News
September 23, 2026
In Denmark, Bovaer® has been the subject of intense discussion, with some farmers raising concerns about animal health and herd performance. This article adds another perspective by presenting on-farm data from five Danish dairy farms that used Bovaer® in 2025 and 2026 under real commercial conditions. Across these farms, the available records show neutral to positive impact on animal health, milk quality, feed intake or farm performance, while milk production and feed efficiency remained stable or improved on several farms.
When Bovaer® was introduced across Danish dairy farms in 2025 as part of Denmark's efforts to reduce agricultural methane emissions, it quickly became one of the most discussed topics in the sector.
Many farmers integrated the product into their feeding programmes without difficulty. At the same time, some producers reported concerns about herd performance and animal health, concerns that were widely discussed in farming communities and echoed in the media. For many farmers, this created uncertainty and raised an understandable question:
Much of the public debate focused on individual observations and personal experiences. Yet relatively little attention was given to the experiences of farmers who continued using Bovaer® and the farm data they were collecting throughout the process.
To help provide that perspective, we followed five Danish dairy farms during 2025 and 2026. Their farms differed in size, breed and management approach, but each integrated Bovaer® under normal commercial conditions and tracked performance over time.
Their stories do not erase the questions that were raised in 2025, nor do they suggest that every farm's experience will be identical. Instead, they offer something that has often been missing from the discussion: real-world experiences from Danish farmers combined with practical farm data gathered during the first years of Bovaer® use.
Together, these experiences provide insight into how Bovaer® was incorporated into everyday farm routines, what farmers observed and why many chose to continue using it after gaining experience with the product themselves.
The data were collected on the condition that the participating farmers would remain anonymous. For this reason, farms are identified by number only, and herd size is described relative to typical dairy farm sizes in Denmark. In 2026, the average Danish dairy herd counted 263 cows.
| Dairy cows/farm | Classification |
| <225 | Small |
| 226-300 | Medium |
| 301-400 | Medium-Large |
| >401 | Large |
The selected herds are at or above the Danish national average for milk production and feed intake. Their rations vary according to farmer preference and farm region. As a general guideline, dairy rations should contain more than 30% NDF to help avoid metabolic issues, and in high-yielding dairy cows, more than 75% of NDF is generally recommended to come from forage. Most of the farms reached or came close to these guideline levels. A small number operated with more challenging rations but did not experience production or herd-health issues. This illustrates why ration guidelines should be considered alongside the full farm context if problems arise.
| Farmer | Ration NDF, % DM | NDF from forage, % | DMI, kg | ECM, kg/year |
DK1 | 30.3 | 78 | 25.2 | 11 747 |
DK2 | 28.0 | 68 | 29.7 | 13 448 |
DK3 | 28.8 | 75 | 27.8 | 12 891 |
DK4 | 33.5 | 72 | 22.9 | 11 758 |
DK5 | 29.8 | 78 | 28.1 | 13 475 |
Data in table from March 2026
The five Danish farmers in this report used Bovaer® at the recommended dose of 60 mg 3-NOP/kg DM, without phasing it in from lower to higher doses at the beginning of each Bovaer® period.
This small-sized Holstein farm was among the early adopters of Bovaer® in Denmark. The farm first used Bovaer® from 1 February to 22 April 2025. In 2026, the farmer decided to use Bovaer® for 365 days.
For the farmer, the first year of use was reassuringly straightforward. No operational challenges were reported, no concerns were raised about cow health, and Bovaer® quickly became part of the normal feeding routine.
The farm's production records reflected that experience. During the monitoring period in 2025, energy-corrected milk (ECM) increased by 2.3%, dry matter intake (DMI) increased by 2.2%, and feed efficiency remained essentially unchanged. In 2026, ECM increased by 2.8%, DMI by 0.4% and feed efficiency by 2.1%.
Farmer takeaway: "Using Bovaer® became part of our routine without creating additional concerns or management challenges."
