|
Methane abatement strategy | Mechanism of abatement activity | Considerations when selecting abatement strategy |
|
Dietary composition | | |
Increase hemicellulose/starch Decrease cell wall components Grinding | Increased passage rate; greater proportion propionate versus acetate; reduced ruminal pH | Shift methanogensis to hind gut or manure, risk of subacute ruminal acidosis (SARA) |
| | |
Lipids | | |
Fatty acids Oils Seeds Tallow | Inhibition of methanogens and protozoa; greater proportion propionate versus acetate; biohydrogenation | Effect on palatability, intake, performance, and milk components; varies with diet and ruminant species; long-term studies needed |
| | |
Defaunation | | |
Chemical Feed additives | Removes associated methanogens; less hydrogen for methanogenesis | Adaptation of microbiota may occur; varies with diet; maintenance of defaunated animals |
| | |
Methanogen Vaccine | Host immune response to methanogens | Vaccine targets; diet and host geographical location differences |
| | |
Monensin | Inhibits protozoa and gram-positive bacteria; lack of substrate for methanogenesis | Adaptation of microbiota may occur; varies with diet and animal; banned in the EU |
| | |
Plant Compounds | | |
Condensed tannins Saponins Essential oils | Antimicrobial activity; reduced hydrogen availability | Optimum dosage unknown; more in vivo research needed; long-term studies needed; may affect digestibility; residues unknown |
| | |
Organic Acids | | |
Fumarate Malate | Hydrogen sink, greater proportion propionate versus acetate | Varies with diet; more in vivo research needed; long-term studies needed; may affect digestibility |
|