@article{MAKHILLJAVA201110182989, title = {Comparison of Some Mathematical Models Used in Gas Production Technique}, journal = {Journal of Animal and Veterinary Advances}, volume = {10}, number = {18}, pages = {2465-2469}, year = {2011}, issn = {1680-5593}, doi = {javaa.2011.2465.2469}, url = {https://makhillpublications.co/view-article.php?issn=1680-5593&doi=javaa.2011.2465.2469}, author = {Adile,A. Ihsan,C. Ozgur,Inan and}, keywords = {mathematical model,wheat straw,vetch hay,wheat grain,In vitro fermentation,gas production kinetics}, abstract = {The aim of this study was to compare some mathematical models used in vitro gas production technique. Chemical composition including Dry Matter (DM), Crude Protein (CP), Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF) and ash contents of feedstuffs were determined. Gas productions were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h incubation times and their kinetics were estimated using the four different mathematical models. The mean square error of wheat grain, vetch hay and wheat straw ranged from 5.589-10.538, 1.590-9.668 and 0.814-12.118, respectively. The adjusted coefficient of determination of wheat grain, vetch hay and wheat straw ranged from 0.979-0.989, 0.962-0.992 and 0.976-0.995, respectively. The Durbin-Watson statistic of wheat grain, vetch hay and wheat straw ranged from 1.378-2.479, 1.502-2.928 and 1.178-3.623, respectively. The best model for the gas production of wheat grain was the Von Bertalanfyy and France functions when MSE and R2adj parameter was taken into consideration. The best model for the gas production of vetch is the Von Bertalanfyy function when MSE parameter was taken into consideration whereas the best model for vetch hay was the Von Bertalanfyy and Orskov functions when R2adj parameter was taken into consideration. The best model for the gas production of wheat straw is the Orskov, Menke and Von Bertalanfyy functions when MSE parameter was taken into consideration whereas the best model for the wheat straw was the Von Bertalanffy function when the R2adj parameter was taken into consideration. The best model for the gas production of wheat grain is the Orskov and Von Bertalanfyy functions when DW parameter was taken into consideration. On the other hand, the best model for the gas production of vetch hay and wheat straw is the Orskov and Menke functions when DW parameter was taken into consideration. There is no 1st order autocorrelation in errors of wheat grain and vetch hay estimated by four models used in the current study therefore, the four models can be used to fit the individual gas production data measured in different time intervals. Von Bertalanffy function is not suggested to fit the gas production data since, there is negative autocorrelation in errors of wheat straw. As a conclusion, choice of best model should be made on the basis of fitting criteria and feedstuffs since, goodness of fit of model is depended on feedstuffs tested and fitting criteria.} }