Elucidation of the dynamics of the rumen microbiome and metabolic hydrogen
Background
The rumen is the first of four compartments of the stomach in ruminant animals such as cattle. Rumen microorganisms play an important role on fiber degradation. Forage-based feeds are fermented by bacteria in the rumen and transformed into volatile fatty acids(VFAs) for nutrients of cattle. At the same time, methane is produced by methanogens from CO2 and metabolic hydrogen formed during the microbial fermentation. Metabolic hydrogen is also consumed in propionate production. Therefore, stimulating propionate fermentation in cattle might be lower methane emission.
Research content
(1) Identification of novel methane-suppressing bacteria and theirrelationship to the rumen microbiome.
We have successfully identified and isolated a new rumen microorganism from the rumen of dairy cows that is expected to enhance propionate production. And we aim to develop microbial materials that inhibit methane production over the long term by establishing novel culture and preservation techniques.
(2) Elucidation of the dynamics of metabolic hydrogen in the rumen and development of a mathematical model of the rumen microbiome
Dairy cows repeat the cycle of calving, 280-300 days of lactation, 60-90 days of dry period, and the next calving. The composition of the rumen microbiome changes significantly due to the amounts and the kinds of feeds changes during this period, but the dynamics of metabolic hydrogen during this period are not known. We will suggest the models for estimate the methane production according to the feeding program by visualizing the metabolic hydrogen flow through mathematical analysis. We aim to contribute to optimal feeding management technology that can suppresses methane production and increase productivity of cattle.
Subprojects
Subproject 1: Understanding of rumen microbiome and metabolic hydrogen flow
Subproject 2: Development of “smart pill” for real-time monitoring of rumen fermentation
Subproject 3: Establishment of optimal feeding system for reducing rumen methane