Adile  Tatliyer, A. Ihsan  Atalay, C. Ozgur  Ozkan, Inan  Guven, Mustafa  Sahin, 
    Comparison of Some Mathematical Models Used in Gas Production Technique,
    Journal of Animal and Veterinary Advances,
    Volume 10,Issue 18,
    2011,
    Pages 2465-2469,
    ISSN 1680-5593,
    javaa.2011.2465.2469,
    (https://makhillpublications.co/view-article.php?doi=javaa.2011.2465.2469)
    Abstract: The aim of this study was to compare some mathematical models 
  used <I>in vitro</I> 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 R<SUP>2</SUP><SUB>adj</SUB> 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 R<SUP>2</SUP><SUB>adj</SUB> 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 
  R<SUP>2</SUP><SUB>adj</SUB> 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.
    Keywords: mathematical model;wheat straw;vetch hay;wheat grain;In vitro fermentation;gas production kinetics