Animal breeding in its simplest term is identifying the favourite animals as parents of the next generation; while favourite can mean lots of different things to different people, it generally boils down to productive and healthy animals.
The Irish dairy cow today is 14% more carbon-efficient than it was 20 years ago due to breeding.
Ireland is also heavily investing in the large-scale measurement of methane emissions from individual dairy and beef cattle, as well as sheep. The end goal is to identify low-emitting animals which, themselves will become parents of the next generation, cumulatively reducing the quantity of methane emitted as a whole.
Research is ongoing in Teagasc to develop farm-ready technologies to reduce methane emissions from ruminants including feed supplements. A promising feed additive, 3-NOP, has proved to be an effective feed additive to mitigate enteric CH4 emissions without compromising animal performance with methane yield decreases in the range of 30%. However, it is not yet registered for use in the EU.
As Ireland is largely pasture-based and feed additives need to be fed continuously, issues arise around delivery during grazing. Slow release options will have to be developed or indeed early-life supplementation strategies may be more appropriate for pasture-based delivery.
Reducing nitrous oxide from fertilisers
Nitrogen fertiliser application to Irish grassland soils releases nitrous oxide (N2O) emissions, accounting for approximately 10% of national agricultural emissions.
Approximately 50% of nitrogen fertiliser is applied as straight nitrogen fertiliser and the remainder is applied as N-P-K compounds.
Switching straight nitrogen from CAN to protected urea reduces emissions by 80% by reducing soil nitrate. Similarly, switching compound fertilisers to low nitrate compounds could also reduce emissions.
Recently published research found that high nitrate compound fertilisers (27-2.5-5) emissions are 31% to 44% higher than low nitrate fertilisers (18:6:12). This research is being expanded to evaluate the effect of compound fertiliser formulation across multiple sites and years.
Evaluation of multispecies grassland systems
Legume-based multispecies grassland mixtures can maximise the use of symbiotically fixed nitrogen, and displace inorganic N fertiliser, while reducing GHG emissions and nitrate leaching, and increasing carbon sequestration in grassland based systems.
In an EU-scale experiment, four-species mixtures (two grasses and two legumes) consistently yielded better than the average of the four monocultures, and even yielded more than the best-performing monoculture in the majority of cases (Finn et al, 2013).
The inclusion of herbs can also bring extra yield and more complete feeding value, especially of minerals and bioactive secondary metabolites.
Compared to monocultures, plant richness also enhances grassland yield stability over seasons and weather disturbances.
Currently, long-term, system-scale grazing experiments comparing simple and diverse swards on the performance of grazing dairy and beef cattle are under way at Johnstown Castle, Moorepark and Grange research centres.
On-farm white
clover cultivar study
In 2021, Teagasc Moorepark commenced an on-farm white clover project with the aim of establishing white clover on 35 grassland farms (dairy, beef and sheep) across the country. This project will aim to establish white clover on farms over a four-year period, with between 20% and 30% of the area sown with clover per year.
The overall aim is for farms to be in a position to reduce chemical fertiliser when adequate sward clover contents (approximately 20%) have been achieved.
The project has just completed its first year, with very successful clover establishment to date.
There is increasing focus on age at slaughter as a trait, given its association with greenhouse gas emissions. Yearling beef cattle produce approximately 200g of methane per day and, therefore, there are opportunities to reduce methane emissions from a beef animal by advancing slaughter age so that the number of days producing methane is reduced.
There are also potential greenhouse gas emissions reductions from lower feed demand, less manure and a reduction in other activities associated with cattle production.
At present, research at Grange is exploring the optimum point of slaughter given the overall effects on the lifetime output of methane gas and other greenhouse gases related to cattle production.
National Agricultural Soil
Carbon Observatory
Teagasc has established the National Agricultural Soil Carbon Observatory to provide the knowledge required on soil carbon sequestration. Deep soil samples will be taken on the Signpost farms to establish baseline soil carbon levels, with the sampling process repeated in a number of years’ time to monitor any changes.
In addition, flux data from long-term eddy covariance towers will provide detailed information on carbon exchange at an eco-system level.
It is also envisaged that a LiDAR survey will be undertaken on Signpost farms at the start and end of the programme so that C sequestration in hedgerows can be quantified.
Methane research in grazing systems
New research is assessing the impact of selecting cows using the economic breeding index (EBI) on methane production as well as the total amount of methane produced by dairy cows across a full grazing season.
This is the first research in Ireland to measure methane across the main part of the grazing season. It is anticipated that this research will improve the accuracy of baseline methane values for Irish grazing dairy cows. This data will be compared to the Irish national GHG inventory model outputs.
Future research will aim to quantify the impact of variations in pasture quality, mass, and availability, as well as the influence of clover and multispecies swards on methane.
