1909.] 



Amakebe : A Disease of Calves in Uganda. 



269 



disease has been shown to be caused neither by Firoplasma higeminum nor 

 Firoplasma uiutans. What, then, is it caused by ? 



Examination of the Blood in Amakebe. 



When the blood of an animal suffering from Amakebe is examined, many 

 small piroplasms will be seen (Plate 10, fig. 3), which appear to be of the 

 same size and shape as Firoplasma mutans, and sometimes a few Firoplasma 

 higeminum ; otherwise, no new parasite can be said to have come into the 

 blood. This increase in the number of the small piroplasms in the blood of 

 a calf suffering from Amakebe may be explained by saying that the severe 

 illness has led to an excessive multiplication of the Piroplasm,a mutans which 

 was already in the blood. Or, on the other hand, it may be that another 

 species of piroplasm, similar in size and shape to Firoplasma mutans, has 

 appeared in the blood, and that the phenomena of Amakebe are due to it. 



Marginal Foints. — Besides the large and small piroplasms, another kind of 

 body is found m the red blood corpuscles, which Theiler has called marginal 

 points. In a lecture delivered by him in August, 1909, at Nairobi, in British 

 East Africa, and published in the ' Agricultural Journal of British East Africa,' 

 October, 1909, he states : " I have recently come to the conclusion that the 

 disease called gall-sickness, and hitherto looked on as a sequel of redwater, is 

 due to the presence of another parasite, which I have called ' Marginal 

 Points ' owing to their position in the red blood corpuscles. Gall-sickness is, 

 therefore, a separate and distinct disease." Dr. Theiler considers it proved 

 that this new disease is transmitted by the blue tick. This all shows how 

 complicated and difhcult to distinguish are the diseases of cattle. An ox may 

 have Firoplasma higeminum, small rod-and-ring-shaped piroplasms, marginal 

 point§, and one or two species of trypanosome in its blood at the same 

 time. To which parasite have the different phenomena of the disease to be 

 credited ? 



The two following tables give the blood examination in two cases of Amakebe, 

 and illustrate this complexity. 



The marginal points are small, deeply-staining bodies, usually placed near 

 the edge of a red blood corpuscle (Plate 10, fig. 3). If these bodies really consti- 

 tute a new and undescribed parasite, the discovery will be one of the greatest 

 interest. Bodies similar in every way to these are found, however, in healthy 

 young rats, goats, calves, etc., so that it is difficult to believe at once in 

 their parasitic nature. Eather would they appear to be cell enclosures, due 

 to rapid changes taking place in the blood, such as take place in young 

 animals or in ansemias. In Amakebe they are sometimes very numerous, and 

 it requires no great stretch of the imagination to see in them the youngest 



