著者
一条 茂 小野 悌二 本多 道明
出版者
公益社団法人 日本獣医師会
雑誌
日本獣医師会雑誌 (ISSN:04466454)
巻号頁・発行日
vol.12, no.3, pp.106-110, 1959-03-20 (Released:2011-06-17)
参考文献数
8

In a certain animal farm in the Tokachi district of Hokkaido, 10 sheep which were housed in the same shed were attacked one after another, in the fall of 1956, by a febrile disease with anemia and hemoglobinuria as its principal symptoms. The investigation of the affected animals made it clear that this disease was piroplasmosis which had been reported very little in Japan.The symptoms revealed on these cases consisted of anemia, jaundice, hemoglobinuria, pyrexia of about 40.5°C, and lumbar paralysis. In the hematological examination, organisms of Piroplasma, pear-and twin-pear-shaped, spherical, and rodlike, were demonstrated in red blood corpuscles.When inoculated intravenously with the blood drawn from the infected animals, healthy sheep ran fever at about 40.5°C for 3 to 13 days after inoculation, showing remittent fever. Since the onset of fever, anemia became gradually conspicuous, the erythrocyte count dropping to 4 million on the 10 th day. With the advancement in anemia, a remarkable polychromasia and basophilic petechiasis of erythrocytes, erythroblasts, pessary corpuscles, and reticulocytes appeared. Piroplasma was also demonstrated. The urine gave positive tests of protein, hemoglobin, and sugar. In general, the symptoms were almost the same with those manifested by the animal naturally infected.With these observations in mind, the authors performed an epizootiological survey on this outbreak of piroplasmosis. The results indicate that the initial case was a breeding ram which was imported in Japan from New Zealand in 1953 and which might have been infected with this disease by ticks, acting as vectors, while it was grazed with some infected sheep in the meadow where the ticks were prevailing. It was possible that this ram had been in the state of carrier of the protozoa when it was brought into Japan.