Livestock farmers are under increasing pressure to reduce their environmental impact and dairy farming in particular is affected with almost 40% of emissions from methane produced as a consequence of ruminant fermentation.

In a bid to combat this, Mole Valley Farmers is incorporating methane output into its precision nutrition ration programme to give farmers a greater understanding of how different diets impact on the environment.

The new programme, which was launched at Dairy-Tech, at Stoneleigh Park on Wednesday, is able to predict the grams of methane per cow per day produced and grams of methane per litre that a specific ration is likely to produce, based on its nutrient profile. This is calculated using an equation which has been carefully selected from peer reviewed literature to complement UK dairy systems.

The decision to look at methane in detail follows research carried out by Harper Adams University in conjunction with Mole Valley Farmers. The work looked at methane output on different diets and found that rations based on maize silage and starch reduced daily methane emissions by about 7%, compared to grass silage and higher fibre diets.

With the NFU setting a target for farming to become net zero by 2040, having the tools in place to understand farming’s true impact on the environment is essential, says Mole Valley Feed Solutions technical manager, Dr Matt Witt.

“Although there’s currently no penalty or reward for producing more or less methane, it’s likely these parameters will become more important in terms or milk payments, support payments or both. We want to be prepared for that,” said Dr Witt.

“We want to try and put a bit of realism into the debate around cows and the environment. Having figures on methane will allow us to benchmark so we are in a better position to help farmers plan for the future.

“We’ll start to get a feel for what the numbers look like, how they are influenced by diet and how they link to other key drivers of profitability.”

As the system develops and is fully understood, Dr Witt has three main ways in the short-term that dairy farmers can reduce methane emissions:

1. Improve cow longevity and fertility – If cows are fertile and live longer, replacements rates will be lower, reducing the number of heifers on the ground and lowering methane output.

2. Avoid excessive fibre levels as part of a balanced diet – Avoiding excessive levels of fibre, whilst maintaining good ration balance for production, can help lower methane emissions. For example, a realistic diet of 32% NDF versus a diet of 40% NDF will produce around 5% less methane, according to precision nutrition calculations.

3. Produce more from less cows – Raising output per cow can enable cow numbers to be reduced, thus benefitting the environment.