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Diurnal and Seasonal Patterns of Methane Emissions from a Dairy Operation in North China Plain  [PDF]
Zhiling Gao,Huijun Yuan,Wenqi Ma,Jianguo Li,Xuejun Liu,Raymond L. Desjardins
Advances in Meteorology , 2011, DOI: 10.1155/2011/190234
Abstract: In China, dairy cattle managed in collective feedlots contribute about 30% of the milk production and are believed to be an important contributor to national methane emissions. Methane emissions from a collective dairy feedlot in North China Plain (NCP) were measured during the winter, spring, summer, and fall seasons with open-path lasers in combination with an inverse dispersion technique. Methane emissions from the selected dairy feedlot were characterized by an apparent diurnal pattern with three peaks corresponding to the schedule of feeding activities. On a per capita basis, daily methane emission rates of these four seasons were 0.28, 0.32, 0.33, and 0.30?kg?head?1?d?1, respectively. In summary, annual methane emission rate was 112.4?kg?head?1?yr?1 associated with methane emission intensity of 32.65?L CH4 L?1 of milk and potential methane conversion factor Ym of 6.66% of gross energy intake for mature dairy cows in North China Plain. 1. Introduction The dairy cow population in China has increased from 40,000 animals to 13.25 million animals during the period of 1949–2006. Dairy production has become one of the most profitable and increasing industries in the agriculture sector in China. For example, in 2008, the GDP originated from Chinese dairy industry was ¥101.5 billion, which accounted for about 10% of the total animal production and about 3.0% of total agricultural production [1]. Considerable efforts have been made to estimate enteric methane emissions from dairy cows in China in order to improve the accuracy of national methane inventory [2–4]. These inventories are mainly based on the Intergovernmental Panel on Climate Change (IPCC) methodology. However, many studies have demonstrated that methane emissions from ruminants are strongly influenced by factors such as feeding activity, composition of feedstuffs, and use of additives, which are not included in the IPCC methodology. In China, management practices are frequently different from one dairy facility to another; hence, large uncertainties in the inventory estimates are anticipated. Dairy cattle in China are being managed in different types of dairy facilities. Based on the number of animals, these facilities are either classified as intensive, collective, or household level operations [5]. As reported by Ma et al. [6], about 45%, 29.3%, and 25.9% of the Chinese dairy cow population is held in household, collective, and intensive dairy facilities, respectively, and the collective dairy feedlot has been considered a transition phase that links the transformation from household to
Ruminal methane emission by dairy cattle in Southeast Brazil
Pedreira, Márcio dos Santos;Primavesi, Odo;Lima, Magda Aparecida;Frighetto, Rosa;Oliveira, Simone Gisele de;Berchielli, Telma Teresinha;
Scientia Agricola , 2009, DOI: 10.1590/S0103-90162009000600004
Abstract: ruminal gases, particularly methane, generated during the fermentative process in rumen, represent a partial loss of feed energy and are also pointed to as an important factors in greenhouse effect. this study aimed at quantifying methane (ch4) emission rates from lactating and dry cows and heifers, 24 month-old in average, on pasture under southeast brazil tropical conditions, using the tracer gas technique, sulphur hexafluoride (sf6), four animals per category, distributed in four blocks. measurements were performed in february and june, 2002, with holstein and brazilian dairy crossbred (holstein ? x gir (zebu) ?), maintained on fertilized tanzania-grass (panicum maximum jacq. cv. tanzania) and fertilized brachiaria-grass (brachiaria decumbens cv. basilisk) pastures. heifers of both breeds were maintained on unfertilized brachiaria-grass to simulate conditions of extensive cattle farming systems. ch4 and sf6 levels were measured with gas chromatography. differences in ch4 emissions were measured (p < 0.05) for genetical groups. holstein produced more methane (299.3 g day-1) than the crossbred (264.2 g day-1). lactating cows produced more methane (353.8 g day-1) than dry cows (268.8 g day-1) and heifers (222.6 g day-1). holstein, with greater milk production potential, produced less ch4 (p < 0.05) per unit of dry matter intake (19.1 g kg-1) than the crossbred (22.0 g kg-1). methane emission by heifers grazing fertilized pasture (intensive system) was 222.6 g day-1, greater (p < 0.05) than that of heifers on unfertilized pasture (179.2 g day-1). methane emission varied as function of animal category and management intensity of production system.
