The transmission of Anaplasma marginale and Anaplasma centrale to several species of South African antelopes was discussed by Neitz and du Toit (1932) and Neitz (1935). The experiments showed that A. marginale produced an active infection in the blesbuck, the duiker and the blackwildebeest, whereas A. centrale resulted in a latent infection in the blesbuck.
According to Lignières (1919) A. marginale produces a latent infection in sheep and goats. This observation in sheep was confirmed by Kraus, Dois and Oyarzabal (1922), Sergent, Donatien and Lestoquard (1924) and Neitz and du Toit (1932). Theiler (1910) and de Kock and Quinlan (1926), on the other hand, failed to infect sheep with A. marginale. Their experiments were carefully carried out, and it must therefore be concluded that sheep cannot always become infected with bovine anaplasmosis.
De Kock and Quinlan (1926) and Donatien and Lestoquard (1930) showed that cattle are not susceptible to A . ovis.
On account of the difference in the behaviour of the three species of anaplasma in the ruminants mentioned above, experiments were undertaken to ascertain the response of the blesbuck to A. ovis.