Bovaer is a feed additive developed by the Swiss-Dutch company DSM-Firmenich. Its active ingredient, 3-nitrooxypropanol (3-NOP), works by suppressing a specific enzyme in a cow's rumen (the first stomach compartment) that produces methane during digestion. This reduces methane emissions from dairy cows by about 27-30% and from beef cattle by up to 45%. Methane is a potent greenhouse gas, and livestock farming contributes significantly to global emissions, which is why Bovaer is promoted as a tool for climate mitigation. The additive breaks down naturally in the cow's digestive system into compounds already present in the rumen, and regulators confirm it leaves no residues in milk, meat, or manure, making it safe for human consumption. It has been approved by authorities in over 68 countries, including the EU's European Food Safety Authority (EFSA), the UK's Food Standards Agency (FSA), and the Danish Veterinary and Food Administration, based on over 150 peer-reviewed studies.
Bovaer is typically mixed into feed at low doses (about 60-80 mg per kg of dry matter) and has been in commercial use since around 2021. It's not a drug but a supplement, often compared to other feed additives like vitamins or minerals. However, some studies have noted potential side effects in cows at recommended doses, such as reduced feed intake, which could indicate discomfort or welfare issues.
### The Danish Policy and Mandate
Denmark, a major dairy producer, has aggressive climate goals under its Green Tripartite Agreement, aiming to cut agricultural greenhouse gas emissions by 55-65% by 2030. As part of this, starting January 1, 2025, all non-organic dairy farms with more than 50 cows must incorporate methane-reducing measures into their feeding routines. Farmers have two main options:
- Feed cows a high-fat diet (at least 48g of fatty acids per kg of dry matter) year-round, which can reduce methane by altering digestion.
- Use a 3-NOP additive like Bovaer for at least 80 days per year.
The government provides subsidies to cover costs (e.g., around 1,000 DKK per cow annually), with extra incentives for exceeding the minimum. Failure to comply can result in fines or loss of subsidies. Bovaer is currently the primary approved additive in Denmark, though the policy allows equivalents if they meet standards. This mandate applies only to larger conventional farms; organic farms are exempt.
The policy stems from Denmark's broader push for sustainable agriculture, including breeding low-emission cows and other innovations. Arla Foods, a major Danish-Swedish dairy cooperative, has been involved in piloting Bovaer and supports the initiative, though it's farmer-owned and profits go back to members.
### The "Scandal" and Claims of Harm
The so-called "Bovaer scandal" in Denmark refers to widespread social media and anecdotal reports emerging around October-November 2025 claiming that the additive is causing severe health issues in cows, including:
- Sudden collapses, high fevers (up to 40°C), diarrhea, mastitis (udder inflammation), reduced milk production, and refusal to eat treated feed.
- Deaths, with some unverified claims of "thousands" of cows dying or being euthanized.
- Farmers reportedly noticing quick recovery when they stop using Bovaer and switch back to normal feed.
These claims gained traction on platforms like X (formerly Twitter) and Facebook, with posts from farmers and commentators alleging the mandate is an "uncontrolled experiment" forcing toxic chemicals on healthy animals. For example:
- One farmer reportedly lost 6 cows in a month.
- Others describe it as similar to past chemical scandals like DDT or Teflon, arguing it's unnecessary for "raske dyr" (healthy animals) and driven by climate ideology rather than science.
Critics tie this to broader conspiracy narratives, falsely claiming involvement by Bill Gates (he's not; DSM-Firmenich owns it fully, with major investors like BlackRock and Vanguard). Some argue it's part of a "depopulation" agenda or an attack on traditional farming, leading to calls for boycotts of Danish dairy products like Arla's Lurpak butter or Cravendale milk. These reports intensified after the mandate's implementation, with some sources misstating the start date as October 1, 2025, instead of January.
Similar concerns have echoed in neighboring countries like Norway, where farmers report comparable issues and resist mandates set for 2027.
### Counterarguments and Official Stance
Official sources and the manufacturer strongly refute widespread harm, labeling much of the outcry as misinformation similar to earlier UK boycotts in late 2024. Key points:
- **Safety for Cows:** Regulators like EFSA conclude Bovaer is safe at approved doses, with no established margin of safety issues in most studies, though genotoxicity (potential DNA damage) wasn't fully ruled out in early reviews. High-dose animal trials (e.g., in rats) showed risks like fertility damage or tumors, but these are irrelevant to cow dosing.
- **No Official Death Reports:** There are no confirmed official reports from Danish authorities linking Bovaer to mass cow deaths as of November 2025. Claims appear anecdotal, with no peer-reviewed evidence of widespread fatalities. Factors like seasonal illnesses, poor feed mixing, or unrelated farm issues could explain symptoms.
- **Ongoing Investigations:** Aarhus University launched a 2025-2028 project to specifically examine Bovaer's welfare impacts, including behavior, comfort, and feed preferences, after prior studies noted reduced intake. This is the first dedicated welfare study, acknowledging potential gaps.
- **Broader Context:** Proponents argue methane from cows is part of a natural carbon cycle, but industrial farming amplifies it. Critics say the mandate ignores root causes like monoculture or over-concentration of livestock, prioritizing quick fixes for political targets.
The Danish minister has rejected calls for warning labels on milk, citing no evidence of harm. DSM-Firmenich emphasizes two years of safe use globally without issues.
### Why the Controversy Persists
This "scandal" mirrors global debates on climate policies vs. farming realities. Farmers feel burdened by mandates that could hurt livelihoods if cows produce less milk or require euthanasia. Social media amplifies unverified stories, fueling boycotts and distrust, while officials point to rigorous testing. If welfare concerns are validated by the Aarhus study, it could lead to policy changes; otherwise, it may be dismissed as misinformation. For now, it's a flashpoint in the tension between environmental goals and animal agriculture. If you're a consumer, opting for organic Danish dairy avoids the additive entirely.