Central to the debate around climate change and agriculture has been livestock’s contribution to emissions. Livestock play a part in agriculture’s carbon footprint; this fact is indisputable but the production of livestock brings many benefits to the UK food chain.
The Royal Agricultural Society of England (RASE) commissioned a piece of work looking at reducing emissions from livestock. This article, written by Dr David Garwes looks at the contribution livestock makes to the UK food chain, the environment and the farming industry in the UK. This report has examined various strategies that could be adopted in the coming years to help reduce GHG emissions and that may need further research. Some of these measures are summarised below, but to read the full report click here.
Reduced animal numbers
The most cost effective approach is to make every animal more productive, whilst continuing to meet food production needs.
Increased yield from each animal
Improving the genotype of cattle can generate increased yield (kg of meat or litre of milk). It may be possible to include selection traits that bring about a reduced environmental footprint. This would improve the cost of production.
Reduced breeding stock numbers
Improvements in reproductive performance of breeding stock will reduce the numbers of animals that are needed to generate productive offspring. A study from Nottingham University found that if dairy cow fertility returned to the level documented in 1995, methane emission from the national herd would fall by 11%.
Improved feed conversion
Feed is a significant proportion of rearing costs. Data highlighted in sector specific roadmaps show that there are significant differences between management practices and species in terms of efficiency.
Optimise feed intake
Selection of stock that consume only what is needed for optimal production will reduce pollution from excess nutrients.
Improve nutrient balance in rations
Better ration formulation will allow a balance to be met between nutrients produced and animal demand.
Feed sources that reduce methane and ammonia emissions
Increasing the availability of fermentable carbohydrates in dairy feed promotes higher milk yields and reduces the amount of Nitrogen lost through urination. Examples of plants to add to rations include clover and chicory (high in tannins) and red clover (high in polyphenol oxidase).
Reducing leaching losses and covering slurry storage can be options to consider. Future developments include using nitrification inhibitors and scrubbing effluent air from production units to reduce emissions to the atmosphere.
Use manures as a resource
Apply manure precisely based on nutrient content and crop requirements. The faster slurry can be incorporated into the soil, the lower the nitrous oxide emissions will be,