Location: Poisonous Plant Research
Title: Mitigation of larkspur poisoning on rangelands through the selection of cattle Authors
Submitted to: Rangelands
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 31, 2013
Publication Date: February 1, 2014
Citation: Green, B.T., Welch, K.D., Pfister, J.A., Chitko McKown, C.G., Gardner, D.R., Panter, K.E. 2014. Mitigation of larkspur poisoning on rangelands through the selection of cattle. Rangelands. 36(1): 10-5. Interpretive Summary: Larkspurs (Delphinium species) are poisonous plants that negatively impact the earning potential of beef producers in many western rangelands of North America. If ranchers are unfortunate enough to have large stands of toxic larkspur (both tall and low larkspurs) in their pastures, yearly herd mortality can be as high as 10%. Across the western United States, this results in annual economic losses of millions of dollars in animal deaths, increased management and treatment costs, and if animals are deferred from grazing, the underutilization of otherwise highly nutritious pastures and rangelands. The quality of the ranges where larkspur grows cannot be overemphasized. Stocker cattle grazing on larkspur rangeland can gain upwards of 2.5 pounds per day or more. Furthermore, at the first signs of poisoning many producers move cattle off this high quality rangeland and leave valuable forage unused. The purpose of this report is to provide a brief review of basic information about larkspur and larkspur poisoning in cattle, and to describe recent research evidence that cattle can be selected for resistance to larkspur poisoning.
Technical Abstract: Toxic larkspur (Delphinium species) in the western United States cause large economic losses from cattle deaths, increased management costs, and reduced utilization of pastures and rangelands. Peak larkspur toxicity coincides with maximum productivity of the range, which reduces the profitability of larkspur-containing rangelands. Selection of cattle resistant to larkspur poisoning has the potential to reduce cattle losses and improve rangeland utilization. Additionally, the use of genetic-based herd management decisions provides another tool for livestock producers to improve their profit margin and enhance the economic sustainability of rural American communities. ARS researchers can determine the alkaloid profile and obtain a risk assessment for larkspur species on your range before turning out. Furthermore, plants may be submitted to the USDA-ARS Poisonous Plant Research Laboratory for chemical evaluation and follow-up risk assessment at no charge. Information is available at http://www.ars.usda.gov/main/site_main.htm?modecode=54-28-20-00 or by telephone: 435-752-2941, Ext. 0