G. LICITRA a, T.M. Hernandez b, P.J. Van Soest b,*
a- Università di Catania I.S.T.P.A-Progetto IBLEO, Via Val di Savoia 5, 95123 Catania, Italy
b- Cornell University, 324 Morrison Hall, Ithaca, NY 14853 USA
ABSTRACT
The Cornell Net Carbohidrate Protein Model (Chalupa et. al., 1991; Sniffen et al., 1992) has developed the need for uniform procedures to partition feed nitrogen into A, B, and C fractions (Pichard and Van Soest, 1997). While carbohydrate fractios are relatively standardized (based on NDF, ADF with corrections for ash, protein, and lignin), the fractionation of plant nitrogen has been open to dconsiderable variation in procedure. This has led to non-uniformity among reported values for nitrogen fractions. This paper recommends reliable procedures for nonprotein nitrogen (NP) and buffer-soluble protein. These procedures have been examined for reproducibility and relevance to biological expectations. Procedures for acid-detergent insoluble nitrofen (ADIN), and neutral-detergent insoluble nitrogen (NDIN) are also included as they are required for the model. Some alternatives in certain procedures are offered.
Giuseppe Licitra
Prof. DISPA Università di Agraria Catania
caccamo@corfilac.it