Diurnal and Seasonal Patterns of Methane Emissions from a Dairy Operation in North China Plain  [PDF]
Zhiling Gao,Huijun Yuan,Wenqi Ma,Jianguo Li,Xuejun Liu,Raymond L. Desjardins
Advances in Meteorology , 2011, DOI: 10.1155/2011/190234
Abstract: In China, dairy cattle managed in collective feedlots contribute about 30% of the milk production and are believed to be an important contributor to national methane emissions. Methane emissions from a collective dairy feedlot in North China Plain (NCP) were measured during the winter, spring, summer, and fall seasons with open-path lasers in combination with an inverse dispersion technique. Methane emissions from the selected dairy feedlot were characterized by an apparent diurnal pattern with three peaks corresponding to the schedule of feeding activities. On a per capita basis, daily methane emission rates of these four seasons were 0.28, 0.32, 0.33, and 0.30 kg head−1 d−1, respectively. In summary, annual methane emission rate was 112.4 kg head−1 yr−1 associated with methane emission intensity of 32.65 L CH4 L−1 of milk and potential methane conversion factor Ym of 6.66% of gross energy intake for mature dairy cows in North China Plain.
Methane Emissions from the Cattle Population in Uganda
F. Ejobi,J.D. Kabasa,J. Oloya,C. Ebong,J. Kabirizi,P. Isabirye,R. Livingston
Journal of Animal and Veterinary Advances , 2012,
Abstract: We used the Livestock Analysis Model (LAM) to estimate the current and projected amount of methane, a greenhouse gas, produced by the cattle population in Uganda in the period from 2000 to 2030. The LAM is a data-intensive computer model developed by the United States Environment Protection Agency. The data required for the model were derived from official documents of the Government of Uganda. Secondary data on human and cattle population and production target of beef and milk were subjected to stepwise regression analysis and the outputs were used in the LAM. Primary data for the LAM were also generated through a national livestock survey. According to the LAM, the total methane emissions from cattle in Uganda in the year 2000 were estimated at 337,796 tons. This amount is projected to nearly triple by the year 2030 unless appropriate mitigation measures are put in place in the country. Among indigenous cattle breeds, the Zebu and Nganda had the highest methane emissions per unit of product, generating approximately 1 kilogram of methane per kilogram of milk produced, while the Ankole cattle emitted approximately 0.566 kg of methane per kilogram of milk produced. On the other hand, the improved breeds emitted only 0.123 kg of methane per kilogram of milk produced. The results of this study show that the cattle sector in Uganda has a potential for international investments for reduction of methane emissions in line with the Clean Development Mechanism under the Kyoto Protocol.
Ammonia Emissions from Dairy Cattle Barns in Summer Season
Ercan Simsek,Ilker Kilic,Erkan Yaslioglu,Ismet Arici
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.2116.2120
Abstract: The objective of this study was to determine magnitude of ammonia emissions from dairy cattle free-stall barns with natural ventilation. The measurements of ammonia concentration and indoor environmental conditions in barns were done throughout the 4 days in three dairy farms in summer season. The overall hourly average temperature and relative humidity for all barns were 26.5°C and 61%, respectively. In monitored dairy cattle barns, ammonia concentrations were observed between 0.4 and 8.77 ppm. The overall hourly average ammonia emission was calculated as 56.1 g/h.barn. Ammonia concentrations increased with lower airflow rate while ammonia emissions increased with higher airflow rate. As a result of this study, there is no significant relationship observed between ammonia emission and indoor environmental conditions such as temperature and relative humidity.
