1999. Clinical signs of affected birds were consistent with central nervous system impairment of motor function (incoordination, abnormal movement and posture, weakness, paralysis). This is the first report of this disease in wild waterfowl (Anseriformes).

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Available from: Kimberli Miller, Aug 06, 2014
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    • "Impaired coots were collected during late fall from Woodlake (NC), Thurmond Lake (SC/GA), and Lake Juliette (GA) and histological examinations documented the characteristic AVM brain lesions. Wing clipped sentinel birds (wild American coots and game farm mallards Anas platyrhynchos Linnaeus 1758: 125) released at a North Carolina reservoir during a late fall mortality event became neurologically impaired within as few as five days (Rocke et al. 2002, Augspurger et al. 2003). Mallards housed in an off-site research facility with AVM-afflicted coots did not become neurologically impaired or develop "
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    • "Ultrastructurally, vacuolation is due to splitting of myelin lamellae at the intraperiod line, consistent with intramyelinic edema. These lesions result in variable neurologic dysfunction that in severe cases can result in death within a few days [2]–[4], [10]. "
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