EIMERIA STIEM; 



of the life-cycle) was determined by Fantham to be from eight to ten days, of which 

 period schizogony occupies four to five days. 



The method of infection l is contaminative, by way of food or drink. Young 

 birds are especially susceptible to infection. Certain birds, particularly older ones, 

 may act as reservoirs of oocysts, being continuously infected themselves, without 

 showing any marked ill effects from the parasite, but being highly infectious 

 to other birds. Much moisture retards the development of sporocysts consider- 

 ably. The duration of vitality of the infective oocysts has been determined 

 experimentally to extend well over two years, and in certain cases longer. 

 Eimeria avium is the causal agent of "white diarrhoea" or "white scour" in 

 fowls, and of " blackhead " in turkeys. 



Eimeria avium of birds and E. stiedce of rabbits closely resemble 

 one another, but are not the same parasite, for E. avium is not infective 

 to rabbits, nor E. stiedce to poultry. 



Eimeria stiedae, Linclemann, 1865. 



Syn. : Monocystis stiedce, Lindemann, 1865; Psorospermium cuniculi, Rivolta, 

 1878; Cytospermium hominis, Rivolta, 1878; Coccidium ovifortne, Leuckart, 1879; 

 Coccidium perforans, Leuckart, 1879; Coccidium cuniculi. 



Eimeria stiedce is parasitic in the gut epithelium (fig. 70), liver, and 

 epithelium of the bile ducts of rabbits, and is usually considered to 



FIG. 70. Eimeria stiedce. Section through an infected villus of rabbii's intestine. X 260. 



be the parasite very occasionally found in man. The life-cycle 

 resembles that of Eimeria avium in its general outlines (see fig. 69) 

 and therefore will not be detailed in full here. The oocysts (fig. 71) 

 are large, elongate-oval, greenish in fresh preparations and vary in 

 size from 24 //, to 49 //, long and 12*8 //, to 28 //, broad, the gut forms 

 being usually smaller than those occurring in the liver, owing to the 



1 Fantham, H. B. (1910), " Experimental Studies on Avian Coccidiosis, especially in 

 relation to young Grouse, Fowls and Pigeons," Proc. Zool. Soc. Lond., 1910, pp. 722- 

 731, i plate. 

 10 