Key Results in 2025 (February to April)
| Indicator | Results | Change During Bovaer® Use |
| ECM | 35.0 – 35.8 | +2.3% |
| DMI | 23.0 – 23.5 | +2.2% |
| Feed Efficiency | 1.52 – 1.52 | 0% |
Key Results in 2026 (January to May)
| Indicator | Results | Change During Bovaer® Use |
| ECM | 36.1 – 37.1 | +2.8% |
| DMI | 24.9 – 25.0 | +0.4% |
| Feed Efficiency | 1.45 – 1.48 | +2.1% |
This small-size Holstein farm used Bovaer® during two separate periods: from 5 October to 31 December 2025 and again from 1 January to 1 June 2026.
Throughout both periods, the farmer reported a smooth experience with no concerns related to implementation or herd management.
As records accumulated, the farm observed encouraging results. In 2025, milk production increased by 4.7% while feed intake decreased by 5.3%. During the period, feed efficiency increased by 10.2%. The farm manager changed during the period, so it is difficult to state how much of the production increase should be attributed to Bovaer® and how much was due to other factors. However, focusing on the reduction in feed intake alone as a consequence of feeding Bovaer® could also have resulted in a missed opportunity to increase milk yield. In 2026, milk production increased by 1.8% and feed efficiency by 1.7%, while there was no change in DMI. While these changes may seem modest, milk production started at a very high level on 1 January 2026.
A sample of maize silage taken during the summer of 2026 showed a slightly elevated level of mycotoxin (DON). While the level was not sufficiently high to cause issues in the herd, it should be used as an indicator that maize harvested in 2025 may have mycotoxins that potentially can result in reduced production. There have been reports from other farmers in 2026 that they had experienced toxicity symptoms when feeding maize silage. Some farmers have analyzed for mycotoxins, whereas others have not.
Farmer takeaway: "Seeing the results on our own farm helped build confidence."
Key Results 2025
| Indicator | Results | Change During Bovaer® Use |
ECM, kg/cow day | 42.9 – 44.9 | +4.7% |
DMI, kg/cow day | 24.4 – 23.1 | -5.3% |
Feed Efficiency, kg/kg | 1.76 – 1.94 | +10.2% |
Key Results 2026
| Indicator | Results | Change During Bovaer® Use |
| ECM | 45.6 – 46.4 | +1.8% |
| DMI | 25.4 – 25.4 | 0% |
| Feed Efficiency | 1.80 – 1.83 | +1.7% |
This large farm provides one of the most extensive practical experiences with Bovaer® in Denmark.
The farm used Bovaer® continuously throughout 2025 and 2026, making it the longest-running example in this group of farms.
During this period, the product became a normal part of the feeding programme and the farmer remained satisfied with the experience. In 2026, the farmer contemplated stopping the use of Bovaer® after 80 days. This was partly due to the bureaucracy of claiming the subsidy and partly due to delayed payment of the subsidy in 2025. However, as milk yield continued to increase, the decision was to continue feeding Bovaer®.
In 2025, production records showed a 7% increase in ECM, alongside a 3-6% increase in feed intake and a 3.2% improvement in feed efficiency.
In 2026, production continued to increase with +4.1% in ECM, +3.4% in DMI and +0.6% in feed efficiency.
Throughout the period of using Bovaer®, the farmer had a stable feed ration with very small variations in crude protein, starch and NDF.
Farmer takeaway: "Our experience with the product remained positive. Administration was a bigger challenge than adoption."
Key Results 2025
| Indicator | Results | Change During Bovaer® Use |
| ECM | 38.8 – 41.5 | +7.0% |
| DMI | 25.2 – 26.1 | +3.6% |
| Feed Efficiency | 1.54 – 1.59 | +3.2% |
Key Results 2026 (January to July)
| Indicator | Results | Change During Bovaer® Use |
| ECM | 41.7 – 43.4 | +4.1% |
| DMI | 26.4 – 27.3 | +3.4% |
| Feed Efficiency | 1.58 – 1.59 | +0.6% |
This small Jersey herd began using Bovaer® throughout 2025 and continued from 1 January to 22 March 2026.
The farmer reported a positive overall experience and remained supportive of the programme. Production performance remained strong and no concerns were reported regarding animal health or herd management.
