196 



TlIF TELOSPORASIDA AND THE COCCIDIA PROPER 



EIMERIA FELINA 

 NIESCHULZ, 1924 



Hosts : Cat, lion. 



Location : Unknown. Oocysts found 

 in feces. 



Geographic Distribution : Europe 

 (Holland). 



Prevalence : Rare. 



Morphology : The oocysts are ellip- 

 soidal, 21 to 26 by 13 to 17 ji with a mean 

 of 24 by 14. 5ji. The oocyst wall is about 

 1 ^t thick, smooth, colorless, and double 

 contoured. A definite micropyle is ab- 

 sent. An oocyst polar granule is absent. 

 An oocyst residuum is present. The 

 sporocysts are elongate ovoid, with a 

 Stieda body. A sporocyst residuum is 

 present. The sporozoites are comma- 

 shaped, with a large vacuole at the large 

 end and usually a small one at the small 

 end. 



Life Cycle : Unknown. 



Pathogenesis: Unknown. 



EIMERIA STIEDAE 



(LINDEMANN. 1865) 



KISSKALT AND HARTMANN, 1907 



Synonyms : Monocystis stiedae, 

 Cocciditu)! ovi/orme, Coccidium cimicidi. 



Hosts : Domestic rabbit, European 

 hare (Lepus europaeiis), varying hare 

 (L. aniericanHs), black-tailed jack rabbit 

 (L. calif or nic us), alpine hare (L. tini- 

 idus), L. variabilis, cottontails {Sylvil- 

 agus floridanus , S. nuttalli). 



Location : Liver. The coccidia are 

 found in the bile duct epithelial cells. 



Geographic Distribution : Worldwide. 



Prevalence : This is the most com- 

 mon and most important coccidium of 

 domestic rabbits. It also occurs in hares 

 {Lepus), but is less common in cottontails 

 than other species. 



Morphology : The oocysts are ovoid, 

 sometimes ellipsoidal, with a flat micro- 

 pylar end, and measure 28 to 40 by 16 to 

 25 ji with a mean of 37 by 21 /i . The 

 oocyst wall is smooth and salmon-colored. 

 A micropyle is present. An oocyst polar 

 granule and oocyst residuum are absent. 

 The sporocysts are elongate ovoid, 18 to 

 10 |i, with a Stieda body. A sporocyst 

 residuum is present. The sporulation 

 time is 3 days. 



Life Cycle : The life cycle of this 

 species has been studied by a number of 

 workers (see Becker, 1934, for a review). 

 The sporulated oocysts excyst in the small 

 intestine. The sporozoites penetrate the 

 intestinal mucosa, enter the hepatic portal 

 system, and pass to the liver. Here they 

 enter the epithelial cells of the bile ducts. 

 The liver parenchyma cells are only rarely 

 invaded. Development takes place above 

 the host cell nucleus. Each sporozoite 

 rounds up and becomes a schizont which 

 produces 6 to 30 or more (usually 8 to 16) 

 merozoites which measure about 8 to 10 

 by 1. 5 to 2. 0(1 . The number of asexual 

 generations is not known. Later, some 

 merozoites become microgametocytes 

 which produce large numbers of comma- 

 shaped, biflagellate microgametes, while 

 others become macrogametes. These are 

 fertilized, lay down an oocyst wall, break 

 out of their host cell, pass into the intes- 

 tine with the bile and thence out of the 

 body. The prepatent period is 18 days. 



Pathogenesis : In mild cases of liver 

 coccidiosis there may be no signs, but in 

 more severe ones the animals lose their 

 appetites and grow thin. There may be 

 diarrhea, and the mucous membranes may 

 be icteric. The disease is more severe in 

 young animals than in old. It may be 

 chronic, or death may occur in 21 to 30 

 days. 



Some of the symptoms are due to in- 

 terference with liver function. The liver 

 may become markedly enlarged, and white 

 circular nodules or elongated cords appear 

 in it. At first they are sharply circum- 

 scribed, but later they tend to coalesce. 

 They are enormously enlarged bile ducts 

 filled with the developing parasites. 

 There is tremendous hyperplasia of the 