Greenhouse Gas Emissions from Ground Level Area Sources in Dairy and Cattle Feedyard Operations  [PDF]
Md Saidul Borhan,Sergio C. Capareda,Saqib Mukhtar,William B. Faulkner,Russell McGee,Calvin B. Parnell
Atmosphere , 2011, DOI: 10.3390/atmos2030303
Abstract: A protocol that consisted of an isolation flux chamber and a portable gas chromatograph was used to directly quantify greenhouse gas (GHG) emissions at a dairy and a feedyard operation in the Texas Panhandle. Field sampling campaigns were performed 5 consecutive days only during daylight hours from 9:00 am to 7:00 pm each day. The objective of this research was to quantify and compare GHG emission rates (ERs) from ground level area sources (GLAS) at dairy and cattle feedyard operations during the summer. A total of 74 air samples using flux chamber were collected from the barn (manure lane and bedding area), loafing pen, open lot, settling basin, lagoons, and compost pile within the dairy operation. For the cattle feedyard, a total of 87 air samples were collected from four corner pens of a large feedlot, runoff holding pond, and compost pile. Three primary GHGs (methane, carbon dioxide, and nitrous oxide) were measured and quantified from both operations. The aggregate estimated ERs for CH 4, CO 2, and N 2O were 836, 5573, 3.4 g hd ?1 d ?1 (collectively 27.5 kg carbon dioxide equivalent (CO 2e) hd ?1 d ?1), respectively, at the dairy operation. The aggregate ERs for CH 4, CO 2, and N 2O were 3.8, 1399, 0.68 g hd ?1 d ?1 (1.7 kg CO 2e hd ?1 d ?1), respectively, from the feedyard. The estimated USEPA GHG ERs were about 13.2 and 1.16 kg CO 2e hd ?1 d ?1, respectively, for dairy and feedyard operations. Aggregate CH 4, CO 2 and N 2O ERs at the dairy facility were about 219, 4 and 5 times higher, respectively, than those at the feedyard. At the dairy, average CH 4 ERs estimated from the settling basin, primary and secondary lagoons were significantly higher than those from the other GLAS, contributing about 98% of the aggregate CH 4 emission. The runoff holding pond and pen surface of the feedyard contributed about 99% of the aggregate CH 4 emission. Average CO 2 and N 2O ERs estimated from the pen surface area were significantly higher than those estimated from the compost pile and runoff pond. The pen surface alone contributed about 93% and 84% of the aggregate CO 2 and N 2O emission, respectively. Abatement and management practices that address GHG emissions from these sources will likely be most effective for reducing facility emissions.
Methane emissions during storage of di erent treatments from cattle manure in Tianjin

Jiajun Wang,Chiqing Duan,Yaqin Ji,Yichao Sun,

环境科学学报(英文版) , 2010,
Abstract: Many studies on methane emissions from animal manure have revealed that animal manure is a major source of methane emissions to the atmosphere that can have negative consequences for people, animals and environment. In general, the release of methane can be influenced by the type of feed taken by animals, temperature, manure characteristics and so on. This study aimed at quantifying and comparing methane release from dairy manure with di erent piling treatments. Four treatments were designed including manure piling height 30, 45, 60 cm and adding 6 cm manure every day until the piling height was 60 cm. Static chamber method and gas chromatography were adopted to measure the methane emissions from April to June in 2009. Methane emission rates of all four manure treatments were low in the first week and then increased sharply until reaching the peak values. Subsequently, all the methane emission rates decreased and fluctuated within the steady range till the end of the experiment. Wilcoxon nonparametric tests analysis indicated that methane emission rate was greatly influenced by manure piling height and manner. There were no significant relationships between methane emission rates and the temperatures of ambience and heap. However, regression analysis showed that the quadratic equations were found between emission rates of all treatments and the gas temperature in the barrels.
Prediction of Ruminal Methane Production from Cattle
Sang-Moon Lee,Jin-Suk Jeong,Sang-Cheol Lee,Kyu-Hyun Park,Seongwon Seo
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.3228.3233
Abstract: Methane, one of the major greenhouse gases is produced primarily from cattle among livestock. Many researches have been conducted to reduce methane production and also to develop methods and/or equations to predict methane production in cattle. The objectives of this study were thus to construct a database containing experimental observations of methane production from cattle and to develop equations that predict methane production by cattle accurately. The database developed in this study contains experimental observations from the research articles published in the Journal of Dairy Science, Journal of Animal Science, Animal Feed Science and Technology, Canadian Journal of Animal Science, International Congress Series and Journal of Nutrition from 1964 till 2009. A total of 350 treatment means from 75 studies were obtained from the scientific journal articles that were found by searching for with methane and cattle as keywords. There were different methods measuring methane production; a chamber system, indirect respiratory hood, Sulfur hexafluoride (SF6) and stoichiometric calculation. Only measured data were used in the subsequent analysis. Consequently the actual database used for the analysis is composed of a total of 256 treatment means from 57 studies. The types of animal in the database were 110 lactating dairy cows, 12 non-lactating dairy cows, 47 heifers, 65 steers, 10 calves, 10 bulls and 2 mixed. The mean (±SD) methane (g day-1) methane (Mcal day-1) and methane (GE%) of the data were 204.50 (±104.22), 2.76 (±1.38) and 5.56 (±1.87), respectively. Among the variables tested, DMI (kg) or NDF intake (NDFI, kg) was the most significant single variable that correlates with methane production. Using a random coefficient model with study as a random effect, researchers obtained -24.27 (±17.76) + 13.93 (±1.68) DMI (kg) + 0.57 (±0.20) FpDM + 8.43 (±4.16) NDFI (kg) (n = 145, -2 Res log likelihood = 1434.9) for predicting methane production (g). Using a simple linear regression, the best equation was CH4 (g) = 18.53 (±14.90) + 11.89 (±1.50) DMI (kg) + 0.49 (±0.18) FpDM + 14.19 (±3.77) NDFI (kg) (R2 = 0.84, root mean square error = 42.25). Although, DMI and NDFI are inherently correlated, a single variable was not sufficient to explain the variations in methane production of cattle. When both NDFI and DMI were present in the model statement type of animal or method of methane measurement was no longer significant. The results from this study suggest that methane production from cattle can be predicted accurately with DMI and NDFI. More research however is needed to improve accuracy of the model predictions.