Among the five participating farms, this herd recorded the strongest production indicators. In 2025, ECM increased by 9.4%, feed intake by 6.6%, and feed efficiency improved by 0.6%. In 2026, ECM continued to increase by 1.9% and DMI by 6.3%, while feed efficiency decreased by 4.2%.
The farmer ultimately stopped using Bovaer® for the full year in 2026 due to delays and uncertainty surrounding support payments rather than concerns about the product itself.
Farmer takeaway: "The experience on farm was positive, and we would welcome greater certainty around programme support."
Key Results in 2025
| Indicator | Results | Change During Bovaer® Use |
| ECM | 36.1 – 38.6 | +9.4% |
| DMI | 22.8 – 24.3 | +6.6% |
| Feed Efficiency | 1.58 – 1.59 | +0.6% |
Key Results 2026 (January to March)
| Indicator | Results | Change During Bovaer® Use |
| ECM | 36.7 – 37.4 | +1.9% |
| DMI | 22.2 – 23.6 | +6.3% |
| Feed Efficiency | 1.65 – 1.58 | -4.2% |
This medium-large sized Holstein herd used Bovaer® during seasonal periods from 1 March to 20 May in both 2025 and 2026.
The farmer's experience highlights the importance of looking at the complete farm picture. During the monitoring period, feed-quality challenges linked to mycotoxins in maize silage in 2025 affected the herd and required careful investigation.
Despite these challenges, production remained stable to positive. In 2025, ECM increased by 1.2% and feed efficiency by 2.6%, while feed intake decreased by 1.5%. In 2026, ECM continued to increase by 2.1% and DMI by 2.8%, while feed efficiency decreased by 0.7%.
Like DK2, the farmer experienced a small drop in feed intake in 2025 whereas the ECM increased by 1.2% during the same period. This farmer operates in an area with a lot of grass and consequently uses less maize silage than the other farmers in this report.
The experience reinforced the importance of evaluating all potential factors affecting herd performance before drawing conclusions.
Farmer takeaway: "Looking at the complete farm picture is essential."
Key Results in 2025 (March to May)
| Indicator | Results | Change During Bovaer® Use |
| ECM | 41.5 – 42.0 | +1,2% |
| DMI | 27.1 – 26.7 | -1.5% |
| Feed Efficiency | 1.53 – 1.57 | +2.6% |
Key Results 2026 (March to May)
| Indicator | Results | Change During Bovaer® Use |
| ECM | 43.1 – 44.0 | +2.1% |
| DMI | 28.5 – 29.3 | +2.8% |
| Feed Efficiency | 1.51 – 1.50 | -0.7% |
No two farms are identical. Herd size, breed, feed strategy and management style all influence day-to-day results.
Yet across these five Danish farms, a common theme emerged during the first years of Bovaer® implementation in Denmark.
Farmers were able to incorporate Bovaer® into their feeding programmes without disrupting normal farm operations. They reported confidence in the product, saw their cows continue to perform as expected and observed no consistent pattern of negative animal-health outcomes.
Just as importantly, several farmers expressed their willingness to use Bovaer® again, demonstrating the confidence that comes from direct experience rather than speculation.
These experiences represent real Danish farms, real Danish farmers and real-world conditions. While every farm remains unique and these observations do not establish causation, they offer valuable insight into how Bovaer® can be used successfully in commercial dairy systems.
Introducing new solutions requires trust, partnership and ongoing support.
That is why we remain committed to standing alongside farmers throughout their Bovaer® journey. Together with VetSalus, dsm-firmenich has established a Rapid Response Team of veterinary and nutrition experts to support farmers and herd veterinarians when questions arise. Farmers are encouraged to contact their herd veterinarian first, who can involve the team when additional expertise or further investigation is needed.
Whether farmers are using Bovaer® today, considering its use in the future or simply have questions about implementation, we want them to have access to reliable information and practical support. We support Denmark’s climate ambitions, and we believe that confidence and trust are strongest when farmers choose to adopt solutions like Bovaer® voluntarily.
More information is available at Bovaer.dk.
