Dairy Emissions

The Dairy Emissions Publications section focuses on the critical issue of greenhouse gas emissions from dairy operations. This collection of research articles, reports, and case studies provides in-depth insights into the sources, impacts, and mitigation strategies for emissions within the dairy industry.

Our publications address various aspects of dairy emissions, including methane and nitrous oxide emissions from livestock, manure management practices, feed strategies, and technological innovations aimed at reducing the carbon footprint of dairy farming. By exploring these topics, we aim to equip farmers, researchers, and policymakers with the knowledge needed to implement effective emissions reduction strategies.

Explore our resources to learn about cutting-edge research and practical solutions that are helping the dairy industry move towards the goal of net-zero emissions by 2050. Together, we can make dairy farming more sustainable and environmentally friendly while maintaining productivity and economic viability. Join us in our commitment to reducing dairy emissions and protecting our planet for future generations.

Dairy Emissions Publications

On-Farm Testing of a Zeolite Filter to Capture Ammonia and Odors from a Dairy Manure Flushing System

de Haro Martí, Mario Emanuel ; Neibling, William Howard ; Chen, Lide ; Chahine, Mireille

A zeolite filter achieved 92% reduction in ammonia emissions from a dairy flushed manure pit. The reduction in odor concentration was 45% at a minimum filter residence time of 0.9 seconds. The on-farm filter and air collection structure over a manure pit demonstrated the applicability of the project. Abstract. The concentration of large numbers of animals in relatively small areas, high production output per animal unit, and concentration of animal excretions and air emissions are some of the characteristics of modern animal agriculture. Ammonia (NH3) and odors are among the most noticeable as well as locally and regionally problematic emissions generated by concentrated animal feeding operation (CAFO) dairy production systems. Zeolites are defined as aluminosilicates with open three-dimensional framework structures composed of corner-sharing TO4 tetrahedra, where T is Al or Si. Zeolites are able to lose or gain water reversibly and to exchange and retain cations, including NH3 and ammonium. This study demonstrated the design and performance of a zeolite filter treating the airstream from a flushed manure pit installed on-farm at a commercial dairy. Clinoptilolite zeolite mined in Idaho was used as the filter medium. The capacity of the filter to reduce NH3 emissions was tested at three, six, and 59 days of filter operation. Reduction of odor emissions was tested at six days of operation. NH3 emissions were reduced by 92% (p < 0.001) at three days of operation and by 42% (p = 0.13) at 59 days of operation. The ammonia concentration in the pre-treatment airstream from a dairy manure collection pit was relatively high at 5.287 ±0.04 mg NH3-N m-3 (p < 0.001). The odor concentration reduction was 45% (p = 0.001) at six days of operation with the minimum empty bed residence time of 0.9 s. Total trial running time was 59 days. The roof-like pit cover structure used for air collection and the zeolite filter were proven to be capable of operating in the harsh on-farm environment and to be adaptable to changing operating conditions within the dairy.

Estimation of Tunisian Greenhouse Gas Emissions from Different Livestock Species

Ammar, Hajer ; Abidi, Sourour ; Ayed, Mediha ; Moujahed, Nizar ; deHaro Martí, Mario E. ; Chahine, Mireille ; Bouraoui, Rachid ; López, Secundino ; Cheikh M’hamed, Hatem ; Hechlef, Haikel

This study aimed to determine the emissions of methane (CH4) and nitrous oxide (N2O) from seven Tunisian livestock species and their evolution over eleven consecutive years (2008–2018). The species of animals used were cattle (dairy and others), sheep, goats, camelids, horses, donkeys and mules, and poultry. The estimations of CH4 and N2O emissions were based on the Intergovernmental Panel on Climate Change (IPCC) guidelines for national inventories, using Tier 1 and Tier 2 approaches, with its default emission factors (EFs). The Tier 2 approach was applied only for the calculation of EF to estimate CH4 emissions related to livestock manure management. CH4 emission represented more than 92% of the total greenhouse gas (GHG) from livestock emissions. Moreover, 53% of the total CH4 emissions from livestock were derived from cattle, followed by sheep, goats, other mammals (camelids, horses, mules, and donkeys), and poultry. During the period covered by the study (2008–2018), a slight and continuous decrease of both livestock population and total GHG emissions was observed, mainly in terms of CH4. In mammals, CH4 emissions were greater than N2O emissions, whereas in poultry, N2O emissions were up to 2.6 times greater than CH4 emissions. The aggressive drive of the government to increase cattle and sheep production might affect CH4 emissions in the future. Therefore, periodic estimations of GHG emissions from livestock are required to follow the time trends for more rational decision-making regarding livestock and GHG emissions policies.

Effects of spray-dried plasma protein in diets of early lactation dairy cows on health, milking and reproductive performance

Chahine, Mireille ; de Haro Marti, Mario E. ; Matuk, Celina ; Aris, Anna ; Campbell, Joy ; Polo, Javier ; Bach, Alex

Feeding SDP during transition improves milk production and milk fat content.•No negative effect on reproductive performance when SDP is included in transition feed.•The inclusion of SDP in transition feed has no detrimental effect on health performance. Spray-dried plasma (SDP) proteins are recognized as safe, high-quality feed ingredients for livestock due to their immune modulatory components, including immunoglobulins, bioactive peptides and growth factors. The objective of this study was to investigate the effects of feeding a SDP product during the first 200 d of lactation on milk production and reproduction performance in dairy cows. Nine hundred ninety-eight Holstein cows, 260 d pregnant, were enrolled in a completely randomized design. Before calving, cows were fed a late gestation ration containing blood meal (BM; 13.3 g/kg of DM; Control; n = 503) or SDP (16.0 g/kg of DM; 250 g SDP/d; n = 495) replacing BM on N basis. After calving, Control cows were randomly distributed in two pens and fed a lactation ration containing 15.6 g/kg BM (DM basis). Cows on SDP were randomly distributed in 2 pens and fed a lactation ration that contained 18.3 g/kg SDP (DM basis. 400 g/d of SDP), which replaced BM. Cows were milked three times per day and milk production and composition were monitored monthly at one milking. First service consisted of a timed AI protocol applied to all cows that were > 44–50 DIM. Following AI, cows were examined daily for return to estrus or for confirmation of pregnancy by rectal palpation at 35–41 and 70–76 d after AI. At 72–78 DIM, cows not pregnant were enrolled into an intrauterine progesterone program. Cows fed SDP had greater milk yield (P < 0.01; 16.8 vs 16.4 kg/milking) and milk fat (P < 0.05; 35.5 vs 34.7 g/kg), but there were no differences in milk protein or in milk SCC between Control and SDP cows. Milk yield improvement in SDP cows was evident during the second month of lactation and onwards. No differences in pregnancy rate, overall conception rate, days at which pregnancy occurred or body condition score were observed between treatments. In conclusion, supplementation with SDP in dairy cows slightly increased milk yield and milk fat content without affecting reproductive parameters.