The ciliated protozoan, Buxtonella sulcata, was found in 28% of a sample of Iowa cattle in 1927, and in 32% of a sample of Louisiana cattle in 1930. As far as we can ascertain it has not been reported in American cattle since. During the summer of 1962, B. sulcata was found associated with ulcerative colitis in a cow from northeast Nebraska. This finding prompted incidence of infection in the region.

Although artificial insemination (A.I.) was initially organized as a means of bringing the service of superior purebred dairy sires to average dairy farms with grade cattle, it has been widely used by breeders of registered purebred cattle. The purpose of this article is to describe the successful use of artificial insemination in a commercial beef cow-calf operation in central South Dakota.