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2011. Review: Ammonia emissions from dairy farms and beef feedlots. Can. J. Anim. Sci. 91: 1Á35. Ammonia emitted from animal feeding operations is an environmental and human health hazard, contributing to eutrophication of surface waters and nitrate contamination of ground waters, soil acidity, and fine particulate matter formation. It may also contribute to global warming through nitrous oxide formation. Along with these societal concerns, ammonia emission is a net loss of manure fertilizer value to the producer. A significant portion of cattle manure nitrogen, primarily from urinary urea, is converted to ammonium and eventually lost to the atmosphere as ammonia. Determining ammonia emissions from cattle operations is complicated by the multifaceted nature of the factors regulating ammonia volatilization, such as manure management, ambient temperature, wind speed, and manure composition and pH. Approaches to quantify ammonia emissions include micrometeorological methods, mass balance accounting and enclosures. Each method has its advantages, disadvantages and appropriate application. It is also of interest to determine the ammonia emitting potential of manure (AEP) independent of environmental factors. The ratio of nitrogen to non-volatile minerals (phosphorus, potassium, ash) or nitrogen isotopes ratio in manure has been suggested as a useful indicator of AEP. Existing data on ammonia emission factors and flux rates are extremely variable. For dairy farms, emission factors from 0.82 to 250 g ammonia per cow per day have been reported, with an average of 59 g per cow per day (n 031). Ammonia flux rates for dairy farms averaged 1.03 g m (2 h (1 (n 024). Ammonia losses are significantly greater from beef feedlots, where emission factors average 119 g per animal per day (n 09) with values as high as 280 g per animal per day. Ammonia flux rate for beef feedlots averaged 0.174 g m (2 h (1 (n 012). Using nitrogen mass balance approaches, daily ammonia nitrogen losses of 25 to 50% of the nitrogen excreted in manure have been estimated for dairy cows and feedlot cattle. Practices to mitigate ammonia emissions include reducing excreted N (particularly urinary N), acidifying ammonia sources, or binding ammonium to a substrate. Reducing crude protein concentration in cattle diets and ruminal protein degradability are powerful tools for reducing N excretion, AEP, and whole-farm ammonia emissions. Reducing dietary protein can also benefit the producer by reducing feed cost. These interventions, however, have to be balanced with the risk of lost production. Manure treatment techniques that reduce volatile N species (e.g., urease inhibition, pH reduction, nitrification-denitrification) are also effective for mitigating ammonia emissions. Another option for reducing ammonia emissions is capture and treatment of released ammonia. Examples in the latter category include biofilters, permeable and impermeable covers, and manure incorporation into the soil for crop or pasture production. Process-level simulation of ammonia formation and emission provides a useful tool for estimating emissions over a wide range of production practices and evaluating the potential benefits of mitigation strategies. Reducing ammonia emissions from dairy and beef cattle operations is critical to achieving environmentally sustainable animal production that will benefit producers and society at large.
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... Although urea is quantitatively the most important N compound in urine, other N compounds are important as well in N 2 O emissions related to urine . Farm animals are considered the main contributors to NH 3 emissions, contributing, for instance, 50% of NH 3 emissions in the United States (Hristov et al., 2011). When urine and feces are mixed, urease present in feces rapidly converts urea excreted in urine into NH 3 and NH 4 + , resulting in NH 3 volatilization (Bougouin et al., 2016). ...
... When urine and feces are mixed, urease present in feces rapidly converts urea excreted in urine into NH 3 and NH 4 + , resulting in NH 3 volatilization (Bougouin et al., 2016). Therefore, urine N is the main contributor to NH 3 emission from manure (Hristov et al., 2011). ...
... However, CP digestibility might have a minor contribution compared with DMI, which is directly linked to metabolic and endogenous N and subsequent N losses in feces (Huhtanen et al., 2008). Nevertheless, variation in dietary N supply particularly affects urinary N output (Huhtanen et al., 2008), and nitrogen intake has been shown to be the main driver of N losses in dairy cows (Kebreab et al., 2010), milk N efficiency (Huhtanen and Hristov, 2009), and NH 3 emissions from manure (Hristov et al., 2011). Increasing N intake increases the amount of N excreted in urine as urea N in particular, which may lead to higher NH 3 emissions from manure (Weiss et al., 2009). ...
