INTESTINAL COCCIDIOSIS OF CALVES AND LAMBS. 273 



ovoid corpuscles having a double outline, and contents of varied 

 appearance ; these are the coccidia. 



When the diarrhoea has become sanguinolent and muco-fibrinous, the 

 fluid contains these coccidia in considerable quantities, and large numbers 

 of them may be found in the mucus, where they are mixed with epithelial 

 dehris, blood corpuscles, and lymphatic cells, etc. They are rarer in the 

 clots. Coccidia cannot be found in the f^ces of healthy animals, even in 

 those occupying the same pastures with the diseased. Should the clinical 

 symptoms be thought insufficient of themselves clearly to identify the 

 disease, a simple microscopic examination of the faeces will remove any 

 doubt. 



Lesions. Post-mortem examination immediately after death enables 

 one exactly to identify the habitat of the parasite and the lesions it pro- 

 duces. These lesions are to be found throughout the large intestine, 

 from the caecum to the anus. 



The large intestine is almost or entirely empty, the mucous membrane 

 is reddish-brown in colour, lies in folds, is cedematous, and everywhere 

 covered with a coating of mucus. This coating varies in character at 

 different points ; in places it forms more or less thickened patches of 

 greyish or yellowish colour, and of a resistant character, as though mixed 

 with coagulated fibrin. These patches are fairly well defined, they are 

 irregular in form, and vary in width from some millimetres up to several 

 centimetres. They are more or less adherent to the mucous membrane, 

 from which they can easily he stripped away. The mucous membrane 

 thus exposed is slightly depressed, and of a whitish colour, thus markedly 

 contrasting with the surrounding red coloration. This depression repre- 

 sents a slight ulceration, which, though superficial, is clearly visible to 

 the naked eye. 



Microscopic examination of the mucus patches reveals the existence, 

 both superficially and in the depths, of epithelial cells derived from the 

 mucous membrane, of vesicular cells derived from the Lieberkuhnian 

 follicles, of numerous blood and lymphatic corpuscles, and, distributed 

 irregularly throughout this mass of cells, of coccidia, resembling those 

 found in the dejections. 



In thin sections of the intestine, made through the ulcerated mucus- 

 covered patches, and in a direction perpendicular to the mucous 

 membrane, one finds that the epithelial covering of the intestine has 

 disappeared. 



The Lieberkuhn's follicles are shortened, their orifices are irregular 

 and partly blocked with epithelial debris. In a large number of these 

 follicles the blind extremity is dilated, and more or less filled with coccidia, 

 varying in appearance according to their stage of development. The 

 epithelial cells normally lining these blind ends seem to have disappeared, 



D.c. T 



