Determining botanical composition of free-ranging animal diets using physical properties of fecal material

TitleDetermining botanical composition of free-ranging animal diets using physical properties of fecal material
Publication TypeConference Paper
Year of Publication1992
AuthorsAnderson D.M., Havstad K, Estell R.E., Fredrickson E.L., Murray L.W.
Conference NameAnnual Meeting, Society for Range Management
Date Published1992
AbstractTechniques for sampling plants or animals to determine botanical composition of free-ranging livestock diets are tedious and costly. Estimates of diet selection using animal rather than agronomic techniques should provide the most accurate data for management of range livestock. Microhistological analysis of masticate and fecal material has been used extensively to determine diet quality in free-ranging herbivores. However, the major limitation with procedures requiring microscopic analysis is the time required for training, preparation and identification. We propose that physical properties of fecal material, including water adsorption and particle size distribution, may be useful in identifying animals within a species with higher proportions of browse in their diets. Preliminary analyses of dried Angora goat feces collected from animals housed in metabolism stalls indicates feces derived solely from monocots imbibed 63% less water than feces from animals consuming a mixture of monocots and dicots. Data will be presented on additional analyses of other physical properties and more specific dietary components. Determination of inexpensive and rapid yet accurate techniques to separate herbivore diets into grasses, forbs and browse components would be a valuable tool for both scientific and management purposes.