Animal breeding in its simplest term is identifying the favourite animals as parents of the next generation; while favourite can mean lots of different things to different people, it generally boils down to productive and healthy animals.
The Irish dairy cow today is 14% more carbon-efficient than it was 20 years ago due to breeding.
Ireland is also heavily investing in the large-scale measurement of methane emissions from individual dairy and beef cattle, as well as sheep. The end goal is to identify low-emitting animals which, themselves will become parents of the next generation, cumulatively reducing the quantity of methane emitted as a whole.
Research is ongoing in Teagasc to develop farm-ready technologies to reduce methane emissions from ruminants including feed supplements. A promising feed additive, 3-NOP, has proved to be an effective feed additive to mitigate enteric CH4 emissions without compromising animal performance with methane yield decreases in the range of 30%. However, it is not yet registered for use in the EU.
As Ireland is largely pasture-based and feed additives need to be fed continuously, issues arise around delivery during grazing. Slow release options will have to be developed or indeed early-life supplementation strategies may be more appropriate for pasture-based delivery.
Reducing nitrous oxide from fertilisers
Nitrogen fertiliser application to Irish grassland soils releases nitrous oxide (N2O) emissions, accounting for approximately 10% of national agricultural emissions.
Approximately 50% of nitrogen fertiliser is applied as straight nitrogen fertiliser and the remainder is applied as N-P-K compounds.
Switching straight nitrogen from CAN to protected urea reduces emissions by 80% by reducing soil nitrate. Similarly, switching compound fertilisers to low nitrate compounds could also reduce emissions.
Recently published research found that high nitrate compound fertilisers (27-2.5-5) emissions are 31% to 44% higher than low nitrate fertilisers (18:6:12). This research is being expanded to evaluate the effect of compound fertiliser formulation across multiple sites and years.
Evaluation of multispecies grassland systems
Legume-based multispecies grassland mixtures can maximise the use of symbiotically fixed nitrogen, and displace inorganic N fertiliser, while reducing GHG emissions and nitrate leaching, and increasing carbon sequestration in grassland based systems.
In an EU-scale experiment, four-species mixtures (two grasses and two legumes) consistently yielded better than the average of the four monocultures, and even yielded more than the best-performing monoculture in the majority of cases (Finn et al, 2013).
The inclusion of herbs can also bring extra yield and more complete feeding value, especially of minerals and bioactive secondary metabolites.
Compared to monocultures, plant richness also enhances grassland yield stability over seasons and weather disturbances.
Currently, long-term, system-scale grazing experiments comparing simple and diverse swards on the performance of grazing dairy and beef cattle are under way at Johnstown Castle, Moorepark and Grange research centres.
On-farm white
clover cultivar study
In 2021, Teagasc Moorepark commenced an on-farm white clover project with the aim of establishing white clover on 35 grassland farms (dairy, beef and sheep) across the country. This project will aim to establish white clover on farms over a four-year period, with between 20% and 30% of the area sown with clover per year.
The overall aim is for farms to be in a position to reduce chemical fertiliser when adequate sward clover contents (approximately 20%) have been achieved.
The project has just completed its first year, with very successful clover establishment to date.
There is increasing focus on age at slaughter as a trait, given its association with greenhouse gas emissions. Yearling beef cattle produce approximately 200g of methane per day and, therefore, there are opportunities to reduce methane emissions from a beef animal by advancing slaughter age so that the number of days producing methane is reduced.
There are also potential greenhouse gas emissions reductions from lower feed demand, less manure and a reduction in other activities associated with cattle production.
At present, research at Grange is exploring the optimum point of slaughter given the overall effects on the lifetime output of methane gas and other greenhouse gases related to cattle production.
National Agricultural Soil
Carbon Observatory
Teagasc has established the National Agricultural Soil Carbon Observatory to provide the knowledge required on soil carbon sequestration. Deep soil samples will be taken on the Signpost farms to establish baseline soil carbon levels, with the sampling process repeated in a number of years’ time to monitor any changes.
In addition, flux data from long-term eddy covariance towers will provide detailed information on carbon exchange at an eco-system level.
It is also envisaged that a LiDAR survey will be undertaken on Signpost farms at the start and end of the programme so that C sequestration in hedgerows can be quantified.
Methane research in grazing systems
New research is assessing the impact of selecting cows using the economic breeding index (EBI) on methane production as well as the total amount of methane produced by dairy cows across a full grazing season.
This is the first research in Ireland to measure methane across the main part of the grazing season. It is anticipated that this research will improve the accuracy of baseline methane values for Irish grazing dairy cows. This data will be compared to the Irish national GHG inventory model outputs.
Future research will aim to quantify the impact of variations in pasture quality, mass, and availability, as well as the influence of clover and multispecies swards on methane.
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