ARS | Publication request: Fluorometry As a Tool for Determining Botanical Composition

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: February 1, 2001
Publication Date: February 1, 2001
Citation: ANDERSON, D.M., RAYSON, G., ESTELL, R.E., FREDRICKSON, E.L., HAVSTAD, K.M., TISONE, G., DANIEL, D., MURRAY, L.W. FLUOROMETRY AS A TOOL FOR DETERMINING BOTANICAL COMPOSITION. 54TH ANNUAL MEETING, SOCIETY FOR RANGE MANAGEMENT. 2001. ABSTRACT NO. 10.

Technical Abstract: Multidimensional fluorometry measurements offer a unique chemical approach for determining botanical composition of animal diets. By focusing on electronic transitions between 190 and 800 nm specific chemical structures within materials such as fecal matter and dietary extrusa can be determined in real time using simple "trainable" algorithms. In November 1991, we began investigating fluorometry as a tool to evaluate pre- and post-digested diets of free-ranging animals. During the ensuing nine years, a laser as well as some xenon arc lamps have been used to excite fluorescence from plant and fecal extracts in polar as well as non-polar solvents. Unique spectral signatures in the blue, green and red regions of the visible spectrum were obtained. Research to date has concentrated on the acquisition and post-processing of excitation/emission matrices. Results suggest the technique has the ability to discriminate differences among pre-digested grasses, forbs and shrubs as well as reveal similarities among different plants within a species. In addition, simple diets containing varying amounts of one of the components can be statistically separated using distinct peaks as well as the entire fluorescence data set. Current and future research using fluorometry will be discussed.