Feed Fat and Methane Reduction
Methane (CH₄) emissions have become a significant topic of concern, not just from an environmental standpoint but also for their impact on profitability and future regulatory compliance. As the industry faces growing pressure to reduce its environmental footprint, farmers and nutritionists must start planning ahead to adopt sustainable practices that align with both economic and environmental goals.
In this episode of our Why Feed Fats series, Dr Richard Kirkland, Global Technical Manager at Volac Wilmar, explores how rumen-protected fats can help dairy farmers reduce methane emissions and improve feed efficiency. He explains how the right feeding strategies can address both environmental and economic challenges that the dairy farming community faces today.
Why Methane Matters to Dairy Farmers
Methane emissions represent a loss of valuable dietary energy, accounting for between 2% and 12% of energy loss in a typical dairy cow’s diet. This inefficiency can significantly impact profitability, as a 10% energy loss in a Holstein cow equates to approximately a 5 kg reduction in milk production.
Moreover, dairy farmers are likely to face stricter regulations around methane emissions in the coming years. Driven by consumer demand, processor policies, and government mandates, the industry must start implementing mitigation strategies now to stay ahead of these changes.
How Rumen Function Affects Methane Production
Methane is produced during the fermentation of fibre in the rumen. While reducing fibre intake might seem like a straightforward solution, it can lead to health issues like acidosis. Instead, improving the digestibility of both fibre and fat in the diet is a more effective strategy.
Rumen-protected fats, such as Megalac, enhance digestibility and shift the fermentation pattern in the rumen. By optimising rumen fermentation, these fats can lower methane production without compromising milk yield or cow health.
One notable study demonstrated that when Megalac was added to the diet of lactating dairy cows, it resulted in a 13.3% reduction in methane production per litre of milk. This was achieved by replacing fermentable corn with Megalac, which not only reduced methane emissions but also increased milk yield by 2.1 kg per day. This trial used respiration chambers to measure methane production, highlighting the effectiveness of Megalac in reducing methane emissions in a controlled environment.
Planning for a Sustainable Future
Incorporating rumen-protected fats into dairy cow diets offers a practical solution for reducing methane emissions while boosting feed efficiency and milk production. As the industry prepares for more stringent environmental regulations, these strategies will be essential for dairy farmers who want to remain profitable and sustainable.
Watch Episode 4 of our Why Feed Fats series where Dr Richard Kirkland discusses the benefits of using rumen-protected fats to reduce methane emissions and enhance dairy cow productivity.
Watch the video now, or scroll down to read the full transcript. Why Feed Fats, Episode 4
Why Feed Fats, Episode 4 transcript:
My name is Richard, and I'm Global Technical Manager here at Volac Wilmar Feed Ingredients. Welcome to our next episode in the Why Feed Fats series. In this episode, we'll be looking at how we can use rumen-protected fats to reduce methane production in dairy cows.
Methane is a really hot topic when we're looking at greenhouse gases on dairy farms. From both an environmental perspective and an animal nutrition perspective, it's really important that we look at how we can take mitigating measures to reduce methane production. From an environmental perspective, we know that methane has a global warming potential about 30 times higher than that of carbon dioxide, so has a real negative effect on global warming. But from the dairy cow perspective, we know that around 6 to 8% of the energy consumed by the dairy cow will be lost as methane, which is a real direct energy loss of the diet energy. So if we're able to take measures to reduce methane production, then we can save that energy which can be used for productive purposes such as more milk, more milk solids, body condition, or to help cow fertility.
In the dairy cow, methane is primarily produced due to the fermentation of fibre in the rumen, so as we get more and more fibre in the ration that will be fermented to acetate and butyrate, which will lead to increases in methane production. If we have lower fibre diets, then we would generate more propionate as a volatile fatty acid, which will actually reduce the proportion of methane produced.
We need to be really careful in terms of our balance of our fibre and starch in the ration. Higher fibre rations will generate more methane, and higher starch diets will generate less. But we need to be really careful in terms of the fibre balance and starch balance that we don't lead to issues of acidosis caused by high starch rations and similarly low milk fats because we've got high starch and low fat.
With fibre being the main source of generation of methane in the rumen, we could look to simply reduce the proportion of fibre in the ration. However, we need to be really careful with reducing fibre in the ration as we could end up having negative effects on productivity, in particular in terms of rumen health in relation to acidosis or the effect on low milk fat, for example.
So it's really important as we try to tackle methane reduction, we don't do it in a negative way that will have a negative effect on other aspects of cow health or production. We want to maintain fibre level to ensure we have rumen health, and we ensure we are able to produce maximum levels of milk fat, but we don't want to exceed the level of starch in the ration where we will have a negative effect on rumen function, particularly the big risk of increasing risk of acidosis.
Another way we can reduce methane production in dairy cows through dietary means is to increase the proportion of rumen-protected fat in diets. The key difference between rumen-protected fats and other ingredients we will have in the diet is that rumen-protected fats are not fermentable. If we don't have the fermentation in the rumen, we will not generate methane. So that's the unique aspect of fat as an ingredient - it will not lead to the generation of methane. The key difference when we're looking at individual ingredients and trying to produce a balanced diet, which will not only reduce methane but also give us the productivity benefits, is that rumen-protected fats will increase the energy density of the ration so will supply more energy for milk yield, milk fat, body condition, and cow fertility. But crucially unlike all the other materials, they will not be fermented in the rumen, and they will not lead to the generation of methane. So we get higher productivity, we get lower methane, and we get much more efficient diets.
Volac Wilmar have just completed a fairly extensive project over at Cornell University in the USA. In that study, we looked at different types of rumen-protected fats which was the Megalac (the calcium salt supplement), and a high-C16 (high palmitic acid) product. We fed those at different levels of inclusion in the diet, so a 0%, a 1.5% or a 3% inclusion on a dry matter basis of the rumen-protected fat. In summary, for the project, we increased milk yield by over three litres per cow per day with the Megalac supplement. When we looked at the methane production, we reduced methane by over 6% methane per day at the highest level of rumen-protected fat inclusion. But when you look at that on a milk production basis, we found that methane was reduced by over 15% per litre of milk.
That's it for this episode of our Why Feed Fat series, but please join in for the next episode where we will be looking at how we can use the Volac Wilmar Fat Calculator to determine how much fat we should be feeding to our dairy cows.