Using strains of Propionibacteria to mitigate methane emissionsin vitro

Abstract

Sixteen strains of propionibacteria were inoculated into in vitro ruminal incubations to evaluate their potential to reduce methane (CH 4 ) production from concentrate and forage diets. Propionibacterium freudenreichii T114, Propionibacterium thoenii T159, and Propionibacterium thoenii ATCC 4874 lowered (p B0.05) CH 4 production from both substrates compared to control. Compared to control, Propionibacterium jensenii T1, Propionibacterium freudenreichii T31, and Propionibacterium freudenreichii T54 lowered (p B0.05) CH 4 production only with corn. Propionibacterium propionicus T83 caused higher (p B0.05) propionate percentage and lower (p B0.05) acetate:propionate than the control with corn; however, this did not result in a decline in CH 4 production. Results demonstrate that some strains of propionibacteria have the potential to lower CH 4 production from mixed ruminal cultures and that this reduction is not always associated with an increase in propionate production.

Enteric methane emissions in response to ruminal inoculation of Propionibacterium strains in beef cattle fed a mixed diet

“…Animals used in the present study had no previous exposure to Propionibacterium strains thereby ruling out the possibility of any carry-over effects that might have confounded results in the present study. The present in vivo study showed no significant treatment effects on total CH 4 production for any of the strains used, in contrast to observations from a previous in vitro study (Alazzeh et al 2013). Moreover, total enteric CH 4 emissions corrected for DM and gross energy intake tended to be greater with the inoculation of Propionibacterium strains.…”

“…However, no effects were observed on total CH 4 emissions due to low persistency of the inoculated strains. Contrary to the previous in vivo studies (Vyas et al 2014a(Vyas et al , 2014b, in vitro batch culture studies with Propionibacterium strains showed promising results with significant reduction in CH 4 production using both high-forage and high-grain diets (Alazzeh et al 2013). The discrepancy between studies might be related to different strains of Propionibacteria used in the in vitro batch culture experiment compared with the in vivo study.…”

“…It is possible that the lack of effect of Propionibacterium species in those studies was due to the strains selected; thus, the present study examined additional Propionibacterium strains. The Propionibacterium strains used in the present study were previously screened for their CH 4 mitigation potential in vitro using both forage-and grain-based diets (Alazzeh et al 2013), unlike in the studies of Vyas et al (2014aVyas et al ( , 2014b. Animals used in the present study had no previous exposure to Propionibacterium strains thereby ruling out the possibility of any carry-over effects that might have confounded results in the present study.…”

“…Dietary treatments included: (1) Control, (2) Propionibacterium freudenreichii T114, (3) P. thoenii T159, and (4) P. freudenreichii T54. Strains were grown daily in sodium lactate broth under anaerobic conditions according to the method described earlier (Alazzeh et al 2013) and were administered daily (1 · 10 11 colony forming units) at the time of feeding directly into the rumen. Treatments were randomly allotted within each group.…”

“…The efficacy of Propionibacterium strains identified using an in vitro batch culture experiment as having CH 4 mitigation potential (Alazzeh et al 2013) needs to be validated in vivo before such a strategy can be recommended for lowering CH 4 emissions from beef cattle. Hence, the primary objective of this study was to confirm in vivo the efficacy of Propionibacterium strains previously identified in vitro as having the potential to mitigate CH 4 emissions in beef cattle.…”