Good livestock management and efficient production systems are the best hope UK livestock farming has of meeting 2020 targets to reduce emissions by 20%, based on 1990 levels, a panel of ruminants experts has concluded.
This means a win-win situation for farms that are doing the basics right as profits improve and greenhouse gas (GHG) emissions drop, SAC consulting beef specialist Jimmy Hyslop told the recent ruminomics conference in Edinburgh on 10 November.
Benchmark targets such as increasing the productive life of dairy cows and reducing days to slaughter on beef and sheep farms are the quickest routes to lower GHG emissions per unit of output.
Meanwhile, many high-science mitigation strategies are yet to be shown to influence farm profit, added Dr Hyslop.
He championed net feed efficiency as a driver for the meat sector. “We can breed animals to improve the efficiency with which they convert feed into saleable product, both improving profit and cutting greenhouse gas emissions per kg of meat produced,” said Dr Hyslop.
“The animals we are looking for are producing the same level of output [as other breeds] but do this with lower feed consumption.”
Days to slaughter
Despite using more concentrates, intensive finishing systems are inherently more efficient than extensive finishing systems, he added. Slaughtering prime cattle at 30 months – which means they spend three summers at grass –requires 4-5 times the dry matter for every kg of liveweight gain that a 12-month slaughter age needs.
“It’s not about what percentage of gross energy intake per day is lost as methane,” explained Dr Hyslop. “What matters is how many days that animal exists on the planet.”
- At least a 20% reduction in emissions by 2020 (compared with 1990 levels)
- An increase of 20% in the share of renewable energy in final consumption
- A 20% increase in efficiency
Slaughtering at 12 months requires about 5-7kg of dry matter for every kg of liveweight gain, while slaughtering at 18 months requires 12kg, 24 months requires 16kg and 30 months requires about 20kg.
Calving at two years old
Robert Gilchrist, knowledge transfer specialist at Quality Meat Scotland, urged farmers to strive for first-calving heifers at 24 months rather than 30 months to save on feed usage and cut GHG emissions.
“A simple step like that could save up to 2t of DM a cow,” said Mr Gilchrist. “[By saving] 10kg DM/day over 180 days for each animal, a farm can run cows more effectively, both in terms of methane and carbon footprint and the feeding costs.”
What can science do?
Independent consultant Cledwyn Thomas believes most on-farm changes will be driven through genetics, with some elements of nutrition having a role to play.
In his view, lipids and oils are among the most promising additives the industry could be using to soak up hydrogen in the rumen to reduce methane production.
However, he warned that the future holds many tough questions, particularly regarding high-starch diets and whole-farm systems.
Six things your dairy cow should do
- Produce 1,200-1,400kg/ha of milk solids
- Calve every year
- Maintain body condition score (BCS) with changes in feed supply
- Consume 16-20kg DM/day from pasture
- Cope in a large-herd scenario
- Average 5.5 lactations
“High-starch diets do not necessarily reduce methane production,” said Prof Thomas. “You start to see reductions only at very high levels of concentrate proportion. In some high-forage diets, concentrates will actually bring an increase in methane.”
Furthermore, a farm cannot focus solely on methane. A high-soya bean or fatty diet is likely to use more land, he added.
Great progress has been made in The Netherlands in meeting and surpassing EU targets for 2020. Taking things a step further, the country now intends to reduce GHG emissions by 30%, with latest calculations suggesting 27% has already been achieved.
Erwin Koenen of Netherlands-based breeding company CRV puts this success down to good communication and implementation of research, praising dairy co-operative FrieslandCampina for its schemes that reward farmers for making an effort with climate change.
“There should be an incentive for a dairy farmer to invest time and effort in improving efficiency,” said Mr Koenen. “The benefit should not just be an increase in profitability; it should be rewarded another way.”
Tips for fine-tuning your herd
- Plan to have one calf from each cow every year
- Manage BCS
- Have sound, fertile bulls
- Ensure heifers conceive and meet target weights
- Keep animals healthy
- Reduce complicated calvings
- Find out what your herd health problems are and make sure you deal with them
- Breed to improve net feed efficiency – this also cuts GHG emissions for each kg of red meat produced
- Promote efficiency in feeding systems, increasing the ratio of liveweight gain to dry matter intake