Carissa Koopmann Rivers, UCCE Siskiyou County Livestock and Natural Resources Advisor

This blog post was adapted from the UCCE Siskiyou Stockman – Livestock and Rangeland News – April 2016*

UC Davis’s Dr. Jeffery Stott has reached a new milestone is his work to address a major economic loss for California cattle producers—foothill abortion, a tick-borne bacterial disease that is estimated to cause the death of 45,000 to 90,000 calves each year. The first year of field trials is wrapping up, in which Stott’s team successfully vaccinated nearly 10,000 animals in California, Oregon, and Nevada against this deadly disease.


Researchers at the UC Davis School of Veterinary Medicine worked with producers across California’s coastal and foothill regions, Southern Oregon, and Northern Nevada—where foothill abortion is endemic. To be eligible for the trials, producers had to have a minimum of 20 heifers/open cows to vaccinate. The experimental vaccine was administered to open females at least 60 days prior to breeding. Participating producers are asked to donate $800 for every vial (30 doses/vial) of the vaccine, which will support continued production, distribution and record-keeping.


Following 50 years of research by UCCE farm advisors and UC Davis faculty and specialists, the field trials are another major step forward in finding a solution to this deadly disease. The cattle producers participating in these trials have been and will continue to be an integral part in developing a vaccine. At this time, a local pharmaceutical company is working on commercializing the vaccine. However, there has been no announcement of a release date of when the vaccine will be available for commercial purchase. Dr. Stott presumes it is at least one year out.


So far, no formal studies have been conducted to determine if any interference may occur, reducing effectiveness of either the foothill abortion vaccine or other concurrently administered treatments; however, no evidence has emerged suggesting that other vaccines have a negative impact on the efficacy of the foothill abortion vaccine. Additionally, while vaccine efficacy has been confirmed in animals treated at one year of age; the age of females at time of vaccine administration has not been a focus of the trials. However, there’s been no evidence suggesting vaccination of animals as young as 8 months of age compromises efficacy. You can read more details on foothill abortion here, here or watch a presentation from Dr. Stott here.

For information about the vaccination field trials, please contact California Cattlemen’s Association at 916-444-0845.

*Information in this article was provided by Dr. Jeffery Stott, UC Davis.