estimation of metabolizable energy of eillam range plants using in vitro tilley and terry method and mathematical models

the aim of this study was to produce some of data needed for completing the iranian feed composition tables. the analyzed data in this research was from eilam range plants. the information about the range plants was collected from laboratory of animal science research institute of iran and some data was obtained from the final reports of research projects. the metabolized energy of range plants were prepared using in vitro tilley and terry method and some of data were estimated using mathematical models including: linear, logarithmic, inverse, quadratic, cubic, power, s, and exponential fitted equations from digestible organic matter in dry matter (domd). for this purpose domd was used as independent value. among different equations, the simplest one with highest r2 was me (mcal/dm) = -2.160 e-15 + 0.0037 (domd g/kg). estimated me for eillam range plants was 2.01 mcal/kg based on tilley and terry method and the estimated digestible energy (de) was 2.46 mcal/kg dm. net energy for maintenance (nem) and net energy for gain (neg) were 1.16 and 0.60 mcal/kg dm receptively.