ABSTRACT
In some wild herbivores, seasonally varying set points may be the dominant factor. The vast bulk of information about intake regulation is for domestic herbivores. There have been many reviews of animal factors affecting intake regulation in herbivores, but the most comprehensive have been by Weston, R. H., and these are drawn on extensively here. It is generally considered that the accumulation of digesta solids in the rumen imposes an important limitation on forage intake, and thus the rate of removal of digesta from the rumen is important in intake regulation. If forage contains elements toxic to either the animal or its microbiota, food intake is depressed. Often substances that are secondary plant metabolites cause toxic effects. The regulation of forage intake by free-ranging wild herbivores is through both internal controls concerned with digestion, rate of passage of digesta through the digestive system, and set points probably including energy balance and body composition.
