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Avian vacuolar myelinopathy (AVM) is a fatal neurological disease that affects various waterbirds and raptors. It is most common in the bald eagle and American coot, and it is known in the killdeer, bufflehead, northern shoveler, American wigeon, Canada goose, great horned owl, mallard, and ring-necked duck.〔(【引用サイトリンク】url=http://www.nwhc.usgs.gov/disease_information/avian_vacuolar_myelinopathy/ )〕 Avian vacuolar myelinopathy is a newly discovered disease that was first identified in the field in 1994 when dead bald eagles were found near DeGray Lake in Arkansas in the United States. Since then, it has spread to four more states and infested multiple aquatic systems including 10 reservoirs.〔(【引用サイトリンク】url=http://www.forestry.uga.edu/swilde/ )〕 The cause of death is lesions on the brain and spinal cord, but the exact causative agent is still being investigated by researchers.〔 An infectious cyanobacterium is suspected. ==Clinical signs== Clinical signs have been recorded from research studies where individual birds were intentionally infected with the disease and from wild specimens and dead birds recovered from the field. Clinical signs listed are also those observed in American coots. *Raptors have been seen flying into objects, such as trees and rock faces *Waterfowl swim awkwardly, sometimes on their backs *Lack of coordination in flying and walking, sometimes dragging wings or one leg *Waterfowl crash land into water *Tremors of the head *Weight loss *Unresponsiveness to noise *Limb weakness *Beak and tongue weakness *Decreased pain response Most of the bald eagles have been found deceased from October to March, while the death count peaks during mid-November through December.〔 The waterfowl migrate to the area in October and November, where they consume the bacteria off of plants and become infected.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Avian vacuolar myelinopathy」の詳細全文を読む スポンサード リンク
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