Morley R S, Hugh-Jones M E
Agriculture Canada, Ottawa, Ontario.
Vet Res Commun. 1989;13(4):297-305. doi: 10.1007/BF00420837.
Incidence rates for clinical anaplasmosis were estimated for dairy and beef cattle in the Red River Plains and South-east areas of Louisiana. Annual incidence rates of 0.33% and 0.21% were found in dairy cows for 1983 and 1984 while a 31.0% rate was found in beef cows for 1983. The rates were based on postal surveys of dairy and beef cattle producers. A survey of veterinary practices and a follow-up of respondents to the surveys provided a description of 256 cases of anaplasmosis. Eighty-one percent of the clinical cases occurred in cattle aged 4-6 years and 88% of the cases occurred during the months of July-September.
对路易斯安那州红河平原和东南部地区的奶牛和肉牛临床无形体病的发病率进行了估计。1983年和1984年奶牛的年发病率分别为0.33%和0.21%，而1983年肉牛的发病率为31.0%。这些发病率是基于对奶牛和肉牛养殖户的邮政调查得出的。对兽医诊所的一项调查以及对调查受访者的跟踪提供了256例无形体病病例的描述。81%的临床病例发生在4至6岁的牛身上，88%的病例发生在7月至9月期间。
