Anaplasmosis survey in northern California, 1969-1970: prevalence of complement-fixing antibodies in cattle by herd location
Utterback, W.W.; Stewart, L.M.; Beals, T.L.; Franti, C.E.
American Journal of Veterinary Research 33(1): 257-267
1972
ISSN/ISBN: 0002-9645 PMID: 5062010 Document Number: 46159
The CF test was used to identify carriers among 8892 cattle-mainly beef cattle over 2.5 years old. Data were analysed with respect to ecological and management factors, in order to find the variables most useful in predicting prevalence. There were:- use of foothill and mountain pasture, density of cattle and deer on pasture, source of replacement stock, and presence of insect vectors. The prevalence in dairy herds maintained mainly on fenced valley pasture was 7%, compared with 40-70% in neighbouring beef herds grazed on upland pastures and exposed to deer and ticks. Taking these factors into account, the prevalence in a herd could often be predicted. The overall prevalence in northern California was 40%.