Researchers in New Zealand (NZ) are making significant progress in developing technologies that reduce greenhouse gas emissions from ruminant livestock.
Agriculture accounts for 48% of total greenhouse gas emissions in NZ and methane, which mainly comes from ruminant livestock, is responsible for 75-80% of this.
By comparison, the accounting system currently used by DAERA suggests that agriculture is responsible for 27% of emissions in NI, with 65% of this coming from methane.
NZ has ambitious climate change targets which require a 10% drop in methane emissions by 2030 and a reduction between 24% to 47% is needed by 2050.
Mark Aspin, general manager of the Pastoral Greenhouse Gas Research Consortium (PGGRC), makes clear that focusing solely on improving on-farm efficiencies will not allow NZ farmers to meet these targets.
“Running an efficient business is very important, but it doesn’t have a massive effect on gross emissions. If you have a 10%, 24% or 47% reduction target, efficiency is not going to get you there,” he said.
PGGRC is funded by a collaboration between NZ farmers, industry bodies and government. Its main aim is to provide knowledge and tools for farmers to reduce greenhouse gas emissions.
Aspin, along with methane mitigation scientist Dr Peter Janssen from AgResearch NZ, spoke to members of the NI Institute of Agricultural Science last week.
A low methane emission trait which has been found in sheep should also be present in cattle.
“Methane production from pastorally fed ruminants is directly proportional to the quantity of feed consumed,” Aspin said during the online event.
“There is a little variation between pasture species, feed quality and animal type. It’s nearly all about how much they eat. It accounts for 85% of the variation,” he explained.
Research aim
The aim of the ongoing research in NZ is to develop technologies which break the link between dry matter intake of feed and methane emissions.
This is because livestock output, such as milk yield and carcase weight, is also controlled by the amount of feed that an animal consumes.
“What we are trying to do is decouple the methane from the feed, without decoupling the production,” Peter Janssen said.
The researchers are focused on four key areas, namely livestock genetics, nutrition, inhibitors and vaccination.
Methane is produced in an animal’s rumen by microbes known as methanogens. All the technologies being developed effectively reduce the activity of methanogens, which leads to lower emissions.
Janssen has found that across a variety of ruminant species and diets, methanogens are largely the same. It means that methane reduction technologies are likely to be applicable worldwide.
Dr Peter Janssen does not foresee a switch to higher concentrate usage on New Zealand dairy farms.
Four technologies to transform livestock farming
Genetics
Research in NZ on breeding livestock to produce lower methane emissions has mainly focused on sheep to date, and has produced promising results.
The low emission trait in sheep is heritable, at around 0.2, so it is similar to common production traits. The researchers are confident that a similar trait can be identified in cattle.
At present, emissions from the low methane sheep are 6% less than the national average. This result has come from just three generations of selection. How low the methane yield can go is currently unknown.
“These animals have a smaller rumen, but they don’t eat less or have less production. Things like number of live lambs, or daily liveweight gain are not compromised by being a low methane animal” Janssen said. “They have different types of microbes and they produce less hydrogen, so you therefore get less methane,” he explained.
Nutrition
Grain-based diets can substantially lower methane emissions from ruminants, with studies showing reductions of up to 50%.
NZ farming is dominated by low input, grass-based livestock systems and Janssen does not foresee a switch to higher concentrate usage, despite its potential to reduce emissions.
His team have investigated methane yields from different types and qualities of forages such as grass, clovers and chicories, but they found similar methane emissions per kilo of dry matter intake.
“We did find that forage rape gives 25-35% less methane per kilo of dry matter intake, and you get the same animal performance compared to pasture. Other brassicas also do this, but not as significantly,” Janssen said.
Fodder beet can reduce methane yields by 40%, but it has to be a large proportion of the animal’s diet.
“This is similar to grain. If you are below approximately 70% dry matter intake and the remainder of the diet is forage, you don’t get much methane reduction,” Janssen explained.
Inhibitors
The use of compounds to inhibit methanogens in the animal’s rumen was described by Janssen as “one of the really promising areas” of the ongoing research.
Various inhibitors are already available, but they generally need fed through a total mixed ration.
“Studies have shown that you can reduce methane by 30% or even more by using inhibitors with no negative effects on the animal,” Janssen said.
His team have identified a number of compounds which could be used on farms.
“We are developing our best one at the moment. It could be fed as a supplement given in the shed at milking or, perhaps more promising for our system, through a slow release device that dwells in the rumen,” he said.
The work on the product is now looking at things like persistence (does the effect wear off after repeated doses) and the potential for residues or issues with food safety.
Vaccination
Animal vaccination is often referred to as the “holy grail” of anti-methane technologies.
“We are very enthusiastic about this technology. It’s the most enticing, but it’s a really, really hard science,” Janssen acknowledged.
The aim is to stimulate the animal’s immune system to produce antibodies which interfere with the activity of methanogens in the rumen. The antibodies are delivered into the animal’s mouth through saliva and they steadily make their way to the rumen.
“Our target is greater than a 20% reduction, although we don’t know how high it could go,” he said.
A vaccine would also be less difficult to get on to the market than inhibitors, with a timescale of five to seven years expected for regulatory checks and production.
At present, the researchers have successfully developed a vaccine that leads to production of the correct antibodies, but lower methane emissions has not yet been seen.
“We have some ideas in the last few months of what the issues might be. We are working on overcoming those to make the vaccine effective,” Janssen said.
