Feeding Strategies for Methane Reduction on Farm

What are the greenhouse gases?

• Carbon Dioxide

• Methane

• Fossil Methane

• Nitrous Oxide

Carbone Neutral

anthropogenic Co₂ emissions associated with a subject are balanced by anthropogenic CO₂ removals

Net Zero

anthropogenic CO₂ or GHG are balanced by removals

Climate Neutrality

achieving no additional climate impact on a specific scale

Net Zero Warming

activities from an entity would not lead to additional warming

Global Warming Potential (GWP)

• Carbon Dioxide Equivalent CO₂e

• Goal: provide a common “currency” in which to compare emissions of different GHG

  • considers the global warming potential of a gas over a specified time horizon and the radiative efficiency of the gas

    • 20 year and 100 year horizons are commonly used

• Especially important to understand how calculated for the dairy industry because methane has a higher GWP than Carbon dioxide

GWP=CO₂ equivalent

everything is compared to CO₂

Stock Gases

stock gases will accumulate overtime because they stay in the environment

Flow Gases

Flow gases will stay stagnant as they are destroyed at the same rate as emissions, they go through a cycle

GWP*

• A problem with GWP is that it compares on a stock basis (mass of CH4 equivalent to mass of CO₂ )

• Another alternative, GWP*, attempts to respect the stock/flow distinction by relating the one-time release of CO₂ to an increased or decreased rate of CH4

• Also called CO₂we

GHGs from US Agriculture and Dairy

Dairy accounts for 2% of GHGs within the 10% that ag contributes

72% of Dairy GHG emissions occur before milk leaves the farm

1. Feed

2. Enteric

3. Manure

4. Energy

Methane Emissions from the Cow

• ~95% from belching and regurgitation

• ~5% from manure

Microbiology of Rumen Methanogenesis

there are methanogens that make up 10⁶ cells/mL

Value in the Product- Highest Nutrient Density

Milk has the highest nutrient density of all other beverages

Dilution of Maintenance

For a high producing cow more of her energy goes towards milk production than maintenance from feed consumed, therefore she is more efficient

What are the different ways to measure and quantify methane?

• Prediction models

• Respiration Chambers

• GreenFeed

• Breath Sampling

• Tracer gas

• Laser

Enteric Methane Mitigation Strategies

• Feed processing

• Genetic selection

• Improving animal health

• Improving pasture management

• Increasing feeding level

• Increasing forage quality

• Optimizing temperature

• TMR feeding

Nutritional Mitigation Approaches

• Concentrates

  • higher starch concentrates

  • less CH4

  • Increase propionate and butyrate

  • Animal health, land use, human food competition

• Forages

  • improved forage digestibility

  • Digestibility= increased energy for the cow= increased productivity

  • Improve CH4 intensity, absolute CH4 may not decrease

• Lipids

  • decrease methanogenesis by decreasing fermentation, decreases methanogens and protozoa, alternative H sinks through biohydrogenation of unsaturated FA

Animal Breeding and Genetics

• An individual cow’s CH4 is influenced by the host’s genotype, rumen microbiome, and the diet

  • ~20% of CH4 emission variation can be attributed to host genetics

• Assessing CH4 phenotype can be challenging

  • Need CH4 for extended period, production (lower emissions, but not at the cost of productivity/feed efficiency)

Inhibition of Rumen Methanogenesis

• Chemical inhibitors

• Seaweed supplements

• Nitrate

• Phytocompounds

• Early life programming

• Vaccination

3-NOP or Bovaire

a drug approved by the FDA decreases CH4 by ~30%, has also been fed to calves and the question is can you program the calf early in life to reduce emissions?

What does the zootechnical term refer to?

modification of the rumen

Innovative FEED Act

• To amend the Federal Food, Drug and Cosmetic Act with respect to the regulation of zootechnical animal food substances

  • added to food or drinking water of animals

  • Is intended to…

    • affect the byproducts of the digestive process of an animal

      • reduce presence of foodborne pathogens

    • Affect the structure or function of the body of the animal, other than by providing nutritive value, by altering the animal’s GIT microbiome

  • Achieves its intended effect solely within the GIT of the animal