Paul Crosson, Animal and Grassland Research and Innovation Centre, Teagasc, Grange

Genetic improvement is a proven technology to advance animal performance in key traits such as liveweight gain and fertility, thereby improving farm profitability and reducing greenhouse gas emissions.

Currently, suckler beef breeding indexes in Ireland assess animal performance on the basis of the impact of changes in performance traits on economics.

Given the demands of food production systems, and thus beef cattle production, to reduce greenhouse gas emissions, a Teagasc/ICBF project team was established in 2022 to augment the existing suckler beef breeding indexes.

A multispecies sward. / Donal O' Leary

Its brief was to assess the impact of each unit change in performance traits on greenhouse gas emissions.

The analysis was completed using the Teagasc beef systems model with performance measured in units of carbon dioxide equivalents.

Measuring methane emissions in dairy cows using the GreenFeed system in Moorepark, Co Cork. / Donal O' Leary

To take one example, this analysis showed that each day reduction in age at first calving reduced greenhouse gas emissions by 1.4kg carbon dioxide equivalents, predominantly due to lower emissions from ruminant digestion and less feed production emissions.

The carbon dioxide equivalent units were then expressed in financial terms by using a carbon price of €80/t (based on the typical value of carbon traded on carbon markets) so the above value for age at first calving was €0.11/day.

Production economic value

The ‘carbon’ value was combined with the ‘production economics’ value to generate a composite measure.

Tillage radish, mustard and phacelia growing as a catch crop.

Again, using the above example of age at first calving, the production economic value calculated was €1.76 per day so the composite value for this trait was €1.87/day.

This exercise was repeated for each of the traits in the suckler beef breeding indexes.

The updated breeding indexes, which also included an update of the existing economic values based on price changes and the addition of new traits such as age at finishing, were launched recently by ICBF.