A novel method to determine simultaneously methane production during in vitro gas production using fully automated equipment

Abstract

a b s t r a c tAn adaptation of fully automated gas production equipment was tested for its ability to simultaneously measure methane and total gas. The simultaneous measurement of gas production and gas composition was not possible using fully automated equipment, as the bottles should be kept closed during the incubations. A separate small opening with a screw cap and septum was made in each bottle, making it possible to take very small aliquots (10 l) from the gas in the headspace with a syringe for immediate gas analysis. As the used automatic gas production equipment was a venting system, corrections had to be made for the vented total gas and methane, as well as for the dilution of the produced methane with the gas in the headspace. To test the suitability and accuracy of the system, known amounts of methane were injected in bottles in the venting system and methane concentrations in the headspace were determined. It proved that the methane concentration in the headspace, corrected for the vented gas, coincided with the injected amount of methane. To show the potency of the adapted equipment, experiments were conducted with different feedstuffs. Total gas production and methane production were recorded and their relationships were calculated. The ability of the system to test feed additives for methane reduction was demonstrated for maize and soybean hulls as substrate (0.5 g DM), supplemented with monensin (15 mg), sodium-2-bromoethanesulphonate (BES, 15 mg), cinnemaldehyde (150 mg) and tea tannins (150 mg), additives known to effect methane synthesis. The adapted gas production equipment showed to be a powerful tool to determine rate and extent of gas production as a measure of fermentation and to simultaneously determine methane production.

Diet supplementation with cinnamon oil, cinnamaldehyde, or monensin does not reduce enteric methane production of dairy cows

“…This reduction occurred with a concomitant decrease in total VFA production, an indication of an inhibition of feed digestion. In a previous in vitro study by Pellikaan et al (2011), CH 4 production was almost completely inhibited (~100% reduction) during the first 30 h of 72 h incubation when CDH (2.5 mg/ml) was added to soybean hulls or corn. Interesting, in the study of Pellikaan et al (2011), the extent of decrease of CH 4 production from soybean hulls was only 65% after 72 h incubation, suggesting a possible adaptation of rumen microbes to CDH exposure.…”

“…In a previous in vitro study by Pellikaan et al (2011), CH 4 production was almost completely inhibited (~100% reduction) during the first 30 h of 72 h incubation when CDH (2.5 mg/ml) was added to soybean hulls or corn. Interesting, in the study of Pellikaan et al (2011), the extent of decrease of CH 4 production from soybean hulls was only 65% after 72 h incubation, suggesting a possible adaptation of rumen microbes to CDH exposure. Adaptation of rumen microbes to essential oils was previously reported in continuous-culture studies (Cardozo et al, 2004;Busquet et al, 2005).…”

Design, implementation and interpretation of in vitro batch culture experiments to assess enteric methane mitigation in ruminants—a review

“…In certain instances a substrate by additive interaction has been observed. Pellikaan et al (2011) reported a complete inhibition of CH 4 production during the first 30 h of incubation, irrespective of substrate composition (soyhulls or maize), with bromoethanesulphonate (BES) and cinnamaldehyde. However, CH 4 production from soybean hulls with BES or cinnamaldehyde was 65% lower compared with soyhulls without additive after 72 h, suggesting an influence on adaptation, whereas no CH 4 was produced after 72 h production when maize was incubated with these additives.…”

“…Machmüller et al (2001) investigated effects of medium chain fatty acids in incubations containing high or low amounts of fiber. The efficacy of monensin has been examined using corn meal or timothy hay (Russell and Strobel, 1988) and corn meal or soyabean hulls (Pellikaan et al, 2011) as substrates. In certain instances a substrate by additive interaction has been observed.…”

“…Even in automated systems, analysis of gas composition (e.g. CH 4 ) typically requires manual injection of sample gases into a gas analyzer (Martínez et al, 2010;Pellikaan et al, 2011). Cornou et al (2013) described the results of a ring-test evaluating the use of a wireless system for automated gas release developed by Ankom (Ankom Technology, Macedon, NY, USA).…”