An Essential Oil Blend Decreases Methane Emissions and Increases Milk Yield in Dairy Cows  [PDF]
Kenton J. Hart, Hefin G. Jones, Kate E. Waddams, Hilary J. Worgan, Beatrice Zweifel, C. Jamie Newbold
Open Journal of Animal Sciences (OJAS) , 2019, DOI: 10.4236/ojas.2019.93022
Abstract: This study was conducted to investigate the effect of a commercial essential oil (EO) additive on milk production and methane (CH4) emissions from dairy cows. Early lactation Holstein-Friesian dairy cows were fed grass, whole crop wheat and corn silage total mixed ration. Cows were allocated to one of two experimental treatments: Control (no additive, CON) or 1 g/head/day of EO. Cows were housed in a free stall barn, split into two pens for the duration of the experiment. Two gas data loggers units used to measure CH4 emissions were provided per pen for the duration of the 22 week-long study. Milk yield was determined daily, and milk components were analyzed every two weeks. CH4 was recorded continuously, and daily values were tabulated. Body weight and body condition score were determined at the start and bi-weekly. Results were analyzed as a randomized complete block trial. In total, 149 cows participated in the study (76 CON, 73 EO). Milk yields were greater (P < 0.05) for the test treatment (28.3 CON, 31.2 EO) with no change in milk component concentrations. Milk component concentrations were unaffected (P > 0.05) by treatment. Yields of fat, protein, lactose, and solids were higher for EO fed cows (P < 0.05). CH4 output was reduced with the EO compared to the CON treatment (411 g/day vs 438 g/day; 13.8 g/L of milk vs 17.2 g/L of milk, P < 0.05) over the duration of the trial. There were no effects of treatment on reproductive performance or the occurrence of mastitis. Feeding EO to dairy cows reduced CH4 emissions whilst also increasing performance.
Replacement of Cereal with Low Starch Fibrous By-Products on Nutrients Utilization and Methane Emissions in Dairy Goats  [PDF]
Carla Ibá?ez, Vicente Javier Moya, Haritz Arriaga, Diana María López, Pilar Merino, Carlos Fernández
Open Journal of Animal Sciences (OJAS) , 2015, DOI: 10.4236/ojas.2015.52022
Abstract: Feeding systems for dairy ruminants need to ensure high intake of energy to achieve maximum milk production potential. This might be accomplished by raising the dietary concentration of cereal grain. Increasing the concentration of starch in diets can lead to undesirable ruminal fermentation, and to prevent it, the partial replacement of cereal grain with low starch by-product feeds is recommended. The purpose of the present study was to compare the effect of fed two mixed diets to dairy goats differing in the type of carbohydrate (starch vs. easily degradable fiber). Energy and nitrogen balance, short chain fatty acids in rumen liquor and milk performance in dairy goats during mid lactation were determined. Enteric methane (CH4) emissions and CH4 production from manure were determined as well. Ten multiparous Muciano-Granadina goats were assigned to two isoenergetic and isoproteic diets (19.1 MJ/kg dry matter (DM) and 18.1% of CP, DM basis) in a crossover design. One group was fed a mixed ration with 21.9% of starch (HS diet) and the other (LS diet) with 7.0% of starch. HS diet had 36% of barley (as source of starch) and it was replaced with soy hulls and corn gluten feed in LS diet (as potentially digestible fiber). No differences were observed for dry matter intake in both diets (2.05 kg/d, on average). A significant increase of ruminal acetic acid was found for low starch diet (66.4 and 56.6 mol/100 mol for LS and HS diet, respectively). No significant effect was found among diets for enteric CH4 emissions (28.5 g/d, on average). Manure derived maximum potential yield was (Bo) higher in HS diet, with 5.9 L CH4/kg OM vs. 0.28 L CH4/kg OM for LS diet, probably associated with the low ADF digestibility. Differences among diets were found for milk production (2.4 vs. 2.2 kg/d for HS and LS, respectively), and greater milk fat was observed with LS diet compared with HS (6.4% vs. 5.5%, respectively).
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