Skip to main content Accessibility help

Modelling fermentation in an in vitro gas production system: effects of microbial activity

  • N. S. Jessop (a1) and M. Herrero (a1)


In order to understand and ultimately predict the voluntary intake and performance of ruminants, it is necessary to know the nutritional value of foods. Most recent systems for predicting nutrient supply are dynamic in nature and characterize foods in terms of the quantities of available nutrients and their potential rates of supply. The in vitro gas production system has been used to characterize the carbohydrate fraction of foods in this manner. For the technique to be able to do this, two assumptions must be satisfied. First, that the rate of fermentation is limited by characteristics of the food and secondly that the pattern of gas production correlates closely with the pattern of food fermentation.Low microbial activity within the system could invalidate both assumptions since it could (i) limit the rate of food fermentation, thus not allowing the potential rate determined by the physical and chemical nature of the food to be measured and (ii) result in partition of food carbohydrate into new microbial matter, thus reducing the amount of volatile fatty acids and hence gas produced per unit of food fermented.

The aims of this study were mathematically to simulate food fermentation within an in vitro system and to use this representation to investigate the potential effects of variation in microbial activity on the characterization of foods.



Hide All
Baldwin, R. L., Lucas, H. L. and Cabrera, R. 1970. Energetic relationships in the formation of fermentation end-products. In Physiology of digestion and metabolism in the ruminant (ed. Phillipson, A. T.), pp. 319334.Oriel Press, Newcastle upon Tyne.
Beuvink, J. M. W. and Spoelstra, S. F. 1992.Interactions between substrate, fermentation end-products, buffering systems and gas production upon fermentation of different carbohydrates by mixed rumen microorganismsin vitro. Applied Microbiology and Biotechnology 37:505509.
Blümmel, M., Steingass, H. and Becker, K. 1997. The relationship between in vitrogas production, in vitromicrobial biomass yield and 15N incorporation and its implications for the prediction of voluntary feed intake of roughages. British Journal of Nutrition 77: 911921.
Czerkawski, J. W. 1986. An introduction to rumen studies. Pergamon Press, Oxford.
Gordon, I. J. and Illius, A. W., 1996. The nutritional ecology of African ruminants: a reinterpretation. Journal of Animal Ecology 65: 1828.
Herrero, M. and Jessop, N. S. 1997. Broad-based calibrations of in vitrogas production of forages by near-infrared reflectance spectroscopy. In In vitro techniques for measuring nutrient supply to ruminants(ed. Deaville, E. R., Owen, E., A. T., Adesogan, Rymer, C., Huntington, J. A. and Lawrence, T. L. J.), pp. 234237. British Society of Animal Science occasional publication no. 22.
Herrero, M. and Jessop, N. S. 1996. Relationship between in vitrogas production and neutral-detergent fibre disappearance in three tropical grasses. Animal Science 62: 882 (abstr.).
Leatherbarrow, R. J. 1992. GraFit version 3, Erithacus Software Ltd, Staines, UK.
Jessop, N. S. and Herrero, M. 1996. Influence of soluble components on parameter estimation using the in vitrogas production technique. Animal Science 62: 626627 (abstr.).
Menke, K. H. and Steingass, H. 1988. Estimation of the energetic feed value obtained from chemical analysis and in vitro gas production using rumen fluid. Animal Research and Development 28: 755.
Russell, J. B., O'Connor, J. D., Fox, D. G., Van Soest, P. J. and Sniffen, C. J. 1992. A net carbohydrate and protein system for evaluating cattle diets: I. Ruminal fermentation. Journal of Animal Science 70: 35513561.
Theodorou, M. K., Williams, B. A., Dhanoa, M. S., McAllan, A. B. and France, J. 1994. A simple gas production method using a pressure transducer to determine the fermentation kinetics of ruminant feeds. Animal Feed Science and Technology 48: 185197.

Modelling fermentation in an in vitro gas production system: effects of microbial activity

  • N. S. Jessop (a1) and M. Herrero (a1)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed