1911.] 



by means of Rhipicephalus appendiculatus. 



113 



On several occasions Mr. Hutchins forwarded me brown ticks, which he 

 had placed in a glass tube ; in every instance they arrived alive and in good 

 condition, having moulted in transit from the nymphal into the adult stage. 

 The first two lots of ticks failed to transmit the disease, the nymphse 

 probably having been collected off calves which had recovered from the 

 disease, when the blood no longer contained the pathogenic parasite. 

 Experiments with the last lot were successful, as will be shown hereunder. 



Experiment to note whether Brown Ticks collected as Xymphe in 

 Uganda from a Calf suffering from Amakebe will transmit the 

 Disease to Susceptible Calves in the Transvaal. 



(1) Bull calf 1118, born and reared in Onderstepoort, was infested on 

 January 23, 1911, with 10 adult brown ticks, forwarded by Mr. Hutchins 

 from Uganda and received here on January 4, 1911. All 10 ticks were 

 found attached to the calf the following day. 



The calf showed almost immediately a rise of temperature, developing 

 into a definite curve, during which the so-called marginal points (Anaplasma 

 marginale) were noted to be present in great numbers; this curve was 

 typical of the disease anaplasmosis, and the blood lesions found were 

 those of an oligocythaamia (anisocytosis, poikilocytosis, polychromasia and 

 basophilia) which followed as a sequel. The temperature gradually dropped, 

 and the calf was founds dead on the 22nd day after tick infestation. An 

 examination of the lymphatic glands was made on the 17th day, and a 

 negative result was registered. 



Post-mortem Examination on Calf 1118. — The condition was fair. Eigor 

 mortis was present. Tympanitis was noted. The lungs were partially collapsed 

 and showed some atelectatic areas. On section a slight oedema became 

 noticeable ; in the trachea was some foam. The bronchial lymphatic glands 

 were swollen, the mediastinal glands were normal. 



The pericardium contained some clear liquid. The blood in the ventricles 

 was well coagulated. Both endocards were normal. The liver was enlarged 

 and had a mottled appearance due to small pale areas ; the parenchyma 

 was soft. The periportal lymphatic glands were enlarged. The bile was 

 yellow and viscid. The spleen was enlarged, measured 30 cm. by 10 cm., 

 the pulp was softened, jam-like ; the trabeculae were indistinct. All four 

 stomachs were normal. 



The mucosa of the jejunum was slightly thickened and cedematous, that 

 of the caecum and colon was slate -coloured and contained a small number 

 of disseminated parasitic nodules. 



vol. lxxxiv. — B. I 



