The methane-reducing feed additive Bovaer is “very close” to being used on farms in Ireland, Laurence Shalloo of Teagasc Moorepark has said.

He told a Teagasc Signpost webinar on Friday that Bovaer would first be used in a dry cow diet.

If the sector is to hit its climate targets, feed additives will have to be in a significant proportion of dairy and beef animal diets by 2030.

Standout additives in terms of methane reduction potential are asparagopsis and 3-NOP (Bovaer).

Asparagopsis is a red seaweed, which grows best in warm water and is now being grown in tanks around Europe.

Bovaer was approved for use in the EU in 2022, but only for the dairy herd.

There are over 50 papers published to date, which report reductions in methane of about 30%.

The challenge researchers are facing is finding an additive that is compatible with grazing systems, as most studies done to date have been carried out in indoor systems and where the additive has been part of a total mixed ration (TMR).

The additive works by binding to an enzyme in the rumen, preventing methanogenic bacteria from binding to carbon dioxide and hydrogen and stopping the formation of methane, and is fed based on kilo of dry matter intake (80mg of Bovaer per kilo of dry matter).

Pilot project

Hazel Costigan, a researcher at Teagasc, outlined a study carried out by Teagasc which saw 3,500 cows on 18 farms fed Bovaer over an eight-week period.

Cows were fed twice daily on exit from the parlour. They were given 6.8g per milking (13.6g/day), which was mixed with 500g of a coarse ration. This pilot project resulted in a 3.3% annual reduction of methane.

Use of the additive was recognised and included in the carbon footprint of the farms involved.

The cost was €13.50 to €15 per cow to carry out the study. Farmers noted that use is not labour intensive and there is little additional work involved, as it can be mixed in with dry cow mineral or TMR.

Short-term reduction

While researchers see a 30% reduction in methane for up to three hours post consumption, after this period, methane production reverts back, meaning that over the course of the day, methane reduction averages at 6%, Costigan said.

Bovaer is not suitable in an organic system, but it is expected that asparagopsis will be less of an issue due to its natural origin.

Who pays?

It remains to be seen how or if these feed additives will be incentivised. Shalloo questioned whether feed additives would be funded from CAP, market support or direct consumer support.

However, in order for this technology to play a part in reducing emissions, Shalloo said that it must be recognised and accounted for in Ireland’s national greenhouse gas emissions inventory.

Other measures

Other ways in which farmers can reduce methane emissions on their farms are:

  • Grazing management – utilising spring grass, grazing at covers of 1,500kg/DM/ha.
  • Reducing age of slaughter in beef animals.