Performing Department
(N/A)
Non Technical Summary
Besides being a potent global warming gas, enteric methane from ruminants represents arelevant source of feed inefficiency by sequestering 3-12% of the energy intake. However, directinhibition of rumen methanogenesis has not consistently increased energy capture from the diet.Nevertheless, to translate methane inhibition to feed efficiency improvements, the conservedenergy needs to be rerouted towards the synthesis of nutritionally relevant metabolites for theanimal like ruminal propionate. The inconsistent improvements in production parameters as aresult of direct inhibition of methanogenesis, suggests that spared energy is being alternativelyredirected towards other pathways.We demonstrated that feeding cattle novel probiotics composed of competitive keystonerumen-native succinogenic bacteria isolated from the rumen of feedlot steers, improved growthperformance parameters, decreased methane emissions yield, and modified the composition ofthe rumen microbiome. These keystone probiotics, which already successfully competed withmethanogens in vivo, hold great potential to thrive and divert the conserved energy towardspropionate production in a methanogenesis-inhibited rumen environment. Therefore, wehypothesize that the use of rumen-derived succinate-producing bacteria, together with a potentmethane inhibitor, can constitute an innovative approach to reduce methane emissions while alsofurther improving feed efficiency in beef cattle. The objective of our research project is to testthe above hypothesis using a combination of the new probiotics (rumen-native succinogenicbacteria) and red algae (Asparagopsis taxiformis). The outcomes of this research will not onlymitigate methane emissions and support a more sustainable beef production, but will also benefitproducers economically due to growth performance improvements.
Animal Health Component
80%
Research Effort Categories
Basic
20%
Applied
80%
Developmental
(N/A)
Goals / Objectives
Significant reductions in enteric methane (CH4) emissions with concomitant improvements ineconomic returns for cattle producers are critical for the 2050 climate neutrality commitmentand the sustainability of the cattle industry. Our long-term goal is to better understand theruminal H2 dynamics and metabolism in a methanogenesis-inhibited rumen environment todevelop nutritional strategies able to translate CH4 emission reductions into feed efficiencyimprovements. The proposed research builds upon our recent findings that feeding beef cattlethe succinate-producing bacteria Chordicoccus furentiruminis and Succinivibrio dextrinosolvens,isolated from the rumen of highly efficient feedlot steers, decreased CH4 emissions andimproved productivity by modifying the rumen environment (Pittaluga et al., 2023). Ourcentralhypothesis for the research proposed in this project is that including rumen-nativesuccinogenic bacteria in diets along with the potent methanogenesis inhibitor bromoformrichred macroalgae A. taxiformis will help divert the energy spared from CH4 productiontowards nutritionally beneficial metabolites for cattle. Our objectives are i)To evaluate the effect of A. taxiformis supplementation individually or incombination with a mixture of two rumen-native succinate-producing bacteria (C.furentiruminis and S. dextrinosolvens, referred to as probiotics hereafter) in vitro.; and ii)To evaluate the effect of including A. taxiformis individually or incombination with probiotics to feedlot cattle diets on growth performance, gas emissions,rumen metabolites, microbial functions, and the associated changes in the taxonomiccomposition of the rumen microbiome.
Project Methods
We will first identify the optimum doses of the A. taxiformis in batch cultures to achievesignificant reductions of CH4 production while minimizing the adverse effects on anaerobicfermentation. Using the previously determined optimum dose of A. taxiformis, we will thenanalyze the dynamics and rumen microbiota regulation of the dH2 flux towards potential dH2-consuming pathways as a result of adding rumen-native succinate producing bacteria in dualflow continuous cultures. We will then proceed to validate in vivo the results obtained from thein vitro experiments, where we will also evaluate growth performance parameters as well asthe dynamics of dH2 flux when including rumen-native succinate-producing bacteria to a CH4-inhibitedrumen environment. We will apply a system-wide approach by integrating ruminaltranscriptomic with metagenomic data and metabolites analysis to characterize the response ofpotential dH2-consuming pathways to the treatments. We will use state-of-the-arttechnologies, like the GreenFeed system, to analyze gas emissions,as well as integrated omicstechniques to evaluate changes in the rumen microbiome and its functionality.The outcome of this research will provide evidence of how the decrease in CH4 production (in vitro and in vivo) can results on an increase of animal growth and feed efficiency. For that reason, the result will be presented in formal classroom settings, for the students to understand the biology and implications of the decrease in CH4 production. We will present the data in extension presentations and research articles, but the usage of the methodology will depend not only on the increase of production that the animals have, in case our hypothesis is correct, but also on the cost of the products, and the creation or not of incentives to decreased CH4 production.