ANAPLASMA-OVIS IN IDAHO SHEEP

  • 1 January 1981
    • journal article
    • research article
    • Vol. 42  (2) , 199-201
Abstract
Blood samples from 16 anaplasmosis complement-fixation (CF) positive sheep from a flock near Cambridge, Idaho, were inoculated into 3 intact sheep and 3 splenectomized calves. The 3 sheep became CF positive and 2 developed parasitemia. None of the 3 calves had signs of anaplasmosis, but all became ill when they were subsequently challenge exposed with blood from known carriers of A. marginale. After a 75 day observation period, blood from the recipient intact sheep was subinoculated into 3 splenectomized sheep. These splenectomized sheep developed clinical anaplasmosis and became CF positive. In only 1 sheep was there a positive rapid card agglutination test. The rapid card agglutination test was thus not considered to be diagnostic for anaplasmosis carrier status in sheep. EM studies were performed on infected sheep erythrocytes to determine the morphologic structure of the organism involved. The causative organism was determined to be A. ovis.