Fecal indices of nutritional status of free-ranging cattle using near infrared reflectance spectroscopy /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1990.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | Research was conducted to test the feasibility of predicting the nutritional status of free-ranging cattle through analysis of fecal material by near infrared reflectance spectroscopy (NIRS). Forage diet samples and fecal samples resulting from consumption of these forage diets were collected. In vivo corrected digestible organic matter (DOM) and percent crude protein (CP), were determined for diet samples. The resulting diet reference data and corresponding fecal spectral data were used to develop predictive equations. In addition, forage intake was estimated. Standard errors of calibration (SEC) and R^2 for DOM, 1.71 and 0.73, and CP, 0.76 and 0.73, equations were deemed satisfactory. However, calibrations for forage intake were judged unsatisfactory due to the high SECs. Experiments were conducted relative to factors affecting rapid sample analysis including time post-grinding and sample hydration status. Post-grinding scanning times of 1 hr and 4 hr had no effect on NIRS analysis. Results from experiments dealing with sample hydration status indicated that reproducible conditions must be established relative to sample hydration to facilitate rapid, precise, and accurate predictions. Experiments with microwave (MW) drying of fecal samples indicated with MW drying can be used for preparation of cattle fecal samples for NIRS analysis. Results from a supplemental feeding study in which cattle were fed a constant daily rate of supplemental feed indicated that this feeding regime did not affect the fecal spectra. Although some DOM and CP predictions in this study were different between treatment groups, differences were not practically significant with regard to feed recommendations. In addition, these results suggested possible sampling strategies to eliminate supplemental feed effects on NIRS predictions. Results from another supplemental feed study in which cattle were fed varying amounts of feed three times per week indicated both spectral differences and practical differences in predictions for treatment groups. However, because of the sampling frequency, this study did not suggest a sampling strategy to avoid supplemental feed interference. Results of these studies indicate that prediction of nutritional status by fecal analysis with NIRS is feasible. Effects of supplemental feeding may be avoided with sampling strategies, however, further studies are required. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Range science." |
| Physical Description: | xiii, 140 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |