Study on single calibration of near infrared reflectance spectroscopy for lignin

Abstract

The study of single calibration of near infrared reflectance srectroscory for lignin was done using 50 feed samples and its paired 50 fecal samrles from dairy cows. These samrles were collected from digestion trials. in which the in vivo digestibility values were deternlined, The dlgC-ostibillty of these feed samples were separated into two grours, namely Italian ryegruss only (n= 19) and combinution of Italian ryegrass and concentmte (n=31), The NIRS srectm or these samrles were recorded using I'aciflc Scientific (Neotec) model 6500 (Perstorp Analytical, Silver Srring, MD) instrument equirrl'Cl with lSI software (InfraSoft International, Port Matilda, PAl for analysIs, Three arproach methods for devcloring the single calibmtion were, (I) Lignin in feed and feces was detcn;1ined usmg lignin calibratIOn developed from Italian ryegrass (L1RG): (2) Lignin of ft.'Cd and feces was detennined lIsing lignin calibmtion developed ITom feces (LFEC): and (3) Lignin oC feed and feces were detemlined using the caiibmtion equation for lignin develorcd from Si.U11rles of fecdstufl's wld feces (LMIX). The resulb showed that lignin of feed and feces in il~ function for digestibility marker could be detennincd by single calibration developed from samrles consisting of Italian ryegm~s, concentrates and feces.