Frimeth J P, Arai H P
Can Vet J. 1984 Jan;25(1):14-6.
A blood survey for the prevalence of the microfilariae of the canine heartworm, Dirofilaria immitis was conducted in the Calgary area of southern Alberta between November 1977 and August 1979. A total of 514 blood samples was examined by the modified Knott's test. All of the samples were negative for D. immitis microfilariae. Wright's stained blood smears taken from 19 animals at the Calgary Zoo also proved negative. One smear from a male two-toed sloth (Choloepus didactylus) contained sheathless microfilariae which were distinguishable from those of D. immitis. These results, as well as mail survey data indicate that D. immitis is not endemic in the Calgary area.It is recommended that the modified Knott's test be used for similar large scale sampling studies. In addition, it is suggested that the testing of both native and exotic zoo animals which could serve as definitive hosts of D. immitis be continued. These animals may become local sources of infection or introduce other species of microfilariae which will have to be differentiated from those of D. immitis.
1977年11月至1979年8月期间，在艾伯塔省南部的卡尔加里地区开展了一项血液调查，以了解犬心丝虫（犬恶丝虫）微丝蚴的流行情况。通过改良的诺氏试验对总共514份血样进行了检测。所有样本的犬恶丝虫微丝蚴检测结果均为阴性。从卡尔加里动物园的19只动物采集的经瑞氏染色的血涂片检测结果也为阴性。来自一只雄性二趾树懒（霍氏树懒）的一张涂片含有无鞘微丝蚴，这些微丝蚴与犬恶丝虫的微丝蚴不同。这些结果以及邮件调查数据表明，犬恶丝虫在卡尔加里地区并非地方病。建议将改良的诺氏试验用于类似的大规模抽样研究。此外，建议继续对可能作为犬恶丝虫终末宿主的本地和外来动物园动物进行检测。这些动物可能成为本地感染源，或引入其他种类的微丝蚴，而这些微丝蚴必须与犬恶丝虫的微丝蚴区分开来。
