Reducing greenhouse gas emissions and environmentally sustainable practices within livestock farming were central themes during AFBI’s “Farming for the future” open days last week.
Held at AFBI’s Hillsborough research unit over two days, the second day focused on beef and sheep systems in NI.
Researchers outlined some of the studies currently in progress which should deliver positive outcomes for commercial livestock farms as agri-policies shift towards net zero emissions.
At the same time, a lot of the messages relayed to farmers have been in the spotlight for decades, reiterating the importance of carrying out the basics of farming to the highest possible standards.
Topics like genetics and suckler cow fertility are nothing new, as is the importance of soil health, good grassland management and high quality forage.
Challenge
Setting the scene for the event, Professor Elizabeth Magowan said agriculture has a responsibility to improve air quality with 98% of ammonia emissions derived from livestock farming.
“The nitrogen element of ammonia is normally re-deposited within a 6km to 7km radius of its source, and, this impacts the bio-diversity balance within some environmentally sensitive areas.
“We have the potential to reduce ammonia emissions by 21%. Cutting nitrogen in cattle diets, reducing days to slaughter, multispecies swards and low emission slurry spreading can help deliver that reduction.”
Magowan also detailed the importance of reducing phosphorous (P) use to improve water quality, as NI farms have a P surplus of 11kg to 12kg/ha, more than twice the target figure of 5kg/ha.
Healthy soils are integral to profitable farming and improving aspects like fertility, organic matter and aeration are within the control of the farmer.
Soil health is comprised of three elements, starting with the chemical aspect such as nutrient availability and pH.
Physical elements include soil structure, while soil biology reflects the level of organisms present. When assessing soil health, speakers stated regular worm counts is a good starting point. Digging multiple soil cores measuring 20cm wide by 20cm deep will give an immediate snapshot of soil biology throughout the year.
Healthy soils will have worm counts greater than 20 within the sample core. For worm counts between 10 and 19, the advice was to review how land is being managed.
Greater use of organic manures and alleviating compaction can quickly increase worm activity.
Counts below 10 indicate poor quality soils in need of serious changes to soil management and farming methods.
Speakers stated the use of multispecies swards, with deeper rooting plants and the use of nitrogen fixing legumes, can increase worm populations by 30% over perennial ryegrass swards.
Resilient grassland management
Climate change is having an effect on grass growth and utilisation from season to season, something which was evident last year.
In 2023, 51% of the annual rainfall was recorded in May and June, rising to 152% from July to October.
Modelling of weather patterns, and grass growth over the next 75 years, shows increased yields in spring and autumn, with static growth in summer months.
“This will inevitably create huge challenges to utilise grass in the shoulders of the year,” said AFBI’s Naomi Rutherford.
Quoting figures from beef and sheep farms in the GrassCheck programme, there is a differential of 4.8t/ha in grass dry matter utilised. For every additional tonne of grass dry matter utilised, it generated £204 in profit.
Based on results from red clover silage and white clover grazing on two 10ha blocks, there was an 8t reduction in chemical fertiliser leading to a cost saving of £2,640, compared to ryegrass only swards.
“There was also an extra 2t DM/ha with the red clover silage swards over ryegrass swards that received 270kg/ha of nitrogen. Emissions were also lower” said Rutherford.
“Multispecies swards delivered higher liveweight gain in grazing trails with a 17% increase in young cattle compared to animals on ryegrass swards. They also have the added benefit of a more even grown curve through the summer months, helping to avoid a grazing deficit in July and early August.”
Feeding for 24-month-old
finishing systems
The average slaughter age of cattle destined for beef in Northern Ireland is 28 months. Just one third are finished at 24 months of age, or younger.
According to AFBI’s Francis Lively, reducing slaughter age to 24 months will reduce methane emissions by 17%.
“The start point to reduce slaughter age is forage. Feeding a high energy forage year round is crucial to drive weight gain.
“Cattle have a maintenance energy requirement. Once that energy demand is met, any surplus is directed to weight gain. The more high quality forage you can get into cattle, the higher the weight gain will be.
