Bovaer and Danish Cattle Farms: Key Insights

The Debate Over Bovaer and Methane Reduction in Danish Cattle

Danish farmers have recently raised concerns about the health of their herds, following a mandate to reduce methane emissions through dietary changes. These concerns have been amplified by social media posts featuring videos that claim the feed additive Bovaer is causing cows to collapse and die. While regulatory agencies in Denmark have launched an investigation, there is currently no evidence that the compound causes cattle deaths.

A post on X from November 4, 2025, claimed that "Denmark forces farmers to give a chemical to cows to stop them from farting, for climate! Now cows in Denmark are collapsing and dying due to Bovaer poisoning." This message gained traction online, with some unrelated accounts resharing it across different platforms and languages. Climate-skeptic accounts also helped spread these claims.

The videos reference a 2025 Danish mandate aimed at curbing emissions from the meat and dairy industry. Farmers are required to either add more fat to cows’ diets or administer the compound Bovaer. The latter option is seen as more convenient for many farmers.

Bovaer, produced by the Swiss-Dutch company DSM-Firmenich, uses the active ingredient 3-nitrooxypropanol (3NOP) to alter the last stage of a cow’s digestion, turning its burps into hydrogen rather than methane. Methane is a potent greenhouse gas that contributes significantly to global warming.

Despite these concerns, government and industry experts are still investigating whether the reported health issues in cows are linked to Bovaer. Importantly, no country currently mandates the use of Bovaer.

Understanding the Danish Regulation

Ermias Kebreab, associate dean for global engagement in the College of Agricultural and Environmental Sciences at the University of California, Davis, noted that while farmers can choose between adding fat to the diet or using Bovaer, the latter is much easier to implement.

Kebreab told AFP on November 21 that Bovaer is a well-researched additive with over 100 published papers, and extensive scientific evidence shows no significant negative impacts on cattle health when 3NOP is integrated into their diet.

The Danish Veterinary and Food Administration stated in a November 22 press release that it is monitoring the situation with its industry partners and may adjust the feed models suggested for 2026. Farmers are encouraged to report any health issues to the government.

SEGES Innovation, the Danish research and development firm investigating the complaints, reported that out of 644 milk-supplying herds taking the additive, 419 showed a decline in feed consumption, 434 recorded a drop in milk production, and 376 reported both issues.

Lars Arne Hjort Nielsen, senior specialist in cattle production at SEGES Innovation, emphasized the importance of mixing Bovaer thoroughly and evenly in the feed ration to avoid overdosing and ensure effectiveness.

Global Use and Scientific Consensus

Bovaer is authorized for use in 70 countries, including Canada and the United States, according to DSM-Firmenich. The company reported that no other countries have reported issues with the additive.

A spokesperson for DSM-Firmenich told AFP on November 27 that Bovaer was successfully used in the first nine months of the year in Denmark by 400 dairy farmers without being identified as a contributor to health issues in cows.

Some studies have reported reduced feed intake and lower milk production in cows consuming Bovaer. Charles Nicholson of Pennsylvania State University, who reported such effects in his research, said the changes observed do not seem large enough to reflect or result in other health issues for the average cow.

Luiz Ferraretto, a ruminant nutrition associate professor at the University of Wisconsin-Madison, noted that 3NOP has been tested extensively worldwide, and no concerns about major reductions in dairy cow productivity or health were raised.

A separate study, funded by DSM-Firmenich and the regional economic development branch of the Northern Netherlands Alliance, reported an increase in milk production. Jan Dijkstra, associate professor in ruminant nutrition at Wageningen University, stated that current scientific literature does not provide any indication or mechanism on how 3NOP may cause problems like mastitis, dermatitis, or death.

Regulatory Approval and Safety

DSM-Firmenich stated that the UK Food Standards Agency and the European Food Safety Authority (EFSA) approved the additive based on evidence that it does not harm animals or negatively impact their health, productivity, or milk quality.

The EFSA referred AFP to its 2021 scientific opinion, formed by an expert panel on additives per the European Commission's request. An EFSA spokesperson told AFP on November 26 that the experts concluded Bovaer 10 is safe for dairy cows at the maximum recommended level, with no safety concerns for consumers or the environment.

Previous unsupported claims alleged Bovaer was linked to health issues in humans, but these have not been substantiated.

Sector Transition and Climate Impact

Ruminant livestock, particularly cattle, are a key focus in mitigating emissions from human activities. Katharine Dickson, a biomethane scientist at the University of California, Davis, noted that most of agriculture’s methane problem rests on the back of the cattle sector.

Using Bovaer to reduce methane and curb emissions provides an “industry preserving” strategy that is more easily adopted than previous approaches to feed manipulation, she said on November 25.

In contrast, Dickson said mandating people to cut meat consumption is “extremely unlikely to be viable in a democracy with strong consumer preferences and a largely market-based food system.”