Certain plants, like some weeds and ornamentals are toxic, and during times of dry conditions when no other pasture feed is available, livestock may be inclined to consume them, says Steve Boyles, Ohio State University (OSU) Extension beef specialist.
Toxic weeds are typically in the pastures all the time and livestock normally leave them alone. The concern is that such plants may be the only thing green still standing during drought situations, making them more desirable to grazing animals.
Producers should get to know the more common toxic weeds and plants and keep livestock well fed to ensure they aren't tempted to eat them, Boyles says.
One concern may be the risk of cyanide poisoning. Symptoms include labored breathing, staggering, trembling muscles, convulsions and death. In Ohio, some sources of cyanide poisoning include twigs and leaves of wild and cultivated cherry trees and certain marsh grasses, such as arrowgrass. The grass contains a high salt content and lack of salt on the pasture may drive livestock to feed on the plant to meet salt requirements.
Producers can minimize livestock illness from poisonous plants by following the suggested guidelines:
- Learn to ID poisonous plants.
- Supplement feed with salt, minerals and other nutrients.
- Avoid grazing animals in areas of abundant poisonous plants.
- Provide adequate water to prevent non-selective grazing.
- Purdue University -- www.vet.purdue.edu/depts/addl/toxic/cover1.htm.
- "Why Animals Die From Eating Poisonous Plants" fact sheet -- www.behave.net/fact_sheets/PoisonousPlants.pdf.
- Poisonous Plants Section from OSU's Horse Nutrition Bulletin 762-00: ohioline.osu.edu/b762/b762_24.html
- University of Pennsylvania: cal.vet.upenn.edu/poison/
- Cornell University: www.ansci.cornell.edu/plants/index.html.
- www.beefcowcalf.com - type "poisonous plants" into the "Search For" box on the opening page.