How to reduce methane emissions from cattle: strategies for mitigation and sustainable livestock production

As the demand for meat and dairy products continues to rise, finding effective methane mittigation strategies for cattle is crucial to reach targets to reduce methane set by governments and milk processors. In this article, we will explore various mitigation strategies to reduce methane.

To meet the increasing demand for dairy products sustainably, researchers have identified several product-based strategies to reduce methane from cattle¹. One of the options to reduce methane is to make cows more efficient. This is sometimes referred to as “product based strategy”. Product based strategies focus on reducing methane emissions per kilogram of milk produced. They are based on indirect methane reduction. These product-based strategies aim to enhance productivity while reducing methane emissions, creating a more sustainable and efficient livestock production system.

Methane emissions intensity, defined as kg CO₂ equivalents per kg of milk produced, will go down significantly if milk production increases (see Figure 1).

A big opportunity for reducing methane emissions would be to increase feeding levels in low-income countries, where there is room to provide more energy to animals. By doing so, methane emissions reduction per kilogram of milk can be achieved. Additionally, managing grass maturity and optimizing the nutrient profile of grass can contribute to methane emission reduction. Another effective approach is adjusting the dietary forage to concentrate ratio, which helps optimize the animals' digestion and subsequently reduces methane emissions.

A high correlation has been found between feed efficiency and methane production, which has important implications for reducing methane emissions. Cows were tracked at five commercial farms, examining the performance of the top performing quarter and the least efficient quarter. The least efficient cows tended to eat more dry matter and concentrate than highly efficient cows and produced about 10 kg less milk per day. In addition to producing more and eating less, methane emission reduction was found in the highly efficient cows (see Figure 2). The highly efficient cows also produced less manure which resulted in a further methane reduction.

Lifetime Daily Yield can be increased by reducing the age at first calving, by increasing the production per lactation and by increasing the number of lactations per cow. Reducing the age at first calving will reduce methane because methane emissions during the rearing period are less. Studies carried out by the ILVO in Belgium² showed that a methane emissions reduction of 3.1% can be achieved by reducing the age at first calving from 26 to 24 months.

If the production per lactation goes up, methane reduction occurs, as methane produced when the cow uses energy for maintenance is diluted over more kilograms of milk. The same study carried out by the ILVO² showed that reducing methane emissions by 8.4% is possible by increasing average production from 27 to 30 kg per day.

Increasing the number of lactations is also a viable approach, as methane produced during the rearing period is diluted over more lactations. Management programmes to increase the number of lactations per cow will also increase milk production per lactation, resulting in a further methane emissions reduction. Studies carried out by the ILVO² showed that a reduction of the culling rate of dairy cows by 5% results in an average increase of milk production per day of 3 kg, which will be reducing methane emission per kg of milk produced by 11.7%.

Advancements in genetics and farm management have played a significant role in increasing the productivity of dairy cattle and reducing methane emissions. From 1960 to 2000 wows were bred mostly for milk and fat yield, as well as body type. This resulting in selection for greater feed efficiency and methane emissions reduction per liter of milk. We also selected for larger cows and those larger cows have a higher maintenance per unit body weight, making them less efficient.

Methane emission is a heritable trait, which is permanent and cumulative. Correlations have been established between milk mid-infrared (MIR) spectroscopy and methane emissions. Genetic selection therefore can be an effective methane mitigation strategy. It is believed that genetic selection has the potential to reduce methane by 11-26% in 2030.

There are a number of feed additives for dairy cows that increase milk production without increasing dry matter intake. If the dry matter intake does not increase, total methane emission does not increase either. As a result, the amount of methane per kg of milk produced will be reduced. Increasing feed efficiency with feed additives is therefore a viable approach for methane mitigation. Selko IntelliBond and Selko Fytera Balance are examples of Selko feed additives for ruminants that reduce methane indirectly.

Absolute reduction strategies for cattle methane emissions

Apart from product-based strategies that increase feed efficiency, absolute methane reduction strategies play a vital role in methane emission mitigation programmes. These strategies focus on reducing the absolute amount of methane emitted, irrespective of the amount of milk produced. One approach involves the use of methane inhibitors, which are substances added to the animal's diet to inhibit methane production in the rumen.
Similarly, incorporating plant extracts and specific types of fats in the diet can contribute to reducing methane emissions. Selko Fytera Balance is a product with a combination of two plant extracts. It has been shown to provide a direct methane emission reduction of 8-10%^3,4,5.

The progress made in reducing methane emissions from cattle is significant, with methane emission intensities decreasing by 45% over the last 50 years⁶ (see figure 3). However, further advancements and technological innovations are necessary to achieve even higher methane emission reductions. Continued research, including the development of software tools for low-income countries, will aid in improving productivity and ensuring sustainable practices that reduce methane.

Reducing methane emissions from cattle is crucial for mitigating climate change and creating a more sustainable future. Strategies such as adopting product-based and absolute methane mittigation strategies, and focusing on genetic gains and improved farm management have shown promising results. By implementing thesemethane reduction strategies and promoting sustainable livestock production, we can effectively reduce methane emissions from cattle and contribute to a healthier planet for future generations.

• Increasing feed efficiency: 0.47 to 0.8% per year⁷
• Feed additives: 2 to >12% per year⁸
• Genetic selection: 11-26% by 2030
• Manure management, anaerobic digester: 15 to 25% per year
• Covered storage: 15 to 25% per year