SYMPTOMS AND DIAGNOSIS 33 



and the history of the case and of the farm on which 

 it occurs, are, as a rule, sufficient to differentiate the 

 two conditions. In the event of the discovery of 

 only a few of these parasites, it is well to make 

 film preparations from scrapings of the. mucosa of the 

 intestine, and to examine for acid-fast bacilli. 



Treatment of such cases is usually best carried out by 

 applications of lime or salt to the land and by proper 

 drainage. It is also recommended that young sheep 

 should not be allowed on land where old sheep have 

 recently been kept. 



CocciDiosis, Psorospermosis, Dysentere Rouge. — 

 These terms are all applied to the disease of cattle that 

 is caused by the Coccidium {Eimeria) bovis^ discovered 

 by Zurn in 1878. Cases have been reported in Great 

 Britain by Gair (1898); also in Switzerland, France, 

 Italy, Germany, East Africa, the Soudan, and the 

 United States of America. When it attacks adult 

 animals and assumes a chronic form, it may be mis- 

 taken for Johne's disease. We have seen this con- 

 dition described under the latter name in an American 

 agricultural journal. The chronic cases are, as a 

 rule, sporadic, but in young animals it occurs as an 

 enzootic. 



The coccidium oocyst, the form in which it is 

 most commonly met with in the faeces of cattle, is a 

 round or oval body measuring from 14 to 16 /x, or 

 in some cases from 20 to 30 ft (two to gw inch). 

 This is smaller than the Coccidium oviforme of the 

 rabbit, which is met with in many parts of Great 

 Britain. 



The cysts have " a highly resistant envelope, show- 

 ing a doubly contoured outline when viewed through 

 the microscope. In freshly voided faeces the contents 

 of the oocyst in many instances entirely fill the shell, 



3 



