Development of Dietary Choice in Livestock on Rangelands and its Implications for Management
Journal of Animal Science
Plant species that constitute forage for a given species of livestock vary tremendously throughout the diverse environments inhabited by domestic livestock. Within neurological, morphological and physiological constraints, learning early in life enables herbivores to develop preferences for or aversions to available plants and to acquire the motor skills necessary to harvest and ingest those forages efficiently. Hence, the foraging experiences of young herbivores undoubtedly affect their dietary habits as adults. Three mechanisms help young herbivores to learn efficiently to select appropriate foods: 1) food imprinting, 2) social models and 3) trial and error. Dietary habits of adults apparently are more stable than those of young herbivores. Adults accept new foods less readily, avoid foods that cause gastrointestinal distress to a greater degree, and are influenced less in choice of diet by social models than young animals are. The ability of livestock to learn dietary habits early in life presents both problems and opportunities for managers. Livestock that forage efficiently in the environment where they are reared may not forage as efficiently in a new environment. Diet training may enable managers to create a foraging group more suited to management goals. Additional research is needed to determine how age at which exposure occurs, as well as how duration, intensity, variability and complexity of exposure early in life affect dietary habits of adults. These variables affect the efficiency of learning and the persistence of dietary habits and thus are crucial to the development of cost-effective management based on diet training.
Provenza, Frederick D.; Balph, David F. 19888. Development of Dietary Choice in Livestock on Rangelands and its Implications for Management. Journal of Animal Science 66(9): 2356-2368.