Greener pastures for dairy farming
17 Jan 2022
Hay from the alfalfa plant, also known as alfalfa (Medicago sativa), is a high-quality structural component in the feed ration for high-performance dairy cows due to its high crude fiber content. Alfalfa is also rich in natural vitamins and nutrients - and dairy cows love to eat it.
Carolina Hennings, Product Manager for Automated Feeding Systems at GEA Farm Technologies, sheds new light on sustainability strides in the dairy farming industry and the seemingly small efficiency improvements making a sizable contribution to the climate fight.
As we come off the COP26 and see countries setting new carbon neutrality targets, industries such as meat and dairy are increasingly viewed as part of the climate problem rather than the solution. How do you see this?
One of the most important challenges connected to COP26 goals is: How can we feed a growing human population as sustainably as possible? At GEA we pride ourselves on the fact that our solutions are powering efficiency gains in a wide range of industries that are highly relevant to this – as well as our climate and sustainability – from food and new food to refrigeration, to dairy and to agriculture. This is where our solutions can have a really big positive impact.
And when we take a step back and consider the longer-term trends, we see progress being made. Take agriculture for example. This is a high impact area when you consider that agricultural activity accounted for 10 percent of the EU’s total greenhouse gas emissions in 2017. But this figure represents a significant improvement. The agricultural sector was in fact able to decrease emissions by 19 percent between 1990 and 2017.
What about dairy farming? Data from Germany indicates that livestock farming accounts for over half of agriculture’s emissions.
I think it’s important to consider the bigger picture here, too - because these data summarize different areas and factors from the overall livestock industry. If we focus on dairy farming, one trend stands out over the last several decades: more milk is being produced by significantly fewer cows. In the US, for example, the number of dairy cattle decreased by more than 50 percent between 1950 and 2000, while total milk production increased by over 40 percent. So productivity per cow more than tripled over that span. In Germany, the dairy cow population is down from 6.4 m in 1990 to about 3.9 m today. And over this period, milk production per cow in Germany (on average) has nearly doubled. Fewer dairy cows are feeding many more people, and this is largely due to advances in breeding, cow health, feeding and overall efficiency on the farm.
Does increased milk production per cow mean lower GHG emissions?
In fact, increasing the milk production per cow is considered a powerful strategy for reducing GHG emissions per kg of milk produced. There are some interesting numbers on this. A model introduced in 2011 (M. Zehetmeier et al.) shows that increasing a cow’s milk production from 6,000 to 8,000 kg per year translates into a decrease in GHG emissions per cow per year from 9,578 to 7,689 kg CO2. This decrease in GHG emissions is basically driven by the reduction of enteric fermentation, manure and soil N2O.
And this is an example of where automated feeding systems (AFS) can contribute. In our experience at GEA, AFS can increase milk production by 4 kg/cow/day or 1,220 kg a year – depending, of course, on the initial status of the farm’s feed management. This increased productivity is due to more frequent feedings (6 to 8 times a day), fresh mixes and the greater precision of AFS. This is a significant boost in production with a potentially significant impact on CO2 emissions.
How else can AFS boost sustainability?
There’s a reason why GEA has been in the dairy feeding automation business for over 35 years. Feeding automation makes a real difference for farmers – reducing labor time and energy costs while improving feed efficiency and milk production – especially when fine-tuned to the needs of individual farmers.
We spoke about the impact of increased cow productivity on CO2 emissions and the potential role of AFS in this equation. But AFS can also directly lower a farm’s carbon emissions because it runs on electric rather than diesel power. In our experience at GEA, a dairy farmer in a conventional feeding setting will use about 18 liters of diesel per cow per year for powering the mixer wagon. If we assume one liter of diesel burned generates 2.65 kg of CO2e, a farm with 200 dairy cows will emit some 9,540 kg of CO2e per year just to power the mixer wagon. An automated feeding system, on the other hand, runs on electricity.
According to research conducted in 2015 by the Bavarian State Research Center for Agriculture, a MixFeeder system consumes 21.36 kWh per animal per day. So if we assume that one kWh of electricity represents 336 grams of CO2e (figure for Germany in 2020) and apply this to the same 200-cow farm, we see that emissions generated by an automated feeding system are around 1,435 kg of CO2e a year. This is much lower than conventional feeding and a good example of the energy efficiency gains possible with AFS.
One of the selling points of AFS is less refusals, i.e. cows rejecting less of the feed that is offered. Can this also be considered a sustainability gain?
It is a bit harder to quantify the impact of this efficiency gain on CO2 emissions, but it is promising nevertheless. Partly because dairy farming is under increased scrutiny, we see more research being done on how different dairy farming activities impact greenhouse gas emissions, including assessing the environmental impact of improved feed efficiency in dairy cows. The RuFaS (Ruminant Farm Systems) model, for example, is used to predict the environmental impact of dairy production in four main areas; animal, manure, field and feed storage – all areas where work can be done to reduce GHG emissions. The model indicates that improvements in feed efficiency, ration formulation, feedstuff selection and energy source can have a positive impact on greenhouse gas emissions. And of course, reducing refusals has a positive impact on feed efficiency.
We are seeing significantly lower refusal rates thanks to AFS. If we assume 50 kg of mix ration per cow per day on a 200 cow farm, for example, we will have feed dispensing of 10,000 kg per day. In a conventional setting we see about 5 percent refusal on average. With automated feeding, this refusal can go as low as 1 percent, but we’ll assume 2 percent, which is in keeping with our experience at GEA. This means that our sample farm will have 500 kg per day of refusals in a conventional setting, but only 200 kg with automated feeding. This is a significant reduction in the feed waste on the daily level and is something that can really add up over the course of a year.
A career as a high-performance cow also starts with the right feed: a well-balanced calf TMR ensures good growth, health and wellbeing even for the youngest in the herd
You mention in earlier publications that feed additives can reduce methane and improve nitrogen utilization.
Yes, this is an example of how AFS can support faster progress in making farms more sustainable. Over the last several years, different companies have introduced additives to the market – to inhibit methane production or improve efficiency in the rumen, for example. The additives are included in the ration, and since we are talking about small quantities, proper mixing and distribution is key for the expected results. AFS create a controlled environment, which means the right amount of additive can be weighed with high precision scales, mix quality can be constantly monitored, and additive amounts can be adjusted to the different groups. So looking forward, AFS offer the precision and systematization you need to test and further develop these kinds of feeding innovations.
It seems like the original goal of automated feeding was to save labor and time, but it turns out to offer a range of different sustainability benefits.
That’s right. We find that farmers who transition to AFS notice the labor savings most obviously and most immediately. But over time, the ability of AFS to boost productivity, improve energy efficiency and feed efficiency, and reduce feed waste really starts to impact a farm’s environmental performance.
So as governments implement regulations and create subsidies to support greener technologies, feeding automation technologies should be considered an important part of the “mix” – as effective tools for improving a farm’s profitability and sustainability. These are small but significant steps that will make sure we maintain the steady progress we’ve seen over the last several decades in agriculture and dairy – to make sure we keep feeding all people while steadily reducing our carbon footprint.