“It is possible to condense that energy intake with meal. But concentrate is ultimately an imported feed and increases the amount of phosphorous (P) on farms.
“Increased P creates water quality problems that farming has to address. So the more we can do with grass, the better,” said Lively.
Outlining weight gain targets, spring born suckler calves should be gaining 1.2kg/day from birth until weaning.
Over the first winter, weight gain should be in the region of 0.6kg/day, rising to 0.9kg/day during the second grazing.
“Well-managed, spring-born suckler-bred animals should be in the region of 550kg to 570kg at the end of the second grazing season.
“That allows an intensive 100 to 120 day finishing period to get animals into the 700kg territory and produce a 380kg to 400kg carcase.
“Good quality silage is crucial to weight gain in the shed. Weather can go against you when cutting, but if you set out to make high quality forage, there is the chance you will get the silage you want.”
Options for reducing ammonia
Trials looking at ammonia emissions from livestock were detailed to farmers with the outcomes from two farming scenarios presented.
The first trial looked at a dairy beef system finishing steers at 24 months of age with a 192 day grazing season.
Two thirds of slurry is stored in underground tanks and the remaining third being farmyard manure. Slurry is spread by splash plate and a mix of urea along with CAN is spread to drive grass growth.
The second option is a suckler cow to weaning system on LFA land with 100% slatted storage for slurry and no chemical fertiliser applied.
A combination of low emission slurry spreading (LESS), fitting mats in slatted sheds, extending grazing by two weeks, protected urea and regularly scraping slurry were employed to manage emissions.
In the dairy beef system, ammonia emissions were reduced by 34% through a combination of all five practices, rising to 42% in the LFA scenario.
Using LESS equipment was the single biggest factor to reduce ammonia in both trials and was advised as the best starting point for livestock farmers going forward.
Read more
Friesian cattle account for 30% of cattle kill in 2023
Tullamore Farm suckler and sheep open day launched
Reducing greenhouse gas emissions and environmentally sustainable practices within livestock farming were central themes during AFBI’s “Farming for the future” open days last week.
Held at AFBI’s Hillsborough research unit over two days, the second day focused on beef and sheep systems in NI.
Researchers outlined some of the studies currently in progress which should deliver positive outcomes for commercial livestock farms as agri-policies shift towards net zero emissions.
At the same time, a lot of the messages relayed to farmers have been in the spotlight for decades, reiterating the importance of carrying out the basics of farming to the highest possible standards.
Topics like genetics and suckler cow fertility are nothing new, as is the importance of soil health, good grassland management and high quality forage.
Challenge
Setting the scene for the event, Professor Elizabeth Magowan said agriculture has a responsibility to improve air quality with 98% of ammonia emissions derived from livestock farming.
“The nitrogen element of ammonia is normally re-deposited within a 6km to 7km radius of its source, and, this impacts the bio-diversity balance within some environmentally sensitive areas.
“We have the potential to reduce ammonia emissions by 21%. Cutting nitrogen in cattle diets, reducing days to slaughter, multispecies swards and low emission slurry spreading can help deliver that reduction.”
Magowan also detailed the importance of reducing phosphorous (P) use to improve water quality, as NI farms have a P surplus of 11kg to 12kg/ha, more than twice the target figure of 5kg/ha.
Healthy soils are integral to profitable farming and improving aspects like fertility, organic matter and aeration are within the control of the farmer.
Soil health is comprised of three elements, starting with the chemical aspect such as nutrient availability and pH.
Physical elements include soil structure, while soil biology reflects the level of organisms present. When assessing soil health, speakers stated regular worm counts is a good starting point. Digging multiple soil cores measuring 20cm wide by 20cm deep will give an immediate snapshot of soil biology throughout the year.
Healthy soils will have worm counts greater than 20 within the sample core. For worm counts between 10 and 19, the advice was to review how land is being managed.
Greater use of organic manures and alleviating compaction can quickly increase worm activity.
