Bovaer Cattle Feed Trial Raises Concerns Amid Claims of Adverse Animal Health Effects in Denmark and UK Trials

Reports have surfaced of adverse cattle health incidents linked to the use of Bovaer, a methane-reducing feed additive promoted by major British retailers such as Tesco and Morrisons. Dozens of farmers, primarily in Denmark where Bovaer is being trialled extensively, have described problems including fever, stomach cramps, decreased milk production and, in some cases, death among their cows.

One Danish dairy farmer, Anders Ring, publicly reported that an animal became unwell and died after being dosed with Bovaer. Some of his cattle experienced foot infections and reduced output. Describing Bovaer as a poison, he stated that numerous farms had encountered collapsed cows and milk quality issues, prompting him to end participation in the trial after only a month.

The Danish Dairy Farmers Association has registered complaints from around 40 farmers, citing issues believed to be associated with the additive. The Danish Agriculture and Food Council for Cattle confirmed awareness of several cases of health complications subsequent to the start of Bovaer use, calling the reports a significant concern for the industry.

Bovaer functions by altering methane production during the digestive process in the cow’s rumen, the largest of the animal’s four stomach compartments. Methane emissions from cattle are a known contributor to global warming; the additive was designed to reduce these emissions and thus help the agricultural sector reach net zero targets. British supermarkets, including Aldi, applauded early trials as a scalable strategy for major emissions reductions. Both the UK Food Standards Agency and its EU counterpart have approved Bovaer as safe for livestock and consumers; nevertheless, the recent reports have prompted further scrutiny.

In Britain, Arla, the largest dairy producer, concluded its own trials of Bovaer and is currently reviewing the findings. The UK Food Standards Agency is closely monitoring developments and assessing potential implications for domestic dairy farmers.

James Runciman, a cattle farmer from Norfolk, expressed caution, arguing that the digestive ecosystem of cows is highly complex and not easily modified without risk. He noted that farmers required protective equipment to handle the supplement and cited widespread reports of health issues.

DSM-Firmenich, the Dutch multinational responsible for Bovaer’s production, maintains that the additive is safe, referencing over 15 years of research with no proven pattern of negative health outcomes in cattle. The company is cooperating with Danish authorities, who, alongside Aarhus University, have launched an official inquiry into the incidents. DSM-Firmenich has encouraged all parties to await the outcome of this investigation before forming definitive judgements.

Norway’s government had recently mandated Bovaer’s inclusion in all dairy cattle feed from 2027 as part of a national climate initiative. The state-supported dairy cooperative Tine, which holds a monopoly in Norway, has paused the additive’s rollout pending results from ongoing evaluations.

The case has underscored the complexity of balancing environmental objectives with animal welfare and farm productivity. As reviews and investigations continue, the future of Bovaer in European dairy farming remains unresolved.