A Robust Quality Assurance, Troubleshooting, and Reporting Protocol for Near-Infrared Reflectance Spectroscopic Forage Testing.

Forage quality is valuable and practical considerations for animal nutritionists and livestock entrepreneurs; and forage producers, hay brokers and others using forage quality to set the selling price. Near-Infrared-Reflectance-Spectroscopy (NIRS) provides an accurate, less expensive alternative to “wet chemistry” for forage analysis, while reducing time and eliminating hazardous chemicals.  However, its success depends on: 1) applying proper calibration; 2) proofing- verification-troubleshooting of the predictions; 3) proper calculation of total digestible nutrients (TDN) and relative forage quality (RFQ); 3) proper production of reports. We developed and implemented a comprehensive protocol for sample processing, testing, quality assurance, and reporting various types of forage analyses by NIRS that ensures: 1) appropriate calibrations are applied; 2) the predicted values are proofed – verified with the established acceptance limits; 3) values falling outside the limits are verified by wet chemistry; 3) TDN, other energy values, and RFQ are properly calculated; 4) quality control standards are analyzed before testing routine samples to ensure equipment and technicians are operating correctly; 5) weekly quality assurance reports are created and distributed among the experts for verification and troubleshooting; 6) substantial expansion of the forage quality metrics on the reports, thereby increasing their values. This protocol led our NIRS forage analysis program to a substantially improved level for producing authentic, useful, and defensible results, which has had several positive impacts.  We believe this has reduced our error rate down to less than 1%.  Without this protocol, human error could produce incorrect results, which could cause underestimation or overestimation of forage quality in some cases and consequently a lower or higher market value for the product for the forage marketer or could have caused the livestock producer to purchase and use incorrect amount of supplemental energy sources than need be. In some instances this could cause the producer/user suffer significant economic loss.