|Pfister, James - Jim|
Submitted to: Rangelands
Publication Type: Popular Publication
Publication Acceptance Date: 9/1/2000
Publication Date: 4/1/2001
Citation: Ralphs, M.H., Provenza, F.D., Pfister, J.A., Graham, D., Duff, G., Greathouse, G. 2001. Conditioned food aversion: from theory to practice. Rangelands. Interpretive Summary: In most native plant communities there are plants that contain secondary comounds that can poison animals if consumed in sufficient quantities. A few plants contain high levels of toxins, or contain highly toxic compounds, and pose a real threat to grazing livestock. Some of these pants may be relatively palatable, which makes it difficult to manage around them. Conditioned food aversion offers a management tool to train livestock to avoid eating poisonous plants. We have created aversions to tall larkspur, locoweed and ponderosa pine on ranch-scale basis.
Technical Abstract: Conditioned food aversion is a powerful experimental tool to modify animal diets. We have taken it from an experimental tool to a management tool to prevent livestock from grazing poisonous plants like larkspur, locoweed, and ponderosa pine on western U.S. rangelands. The following principles pertain to creating and maintaining aversions on rangeland:; animals are fed the target plant in a pen, then are dosed with an emetic to induce GI distress; lithium chloride (LiCl) is the most effective emetic and the optimum dose for cattle is 200 mg/kg BW and 150 mg/kg BW for sheep; mature animals retain aversions better than young animals; novelty of the plant is important, although aversions can be created to familiar plants; and averted animals should be grazed separately from non-averted animals to avoid the influence of social facilitation which can rapidly extinguish aversions. Cattle that have been averted to tall larkspur and locoweed have abstained from eating these plants in extensive, ranch-scale demonstrations. Aversive conditioning may provide an effective management tool to prevent animals from eating palatable poisonous plants that cause major economic loss.