Every product or service has a \u201ccarbon footprint,\u201d a measure of the environmental impact of creating or delivering it.<\/p>\n
A new study from the lab of Elias Uddin, assistant professor of animal science in the College of Agriculture, Health and Natural Resources<\/a> (CAHNR) determined a more accurate measure of the carbon footprint of milk produced in Bangladesh. This work was recently published in the Journal of Dairy Science<\/a>.<\/p>\n The key data used in this study were collected from the Bangladesh Agricultural University Dairy Farm during 2018\u20132023. Uddin\u2019s lab collaborated with researchers from Bangladesh Agricultural University on the study. They calculated emissions related to the cows\u2019 diet, including fertilizer used to grow feed, enteric emissions produced by the cows\u2019 digestive processes, and manure management. Enteric fermentation (digestion) accounted for 48% of emissions, followed by feed (24%), manure (20%), and energy used to run the farm (8%).<\/p>\n As per standard life cycle assessment (LCA) guideline, the data included not only emissions related to lactating cows but non-lactating members of the herd as well. \u201cYou have to account for those non-lactating animals, because those are part of the production system,\u201d Uddin says. \u201cYou cannot just avoid them because they don\u2019t produce milk.\u201d<\/p>\n This study did not include the emissions associated with the milk once it left the farm since they did not have access to data about how far the milk travelled and how it may have been processed after delivery.<\/p>\n On average, during the five-year period the carbon footprint of milk on the farm was 5.18 kilograms per kilogram of milk. This is a measure of how many kilograms of carbon are required to produce one kilogram of milk.<\/p>\n Previous work has held that dairy production in southeast Asia has a much higher carbon footprint than U.S. or European dairy farms. The carbon footprint of those farms is about 1 kg carbon emission per kilogram milk.<\/p>\n This calculation is based on the fact that American and European cattle are much more productive; each cow produces an average of 30 to 40 liters of milk a day compared to cattle in developing countries like Bangladesh which produce only four to eight liters of milk daily.<\/p>\n However, this study demonstrated that using farm-specific data and the Tier 2 equations proposed by the Intergovernmental Panel on Climate Change (IPCC) resulted in a 27% lower carbon footprint of milk compared with previous estimates based on the more generalized Tier 1 equations.<\/p>\n Critically, the cow\u2019s productivity increased by 63% over the five-year study period. This led to a 37% reduction in the carbon footprint over time. In 2018, the cows on the farm produced an average of 3.53 kilograms of milk per day. By 2023, they were producing 5.76 kilograms on average. The increase in productivity was due to genetic selection and improved management strategies, like balanced diet and more efficient feed management.<\/p>\n \u201cWe saw that increasing productivity is really a crucial thing, and very important to reduce the carbon footprint,\u201d Uddin says. \u201cIn developing countries, increasing efficiency and productivity is key to reducing carbon footprint rather than hitting only emissions mitigation strategies.\u201d<\/p>\n Another important factor is that in Bangladesh, cattle farms raise animals for both dairy and meat together (dual-purpose). In the U.S. these are usually separate operations. This means that using the same equation for both areas is not accurate. Only about 50% of emissions on a cattle farm in Bangladesh go towards milk production (called emission allocation), while in the U.S. this is closer to 90%.<\/p>\n This led the researcher to look at carbon footprint per unit of nutrient production such as the protein or calories for human consumption produced by the farm which accounts for the nutrients provided by both meat and dairy. This put the Bangladeshi farm on much more similar ground to U.S. producers allowing a fair comparison if necessary.<\/p>\n \u201cIf we use that traditional allocation method of emission, it overestimates emissions,\u201d Uddin says. \u201cBut if we use the specific allocation method that is applicable for production system in Bangladesh, it really gives you a different answer.\u201d<\/p>\n This work has impacts far beyond the specific farm as used in this study. Carbon footprint varies significantly between farms even within the same region. By looking closely at individual farms, as they did in this study, researchers can gain more informed insight and provide better recommendations for other farms.<\/p>\n \u201cWe can see which farms are doing better compared to others, and the farm that has a low footprint, the practices they\u2019re doing, can those be translated into key messages that can be used by other farmers to make changes?\u201d Uddin says.<\/p>\n Having accurate information about a product\u2019s carbon footprint will be increasingly important as environmental concerns become a more dominant factor in international commerce.<\/p>\n \u201cLet\u2019s say two different countries are exporting the same product at a similar price,\u201d Uddin says. \u201cIf one is more environmentally friendly than the other, importers are going to prefer the one that is environmentally friendly.\u201d<\/p>\n <\/p>\n This work relates to CAHNR\u2019s Strategic Vision area focused on\u00a0<\/em>Advancing Adaptation and Resilience in a Changing Climate.<\/em><\/a><\/p>\n