Degree Name
Master of Science
Graduate Program
Animal Science
Advisor
AbuGhazaleh, Amer
Abstract
Changes in the climate continue to be one of the world's most pressing issues. The accumulation methane (CH4) in the atmosphere is a major driver of these changes. Ruminant animals have been identified as substantial contributors to CH4 emissions. This assertion is supported by the fact that ruminant animals have a unique digestive tract that allows them to digest complex polysaccharides by the action of microbes in their rumen. During the microbial digestion (fermentation) of dietary polysaccharides, CH4 is produced as a byproduct of the process. Therefore, this paper aims to analyze this issue, highlight how ruminants contribute to this phenomenon and suggest measures that can be implemented to mitigate CH4 production by these animals. Research studies in recent years have tested if different supplements may reduce CH4 emissions from ruminant animals by suppressing some of the methane-producing microbes in the rumen or by altering the hydrogen (H2) utilization in the rumen. Results in this paper showed that some of the tested supplements (e.g. Ionophores, tannins, essential oils (EO), nitrate, bioflavonoids, and enzymes) or their combinations can decrease CH4 production in the rumen without significantly affecting animals performance or rumen fermentation. However, the results were not always consistent depending on the supplement dosage and treatment diets composition. Although some of the tested supplements showed promising effects, more research is still needed to assess the long-term effects for some of these supplements as rumen microbial adaptation may weaken the reported effects.