Feed additives to reduce methane in cattle

Governments and milk processors are setting targets for reduction of methane because they want to reach the reductions agreed for 2030 and 2050. Those targets can not be met by only using feed additives to reduce methane, but methane reducing feed additives can make an important contribution. Discover which feed additives for cattle to reduce methane are available and find out which of those feed additives to reduce methane do not increase the costs per kg of milk produced.

Depending on the production level, stage of lactation and ration, about 40% of the total methane emission of a farm comes from enteric methane production in the rumen (See figure 1). This means there is a difference between reducing the level of enteric methane emission and reducing the level of total methane emission. For example, a methane reducing feed additive that reduces enteric methane by 30% will reduce total methane emission by about 12%.

There are feed additives to reduce methane emission with a direct effect on methane production in the rumen. Such a feed additive curbs methane emission from dairy cows because it changes the rumen fermentation process. However, these methane reducing feed additives cost money but they don’t increase milk production and thus increase the cost per liter of milk produced on the farm.

Alternatively, there are feed additives to reduce methane with an indirect effect on methane emission of cows. These feed additives for cattle to reduce methane increase feed efficiency. The cow will continue eating the same amount of feed, with a fixed production of methane, but she will produce more milk. As a result, methane emission per kg of milk is reduced. Feed additives to reduce methane which have an indirect effect on methane emission have the advantage that they do not increase the cost per liter of milk produced on the farm. In fact, they increase feed efficiency and thus have the potential to reduce the cost per kg of milk produced.

Feed additives to reduce methane like Selko IntelliBond reduce methane because they improve feed efficiency. A trial carried out by the Ohio State University^[1] showed that completely replacing sulfates trace minerals in the ration with Selko IntelliBond improves fibre digestibility of dairy cows. This has been confirmed in several peer reviewed studies^{[2,3,4,5,6,7,8]} (see Figure 2). Each one point difference in NDF digestibility can increase milk production by 0.25 to 0.3 kg of Energy Corrected Milk^[9].

Several trials^[10,11,12] have confirmed that Selko IntelliBond increases milk production in dairy cows. Selko IntelliBond is herefore an example of a methane reducing feed additive which reduces methane emissions per kg of milk produced, while reducing the cost per kg of milk produced.

Dr. E. Kebreab, Professor at the University of California, Davis, evaluated the effect of replacing sulfate trace minerals with Selko IntelliBond trace minerals. Professor Kebreab concluded that feeding Selko IntelliBond trace minerals reduces total methane emission by 1.5-2.0%. This makes Selko IntelliBond the world’s first trace mineral feed additive to reduce methane with an official endorsement and a certificate for methane reduction per kg of energy corrected milk in dairy cattle.

Another Selko methane reducing feed additive is Selko Fytera Balance. The product combines an improvement of feed efficiency with a reduction of 8-10% of direct methane emission from the rumen, resulting in a reduction of 5-6% of total methane emissions^[13,14,15] (see Figure 4). Selko IntelliBond and Selko Fytera Balance are feed additives to reduce methane that work through different modes of action. Therefore, with these two Selko methane reducing feed additives combined, a total reduction of 8% of total methane emission is achievable.

Silage preservatives

Other opportunities exist to reduce methane emissions from ruminants. Silage preservation can have an impact on both the microbial quality, nutrient level and the palatability of a silage. If the silage quality is not managed properly, feed intake and milk production will be reduced, making milk production less efficient. Silage inoculants or silage preservation products such as Selko Fyvalet Silage, can improve the quality of silage and are therefore potentially feed additives to reduce methane. The impact of silage preservation products on silage quality varies enormously between farms, it is therefore very difficult to quantify the impact on farm methane emission of these methane reducing feed additives.

TMR quality

Microbial growth in a TMR can also have a strong negative impact on nutritional value of the TMR and rumen health of dairy cows. TMR conservation products such as Selko TMR will therefore improve the quality of the TMR and increase feed intake, which in terms increases efficiency of milk production. A recent trial in animals that were subject to heat stress conditions showed an increase in milk production of 1.7 kg ECM per day in animals treated with Selko TMR Dry¹⁶ without an increase in dry matter intake. Also for TMR preservation products, the impact on feed efficiency and methane reduction varies per farm. Next to that, there is seasonal variation, making the effect of these feed additives for cattle to reduce methane a bit unpredictable.

Neutralizing the effect of aflatoxins

Contamination of dairy feed with aflatoxins may result in rejection of milk, which means the cows will produce methane, but no milk. Contamination of dairy feed with other mycotoxins can have a strong negative impact on rumen health, leading to a reduction of milk production. Selko TOXO MX has been shown to reduce the risk of contamination of milk with aflatoxins¹⁷. Selko TOXO HP-R has been shown to increase milk production in animals fed a diet contaminated with aflatoxins, without increasing dry matter intake, resulting in a reduction of methane emission per kg of milk produced¹⁸.

There are feed additives to reduce methane on the market that can reduce total methane emissions of dairy cattle by about 12%, but they do not increase feed efficiency. Feed additives for cattle to reduce methane such as Selko IntelliBond and Selko Fytera Balance increase feed efficiency and reduce the cost of milk production. With these two methane reducing feed additives, a reduction of methane emission of about 8% is achievable. The ideal feed additives to reduce methane should combine a reduction of at least 15% of total methane emission with an increase of milk production, thus reducing the cost of milk production significantly. The quest for such methane reducing feed additives for cattle is ongoing!

Manure additives to reduce methane emissions from ruminants

Methane from manure makes a significant contribution to total carbon footprint of a farm. Manure additives to reduce the carbon footprint should ideally reduce emission of methane but also of nitrous oxide and ammonia from manure, which in term should improve lung health of the animals in the barn. These manure additives should also increase the biogas yield in a bioprocessor and increase the nutrient value of the manure for plants, allowing for a reduction of the use of synthetic fertilizer. Lastly, the ideal manure additive should also improve soil quality once the manure is brought on the land. Compared to feed additives to reduce methane, reductions of methane emission per animal, similar or higher are possible.