Counts below 10 indicate poor quality soils in need of serious changes to soil management and farming methods.
Speakers stated the use of multispecies swards, with deeper rooting plants and the use of nitrogen fixing legumes, can increase worm populations by 30% over perennial ryegrass swards.
Resilient grassland management
Climate change is having an effect on grass growth and utilisation from season to season, something which was evident last year.
In 2023, 51% of the annual rainfall was recorded in May and June, rising to 152% from July to October.
Modelling of weather patterns, and grass growth over the next 75 years, shows increased yields in spring and autumn, with static growth in summer months.
“This will inevitably create huge challenges to utilise grass in the shoulders of the year,” said AFBI’s Naomi Rutherford.
Quoting figures from beef and sheep farms in the GrassCheck programme, there is a differential of 4.8t/ha in grass dry matter utilised. For every additional tonne of grass dry matter utilised, it generated £204 in profit.
Based on results from red clover silage and white clover grazing on two 10ha blocks, there was an 8t reduction in chemical fertiliser leading to a cost saving of £2,640, compared to ryegrass only swards.
“There was also an extra 2t DM/ha with the red clover silage swards over ryegrass swards that received 270kg/ha of nitrogen. Emissions were also lower” said Rutherford.
“Multispecies swards delivered higher liveweight gain in grazing trails with a 17% increase in young cattle compared to animals on ryegrass swards. They also have the added benefit of a more even grown curve through the summer months, helping to avoid a grazing deficit in July and early August.”
Feeding for 24-month-old
finishing systems
The average slaughter age of cattle destined for beef in Northern Ireland is 28 months. Just one third are finished at 24 months of age, or younger.
According to AFBI’s Francis Lively, reducing slaughter age to 24 months will reduce methane emissions by 17%.
“The start point to reduce slaughter age is forage. Feeding a high energy forage year round is crucial to drive weight gain.
“Cattle have a maintenance energy requirement. Once that energy demand is met, any surplus is directed to weight gain. The more high quality forage you can get into cattle, the higher the weight gain will be.
“It is possible to condense that energy intake with meal. But concentrate is ultimately an imported feed and increases the amount of phosphorous (P) on farms.
“Increased P creates water quality problems that farming has to address. So the more we can do with grass, the better,” said Lively.
Outlining weight gain targets, spring born suckler calves should be gaining 1.2kg/day from birth until weaning.
Over the first winter, weight gain should be in the region of 0.6kg/day, rising to 0.9kg/day during the second grazing.
“Well-managed, spring-born suckler-bred animals should be in the region of 550kg to 570kg at the end of the second grazing season.
“That allows an intensive 100 to 120 day finishing period to get animals into the 700kg territory and produce a 380kg to 400kg carcase.
“Good quality silage is crucial to weight gain in the shed. Weather can go against you when cutting, but if you set out to make high quality forage, there is the chance you will get the silage you want.”
Options for reducing ammonia
Trials looking at ammonia emissions from livestock were detailed to farmers with the outcomes from two farming scenarios presented.
The first trial looked at a dairy beef system finishing steers at 24 months of age with a 192 day grazing season.
Two thirds of slurry is stored in underground tanks and the remaining third being farmyard manure. Slurry is spread by splash plate and a mix of urea along with CAN is spread to drive grass growth.
The second option is a suckler cow to weaning system on LFA land with 100% slatted storage for slurry and no chemical fertiliser applied.
A combination of low emission slurry spreading (LESS), fitting mats in slatted sheds, extending grazing by two weeks, protected urea and regularly scraping slurry were employed to manage emissions.
In the dairy beef system, ammonia emissions were reduced by 34% through a combination of all five practices, rising to 42% in the LFA scenario.
Using LESS equipment was the single biggest factor to reduce ammonia in both trials and was advised as the best starting point for livestock farmers going forward.
Read more
Friesian cattle account for 30% of cattle kill in 2023
Tullamore Farm suckler and sheep open day launched
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