University of California

Internal parasites prevalent in California's beef cattle


Daniel J. Drake
Edward R. Atwill
Ralph Phillips
Eileen Johnson

Authors Affiliations

D.J. Drake is UC Cooperative Extension Advisor, Siskiyou County; E.R. Atwill is Veterinary Epidemiologist, School of Veterinary Medicine, and Cooperative Extension Specialist, Veterinary Medicine Teaching and Research Center, Tulare; R. Phillips is UCCE Advisor, Kern County; E. Johnson is Veterinary Parasitologist, Veterinary Medical Teaching Hospital, UC Davis.

Publication Information

Hilgardia 55(2):28-32. DOI:10.3733/ca.v055n02p28. March 2001.

PDF of full article, Cite this article


Sixty percent of cattle not dewormed within 4 months of sampling were shedding parasite eggs or larva. The prevalence of shedding varied greatly for different types of internal parasites. Prevalence of shedding for major Strongylate nematodes was 54%; thread-necked intestinal nematodes, 6%; lungworms, 0.8%; coccidia, 18.1%; and tapeworms, 2.1%. Anthelmintic (deworming) treatments lowered prevalence compared to untreated cattle, but the major Strongylate nematodes and coccidia were still sufficiently prevalent that the resulting pasture contamination would restrict the potential success of control programs.

Further reading

Albaugh R, Bushnell RB, Loomis EC. Factors affecting the cattle producer's income. UC Division of Agricultural Sciences, Leaflet 2313 1980. p.18.

Corwin RM, Nahm J. Veterinary Parasitology. University of Misssouri-Columbia. 1997. College of Veterinary Medicine www.parasitology.org

Corwin RM, Randle RF. Common Internal Parasites of Cattle. 1993. Department of Veterinary Microbiology, College of Veterinary Medicine, University of Missouri-Columbia Agricultural publication G02130. http://muextension.missouri.edu/xplor/agguides/ansci/g02130.htm

Ensminger ME, Oldfield JE, Heinemann WW. Feeds and Nutrition. 2nd ed. 1990. Clovis, CA: Ensminger Publishing Co. 505p.

Johnstone C. Parasitology 4001, Internal Parasites of Cattle. 1996. University of Pennsylvania School of Veterinary Medicine, http://cal.vet.upenn.edu/parasit/cattle/indexcattle.html

Strickland JE. Internal parasite control in cattle. 1992. University of Georgia College of Agricultural & Environmental Sciences in Siskiyou County, Cooperative Extension Service, Bulletin 1086. www.ces.uga.edu/pubs/b1086-w.html .

Drake D, Atwill E, Phillips R, Johnson E. 2001. Internal parasites prevalent in California's beef cattle. Hilgardia 55(2):28-32. DOI:10.3733/ca.v055n02p28
Webmaster Email: sjosterman@ucanr.edu