Hostname: page-component-8448b6f56d-c4f8m Total loading time: 0 Render date: 2024-04-25T00:46:07.369Z Has data issue: false hasContentIssue false
  • English
  • Français

Factors affecting the amount of indirect gas produced by the in vitro gas production technique

Published online by Cambridge University Press:  27 February 2018

C. Rymer ,
A. R. Moss ,
E. R. Deaville  and
D. I. Givens
C. Rymer
Affiliation:
ADAS Feed Evaluation and Nutritional Sciences, Alcester Road, Stratford-upon-Avon CV37 9RQ
A. R. Moss
Affiliation:
ADAS Feed Evaluation and Nutritional Sciences, Alcester Road, Stratford-upon-Avon CV37 9RQ
E. R. Deaville
Affiliation:
ADAS Feed Evaluation and Nutritional Sciences, Alcester Road, Stratford-upon-Avon CV37 9RQ
D. I. Givens
Affiliation:
ADAS Feed Evaluation and Nutritional Sciences, Alcester Road, Stratford-upon-Avon CV37 9RQ
Get access

Extract

When a food is ingested by a ruminant animal, the carbohydrate fraction of the food is fermented by the rumen micro-organisms to produce gas (predominantly carbon dioxide and methane) as well as volatile fatty acids (VFA). The gas production technique simulates this fermentation process and provides an estimate of both the rate and extent of fermentation. Comparing the gas production (GP) profiles of foods enables a comparison to be made of the fermentative characteristics of different foods. However, the technique uses a bicarbonate-based medium system with the rumen liquor. This complicates the GP profile because of the production of ‘indirect’ gas resulting from the reaction between the VFA and the bicarbonate ions.

Beuvink and Spoelstra (1992) measured the volume of gas produced from buffered rumen fluid when known amounts of VFA were added and observed that 20·8 ml gas were released per mmol VFA. However, there is variation between laboratories in terms of the composition of the medium that is used. Even when the same medium is used, significant differences have been observed in the GP profile when different types of apparatus were employed (Rymer and Givens, 1997). Media are gassed with carbon dioxide before they are added to the gas production system and it is possible that the concentration of carbon dioxide dissolved in the medium varies between experiments. The objective of this experiment, therefore, was to determine whether the volume of indirect gas produced was affected by the composition of the medium, the addition of carbon dioxide, and the technique employed to measure gas production.

Type
In vitro techniques for measuring rumen microbial activity
Information
BSAP Occasional Publication , Volume 22: In vitro techniques for measuring nutrient supply to ruminants , 1998 , pp. 89 - 91
Copyright
Copyright © British Society of Animal Science 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Beuvink, J. and Spoelstra, S. 1992. Interactions between substrate, fermentation end-products, buffering systems and gas production upon fermentation of different carbohydrates by mixed rumen micro-organisms in vitro . Applied Microbiology and Biotechnology 37: 505–509.CrossRefGoogle Scholar
Cone, J. W., Gelder, A. H. van, , Visscher, G. J. W., and Oudshoorn, L. 1996. Influence of rumen fluid and substrate concentration on fermentation kinetics measured with a fully automated time related gas production apparatus. Animal Feed Science and Technology 61: 113–128.CrossRefGoogle Scholar
Rymer, C. and Givens, D. I. 1997. A comparison of different types of apparatus used for measuring gas production in vitro . Proceedings of the British Society of Animal Science 1997 p.193.CrossRefGoogle Scholar
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: 185–197.CrossRefGoogle Scholar