The Sporulated Oocysts of Eimeria illinoisensis n. sp. and of Other Species of Eimeria of the Ox

Abstract

SYNOPSIS. The sporulated oocysts of 12 species of Eimeria occurring in the ox Bos taurus in the United States are described and differentiated. They are E. alabamensis, E. auburnensis, E. bovis, E. brasiliensis, E. bukidnonensis, E. canadensis, E. cylindrica, E. ellipsoidalis, E. illinoisensis n. sp., E. subspherica, E. wyomingensis and E. zuernii. Two other species, not yet found in North America, which are recognized as valid are E. pellita and E. thianethi. The sporulated oocysts of E. illinoisensis n. sp. are ellipsoidal or slightly ovoid, 24–29 by 19–22 μ with a mean of 26.3 by 20.7 μ; their sporocysts are 13–16 by 6–7 μ with a mean of 15.3 by 6.5 μ. This species was found in 3 cattle from one farm in Illinois.