In October and November, 1982, three cows were affected with a disease with dysphagia as a main symptom in Saga Prefecture in the Kyushu region. They also suffered from salivation, vomiting, and mild pyrexia and died in 7 to 10 days. Autopsy revealed ulceration on the ventral surface of the tongue, scattered white spots on the mucosal surface of the esophagus, and hyperemia and ulceration on the mucosa of the abomasum. Histological changes noticed were coagulation necrosis of muscle fibers in the tongue, esophagus, and heart and necrosis and ulceration on the ventral mucosal surface of the tongue, Virus isolation was negative when it was tried in blood samples collected from one of the affected cows and one of six cows housed in the same barn as the affected ones, but in vain. Neutralizing antibody against Ibaraki virus was detected from all the affected cows and five of the 6 exposed ones. As a result, the disease was diagnosed as Ibaraki disease, the last outbreak of which was in 1960 in Japan.
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