Nutritional monitoring of rangeland beef cattle in the Edwards Plateau of Texas using region-specific fecal near-infrared spectroscopy predictions of diet quality

•Determining the quality of grazed forage remains a challenge for nutritional modeling and monitoring in livestock.•One method used to accomplish this task has been near-infrared spectroscopy of feces (FNIRS) combined with the Nutritional Balance Analyzer Model (Nutbal).•Users of the FNIRS-Nutbal system in the Edwards Plateau of Texas have observed inaccurate predictions of diet quality on rangelands.•Application of a regional-specific FNIRS calibration improved the estimation of grazing animal diet quality in this region.•Nutritional monitoring of beef cows grazing Edwards Plateau rangeland via the FNIRS-Nutbal system was accurate enough (± 0.5 body condition score, 80% occurrence) to inform management decisions, but incorrect predictions of animal performance did occur.