The use of R Programming Language for modelling in vitro Rumen fermentation gas production H. Herdian a), A. Sofyan a), H. Kusnadi a), A.S. Anggraeni b), I. N. G. Darma c)
a) Research Center for Animal Husbandry National Research and Innovation Agency (BRIN), Cibinong Indonesia
b) Research Center for Food Technology and Processing National Research and Innovation Agency (BRIN), Gunungkidul Indonesia
c) IPB University Bogor Indonesia
Abstract
For feed evaluation involving the microbial fermentation process in the rumen by the in vitro technique, a program script has been made using the R programming language to carry out the fitting data process of gas production observation from rumen fluid fermentation. The calculation process uses nonlinear mathematical equations from Orskov and McDonald (1979). The equation shows the gas production (P) (mL) is influenced by several constants that indicate the share of gas production from the soluble fraction (FA) (mL), gas production from the potentially soluble part (FB) (mL/h), gas production rate (KC) (mL/h) and incubation time (T) (h), in addition to P and T, the three constants are tried to be derived by the program created. The data set was taken from the study of (Sofyan, et al 2023) and (Anggraeni, et al, 2022). The Neway Software program of curve fitting calculations from Chen (1997) was used to validate the results, as the mean difference was tested using an unpaired T-test. Both programs showed the same calculation results for FA (P=0.9996), FB (P=0.9998), and KC (P=0.9962). The residual standard error (RSE) and R-square (R2) values of both programs also came with the same result they were RSE (P =0.9978 ), and R2 (P=0.6087) respectively. This shows that the R program script made can carry out the calculation process of making a model of the gas production equation for modeling in vitro gas production from rumen fermentation.
Keywords: In vitro, rumen gas production, R language program
