The report states that contributing to the 67% increase in milk production over the period were higher yields per cow, which spread emissions from each dairy cow over a greater production volume.

Overall, GHG emission intensities on farms in the report ranged from 0.91kg to 2.06kg of CO2e/kg ECM (excluding sequestration) with an average value of 1.32.

The range in emission intensities across dairy farms was mostly put down to variations in yield per cow and also the proportion of livestock on farms that were lactating.

In particular, as the number of dairy replacements increases on a farm, so does their associated costs and emissions have to be spread over the milk produced. This highlights the importance of minimising replacement rates and meeting target calving ages.

Sources

The three largest contributing sources to GHG emission from dairy are methane from enteric fermentation emissions (42%), manure emissions (20%) and concentrates production/transport emissions (15%).

The UK Climate Change Act commits the UK to an 80% reduction in GHG emissions by 2050 from 1990 baseline levels.

In terms of total GHG emissions, the wider NI farming industry reduced total emissions by 5.2% since 1990 and, overall in NI, emissions decreased by 17.4% over the period.

A Government consultation document last year stated that in 2013 agriculture accounted for 29% of GHG emissions in NI, making the industry the largest source of emissions.

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Industry must spread the efficiency message

Listen: genetics of feed efficiency and methane emissions