Researchers in New Zealand (NZ) are making significant progress in developing technologies that reduce greenhouse gas emissions from ruminant livestock.
Agriculture accounts for 48% of total greenhouse gas emissions in NZ and methane, which mainly comes from ruminant livestock, is responsible for 75-80% of this.
By comparison, the accounting system currently used by DAERA suggests that agriculture is responsible for 27% of emissions in NI, with 65% of this coming from methane.
NZ has ambitious climate change targets which require a 10% drop in methane emissions by 2030 and a reduction between 24% to 47% is needed by 2050.
Mark Aspin, general manager of the Pastoral Greenhouse Gas Research Consortium (PGGRC), makes clear that focusing solely on improving on-farm efficiencies will not allow NZ farmers to meet these targets.
“Running an efficient business is very important, but it doesn’t have a massive effect on gross emissions. If you have a 10%, 24% or 47% reduction target, efficiency is not going to get you there,” he said.
PGGRC is funded by a collaboration between NZ farmers, industry bodies and government. Its main aim is to provide knowledge and tools for farmers to reduce greenhouse gas emissions.
Aspin, along with methane mitigation scientist Dr Peter Janssen from AgResearch NZ, spoke to members of the NI Institute of Agricultural Science last week.
A low methane emission trait which has been found in sheep should also be present in cattle.
“Methane production from pastorally fed ruminants is directly proportional to the quantity of feed consumed,” Aspin said during the online event.
“There is a little variation between pasture species, feed quality and animal type. It’s nearly all about how much they eat. It accounts for 85% of the variation,” he explained.
Research aim
The aim of the ongoing research in NZ is to develop technologies which break the link between dry matter intake of feed and methane emissions.
This is because livestock output, such as milk yield and carcase weight, is also controlled by the amount of feed that an animal consumes.
“What we are trying to do is decouple the methane from the feed, without decoupling the production,” Peter Janssen said.
The researchers are focused on four key areas, namely livestock genetics, nutrition, inhibitors and vaccination.
Methane is produced in an animal’s rumen by microbes known as methanogens. All the technologies being developed effectively reduce the activity of methanogens, which leads to lower emissions.
Janssen has found that across a variety of ruminant species and diets, methanogens are largely the same. It means that methane reduction technologies are likely to be applicable worldwide.
Dr Peter Janssen does not foresee a switch to higher concentrate usage on New Zealand dairy farms.
Four technologies to transform livestock farming
Genetics
Research in NZ on breeding livestock to produce lower methane emissions has mainly focused on sheep to date, and has produced promising results.
The low emission trait in sheep is heritable, at around 0.2, so it is similar to common production traits. The researchers are confident that a similar trait can be identified in cattle.
At present, emissions from the low methane sheep are 6% less than the national average. This result has come from just three generations of selection. How low the methane yield can go is currently unknown.
“These animals have a smaller rumen, but they don’t eat less or have less production. Things like number of live lambs, or daily liveweight gain are not compromised by being a low methane animal” Janssen said. “They have different types of microbes and they produce less hydrogen, so you therefore get less methane,” he explained.
Nutrition
Grain-based diets can substantially lower methane emissions from ruminants, with studies showing reductions of up to 50%.
NZ farming is dominated by low input, grass-based livestock systems and Janssen does not foresee a switch to higher concentrate usage, despite its potential to reduce emissions.
His team have investigated methane yields from different types and qualities of forages such as grass, clovers and chicories, but they found similar methane emissions per kilo of dry matter intake.
“We did find that forage rape gives 25-35% less methane per kilo of dry matter intake, and you get the same animal performance compared to pasture. Other brassicas also do this, but not as significantly,” Janssen said.
Fodder beet can reduce methane yields by 40%, but it has to be a large proportion of the animal’s diet.
“This is similar to grain. If you are below approximately 70% dry matter intake and the remainder of the diet is forage, you don’t get much methane reduction,” Janssen explained.
Inhibitors
The use of compounds to inhibit methanogens in the animal’s rumen was described by Janssen as “one of the really promising areas” of the ongoing research.
Various inhibitors are already available, but they generally need fed through a total mixed ration.
“Studies have shown that you can reduce methane by 30% or even more by using inhibitors with no negative effects on the animal,” Janssen said.
His team have identified a number of compounds which could be used on farms.
“We are developing our best one at the moment. It could be fed as a supplement given in the shed at milking or, perhaps more promising for our system, through a slow release device that dwells in the rumen,” he said.
The work on the product is now looking at things like persistence (does the effect wear off after repeated doses) and the potential for residues or issues with food safety.
Vaccination
Animal vaccination is often referred to as the “holy grail” of anti-methane technologies.
“We are very enthusiastic about this technology. It’s the most enticing, but it’s a really, really hard science,” Janssen acknowledged.
The aim is to stimulate the animal’s immune system to produce antibodies which interfere with the activity of methanogens in the rumen. The antibodies are delivered into the animal’s mouth through saliva and they steadily make their way to the rumen.
“Our target is greater than a 20% reduction, although we don’t know how high it could go,” he said.
A vaccine would also be less difficult to get on to the market than inhibitors, with a timescale of five to seven years expected for regulatory checks and production.
At present, the researchers have successfully developed a vaccine that leads to production of the correct antibodies, but lower methane emissions has not yet been seen.
“We have some ideas in the last few months of what the issues might be. We are working on overcoming those to make the vaccine effective,” Janssen said.
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