title: Predicting feed digestibility from NIRS analysis of pig faeces.
abstract: Digestibility is a key parameter in the evaluation of feeds; however, the measurements on animals require heavy experimental trials, which are hardly feasible when large numbers of determinations are required - for example, in genetic studies. This experiment aimed at investigating the possibility to predict digestibility from NIRS spectra measured on faeces. A total of 196 samples were available from a digestibility experiment investigating the effects of age and genetic background of Large White pigs fed the same diet, rich in fibre (NDF=21.4% DM). Digestibility of dry matter (dDM), organic matter (dOM), nitrogen content (dN), energy (dE) and apparent digestible energy content (ADE) were calculated, as well as total N content of faeces (N). The faeces samples were submitted to reflectance NIRS analysis after freeze-drying and grinding. Calibration errors and validation errors were, respectively, 0.08 and 0.13% DM for total N in faeces, 0.97% and 1.08% for dDM, 0.79% and 1.04% for dOM, 1.04% and 1.47% for dN, 0.87% and 1.12% for dE and 167 and 213 kJ/kg DM for ADE. These results indicate that NIRS can account for digestibility differences due to animal factors, with an acceptable accuracy. NIRS appears to be a promising tool for large-scale evaluations of digestibility. It could also be used for the study of digestibility of different feeds, after appropriate calibration based on a wide range of feed types.
authors.affiliation: 1CIRAD,UMR SELMET,Baillarguet TA C-112/A,F-34398 Montpellier Cedex 05,France.
authors.forename: D
authors.initials: D
authors.lastname: Bastianelli
authors.affiliation: 1CIRAD,UMR SELMET,Baillarguet TA C-112/A,F-34398 Montpellier Cedex 05,France.
authors.forename: L
authors.initials: L
authors.lastname: Bonnal
authors.affiliation: 2INRA,UMR1348 PEGASE,F-35590 Saint-Gilles,France.
authors.forename: Y
authors.initials: Y
authors.lastname: Jaguelin-Peyraud
authors.affiliation: 2INRA,UMR1348 PEGASE,F-35590 Saint-Gilles,France.
authors.forename: J
authors.initials: J
authors.lastname: Noblet
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004032:Diet / Q000662:veterinary*; D004043:Dietary Fiber / Q000032:analysis*; D004063:Digestion; D002149:Energy Intake; D005243:Feces / Q000737:chemistry*; D009584:Nitrogen; D013552:Swine / Q000502:physiology*
chemical_list: D004043:Dietary Fiber; D009584:Nitrogen
keywords: NIR spectroscopy