Using data to cut dairy methane emissions
Carbon footprint and methane emissions are among the most prominent and urgent issues facing dairy farmers today.
Agriland talked to James Husband, senior livestock consultant for Map of Ag, about how data plays a part in cutting down methane emissions on farms.
Taking stock
Map of Ag is a software platform in the UK that organises information to help farmers reach more sustainable outcomes at scale.
Looking at inventory is an important first step in addressing emissions, according to Husband.
He said: “If you were doing a GHG [greenhouse gas] assessment over a set 12-month period, we would want sufficient data resolution to have a daily inventory of what animals were on the farms, their status, and their production to be able to do more accurate calculation of enteric emissions [methane gas produced during the digestive process of ruminant livestock]."
According to Husband, this is always the largest part of the overall emissions and also needs to be done as accurately as possible.
“Accurate animal inventories allow you to input into the enteric methane equations much more accurately than averaged figures across the different stock age groups over a year.
“So, we would use data from BCMS [British Cattle Movement Service] or you can use the Irish equivalent, the ICBF [Irish Cattle Breeding Federation]," he explained.
“With that, you would have very granular data on the numbers of animals that were on the farm, their status, whether they were lactating, whether they were dry, whether they were growing.
“You calculate a daily figure and sum these for the entire year.”
Feed
Another important metric is feed, which is a major factor when it comes to emissions.
“Embedded feed emissions are usually - for the farms that we will be looking at in the UK - the second biggest emission after the enteric emissions,” Husband said.
“It’s potentially a big proportion of emissions so, again, accuracy must be good.
“Embedded feed emissions are the emissions related to the production, manufacture, and transport of that feed to the farm.”
Other variables
For a farmer to get an accurate picture of their business, there are several variables.
Each one, Husband argued, helps paint a more accurate picture.
“Inorganic and organic fertiliser usage, storage, and application methods are important to calculate what are the methane and nitrous oxide emissions associated with [dairy farming].
“Emissions associated with fuel are relatively small compared with some of the areas mentioned so far.
“They are usually relatively easy to be accurate about, but their accuracy is not really as important as the ‘big ticket items’ which make up a large part of the emissions we have mentioned so far.
“The more information you can get, obviously, the more accurate you can be," he said.
Modelling a herd
At Methane Connect in Paris, Husband demonstrated how corresponding numbers on a farm impact one another in a cause and effect chain.
He said: “One of the reasons we made that tool that I showed in Paris was that you could say the farmers will be given a number, a GHG emissions intensity number, which for them can look like it's just come out of a black box, and [they] don't understand how that number was actually generated.
“And that's why we were quite keen to build something that was based on a very obvious life cycle analysis.
“So modelling a herd, you effectively create a digital twin of that herd, following a typical animal from birth, all the way through to the end of that individual animal's life.
“This animal can be extrapolated up to a herd level if that representative animal has the same number number of lactations as the herd average, the same average yield, age at first calving, and calving intervals, and has the same inputs in terms of feed and fertiliser."
According to Husband, these parameters, "which farmers understand and are hence more tangible", are easy to model.
He said this will help farmers "understand how much the GHG emissions intensity of their farms change as things like fertility, culling, feed rates, and fertiliser usage change".
The future of emissions
Husband remains optimistic about the future of dairy farming from an environmental and emissions perspective.
“What we're seeing across the dairy supply chains that we've worked with over the last 15 years is that the efficiency on farms is definitely getting a lot better,” he said.
“So we see lower levels of lameness, lower levels of mastitis and less cell count issues.
“We see lower levels of metabolic disease, even with increasing production. And we're still seeing progressive improvement in all these areas."
He added that the quality of management and the type of cows and genetics are "definitely improving".
“So I actually feel quite positive about it because things are improving all the time," Husband said.
“You are never going to knock big chunks off the GHG emissions, but it's going to come down incrementally as things improve and then there is scope for new technologies to improve things further.
“Generally, things are moving in the right direction.”
