Composition of the rumen ciliate population in experimental herds of cattle and sheep in Lethbridge, Alberta, Western Canada.

Rumen ciliate populations were surveyed in 11 Holstein cattle and 6 sheep in Lethbridge (Alta., Canada) to determine species distribution in this Western Canadian environment. A total of 28 ciliate species were identified in cattle and 17 in sheep. The average total number of ciliates per millilitre of rumen content was 6.9 X 10(4) in cattle and 1.9 X 10(5) in sheep. The average number of species per host was 20.5 in cattle and 13.8 in sheep. Of the ciliate species detected, species of Entodinium appeared most frequently both in cattle and in sheep. Diplodinium polygonale, Eodinium lobatum, Eo. monolobum, Eremoplastron rostratum, Ostracodinium clipeolum, Os. mammosum, and Ophryoscolex purkynjei were not detected in sheep. In contrast, Ophryoscolex caudatus was not found in cattle. These data indicate that the ciliate faunas of cattle and sheep in this Western Canadian environment are similar to those found in Japan.