3-NOP (Bovaer™) Receives FDA Approval

Dr. Kirby Krogstad, Assistant Professor, Department of Animal Sciences, The Ohio State University

The News!     

This week, on May 28th, the Food and Drug Administration announced that Bovaer met their safety and efficacy requirements. Bovaer is the commercial name for 3-Nitrooxypropanol (3-NOP) which is a potent methane mitigator that can now be fed to lactating dairy cattle to reduce enteric methane emissions. The product is being marketed in North America by Elanco and dsm-firmenich. Bovaer is also expected to have an associated carbon credit that will be paid to cooperating farmers.

How Effective is 3-NOP at Reducing Methane?

Feeding 3-NOP to lactating dairy cattle reduces enteric methane emissions by approximately 30% (Figure 1). Two independent meta-analyses concur with this finding.

  1. A recent meta-analysis conducted at Pennsylvania State University observed that 3-NOP reduces enteric methane emissions by 123 g/day or 28%. They also observed that 3-NOP did not affect feed intake or fluid milk yield. Interestingly, they observed that 3-NOP tends to increase milk fat yield by 90 g/day. Read the entire meta-analysis here: https://doi.org/10.3168/jds.2021-21398.
  2. The other meta-analysis from UC-Davis observed a 33% reduction in enteric methane emissions. What these authors observed was that the efficacy of 3-NOP was reduced as the concentration of fiber in the diet was increased. Also, reducing dietary fat increased the efficacy of 3-NOP. Read the details from this meta-analysis here: https://doi.org/10.3168/jds.2022-22211 mented with 3-NOP.

 Figure 1. The observed reduction in enteric methane emissions from lactating dairy cattle supplemented with 3-NOP.

Long-term feeding of 3-NOP?

One limitation of the data with methane mitigants like 3-NOP is how long-term feeding, like feeding it for a whole lactation, effects milk production of dairy cows. Currently, one experiment from Europe supplemented 3-NOP to cows for an entire lactation. They observed that methane production was reduced by 21% without affecting dry matter intake. Interestingly, they observed a 6.5% increase in energy-corrected milk yield from cows supplemented with 3-NOP. The entire study can be reviewed here: https://www.journalofdairyscience.org/article/S0022-0302(24)00500-9/fulltext. More full-lactation experiments under conditions mirroring United States production systems are necessary to build confidence in the response observed in this investigation.

Will it Pay?

Using our Dairy Carbon Return Calculator, I investigated the breakeven cost of 3-NOP. I made the following assumptions:

  1. Carbon price of $30/ton
  2. Milk price of $17.50/cwt
  3. Ration cost of $0.15/lb DM

In the first scenario, I assumed that a farm could expect the average changes in milk production (+3%) and feed intake (+1.6%) when 3-NOP is fed. Under this scenario, the breakeven cost for feeding 3-NOP is $0.41 to 0.45/hd/day. If I assume no change in milk production or feed intake, the breakeven cost of feeding 3-NOP is $0.10 to 0.14/hd/day. These estimates will continue to change based on the carbon markets and any potential regulations for carbon markets. Also, the return on investment for these feeding strategies may depend on where your milk is going, what its used for, or who is using it.


The approval of a feed additive for methane mitigation is a watershed moment – it’s the first of its kind. Surely, there will be more to follow. 3-NOP reliably reduces enteric methane production, but it must be economically viable for a farm. If you’re considering 3-NOP for your farm, or your client’s dairy farm, use our Dairy Carbon Return Calculator or other tools to determine if it is a good fit.