Article
Manure nitrogen (N) from cattle contributes to nitrous oxide and ammonia emissions and nitrate leaching. Measurement of manure N outputs on dairy farms is laborious, expensive, and impractical at large scales; therefore, models are needed to predict N excreted in urine and feces. Building robust prediction models requires extensive data from animals under different management systems worldwide. Thus, the study objectives were (1) to collate an international database of N excretion in feces and urine based on individual lactating dairy cow data from different continents; (2) to determine the suitability of key variables for predicting fecal, urinary, and total manure N excretion; and (3) to develop robust and reliable N excretion prediction models based on individual data from lactating dairy cows consuming various diets. A raw data set was created based on 5,483 individual cow observations, with 5,420 fecal N excretion and 3,621 urine N excretion measurements collected from 162 in vivo experiments conducted by 22 research institutes mostly located in Europe (n = 14) and North America (n = 5). A sequential approach was taken in developing models with increasing complexity by incrementally adding variables that had a significant individual effect on fecal, urinary, or total manure N excretion. Nitrogen excretion was predicted by fitting linear mixed models including experiment as a random effect. Simple models requiring dry matter intake (DMI) or N intake performed better for predicting fecal N excretion than simple models using diet nutrient composition or milk performance parameters. Simple models based on N intake performed better for urinary and total manure N excretion than those based on DMI, but simple models using milk urea N (MUN) and N intake performed even better for urinary N excretion. The full model predicting fecal N excretion had similar performance to simple models based on DMI but included several independent variables (DMI, diet crude protein content, diet neutral detergent fiber content, milk protein), depending on the location, and had root mean square prediction errors as a fraction of the observed mean values of 19.1% for intercontinental, 19.8% for European, and 17.7% for North American data sets. Complex total manure N excretion models based on N intake and MUN led to prediction errors of about 13.0% to 14.0%, which were comparable to models based on N intake alone. Intercepts and slopes of variables in optimal prediction equations developed on intercontinental, European, and North American bases differed from each other, and therefore region-specific models are preferred to predict N excretion. In conclusion, region-specific models that include information on DMI or N intake and MUN are required for good prediction of fecal, urinary, and total manure N excretion. In absence of intake data, region-specific complex equations using easily and routinely measured variables to predict fecal, urinary, or total manure N excretion may be used, but these equations have lower performance than equations based on intake. Key words: manure nitrogen excretion, prediction model, dairy cow
... For this reason, cows are the most inefficient organisms regarding nitrogen utilization. It has been found that between 50 and 80% of consumed nitrogen is excreted as urea and other nitrogen compounds through feces and urine [8] (a consequence of physiology and trophic position), which represent important sources of ammonia emissions [9]. Most of the nitrogen is present in the urine and a smaller part in the feces. ...
... However, it should be kept in mind that ammonia emissions from manure (urine) also depend on other factors. Research has shown that the type of soil, atmospheric humidity, temperature, wind speed or air currents in the shelter influence this aspect and cause large variations in ammonia losses from urine: between 25-50% [9] or between 4-52% [20]. In this regard, significant results were achieved [21] stating that ammonia emissions increase with temperature, and that this is directly related to the type of floor in the shelter and the management of manure. ...
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One of the major challenges of animal husbandry, in addition to those related to the economic situation and the current energy crisis, is the major contribution of this sector to atmospheric pollution. Awareness of pollution sources and their permanent monitoring in order to ensure efficient management of the farm, with the aim of reducing emissions, is a mandatory issue, both at the macro level of the economic sector and at the micro level, specifically at the level of each individual farm. In this context, the acquisition of consistent environmental data from the level of each farm will constitute a beneficial action both for the decision-making system of the farm and for the elaboration or adjustment of strategies at the national level. The current paper proposes a case study of air pollutants in a cattle farm for different seasons (winter and summer) and the correlation between their variation and microclimate parameters. A further comparison is made between values estimated using the EMEP (European Monitoring and Evaluation Programme, 2019) methodology for air pollutant emission and values measured by sensors in a hybrid decision support platform for farms. Results show that interactions between microclimate and pollutant emissions exist and they can provide a model for the farm’s activities that the farmer can manage according to the results of the measurements.
... In Europe, more than 90% of the anthropogenic ammonia emission originates from agriculture, where manure management and emission from soils are the two main contributors due to application of N fertilizer (Behera et al., 2013). One of the main factors affecting ammonia emission from cattle manure is the amount of N excreted in urine of which urea constitutes 50-90% (Hristov et al., 2011;Dijkstra et al., 2013). Urinary urea is rapidly hydrolyzed to form ammonia by the activity of urease, an enzyme produced by microbes present in feces. ...
... Urinary urea is rapidly hydrolyzed to form ammonia by the activity of urease, an enzyme produced by microbes present in feces. The volatilization rate depends on the ammonia concentration in the slurry, and the main part of the ammonia volatilization can therefore be attributed to urinary N, as N in feces primarily is organic bound and thus less volatile (Hristov et al., 2011;Behera et al., 2013). Intake of N has been stated to be the main driver for N excretion, especially in urine (Huhtanen et al., 2008;Dong et al., 2014), as consumption of N in excess of rumen microbiota and animal requirements are excreted in urine (Bockmann et al., 1997). ...
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The aim of this study was to examine the effect of age and dietary crude protein (CP) level on nitrogen (N) excretion in dairy heifers and to develop simple models to predict N excretion on farm based on nutrient intake parameters. Thirty-six Danish Holstein heifers were divided into 4 age groups; 8, 12, 16, and 20 months old (M8, M12, M16, and M20), respectively, with 9 animals per group. Heifers within age groups were blocked in groups of 3 according to age and pregnancy stage and were randomly assigned to dietary treatments in a 3 × 3 Latin square design. The dietary treatments consisted of 4 diets in total with CP concentrations of 9.8, 12.2, 14.6, and 17.0%, respectively, of which the 3 diets with the highest CP concentrations (i.e. 12.2, 14.6, and 17.0%) were provided to M8 and M12 heifers, and the 3 diets with the lowest CP concentrations (i.e. 9.8, 12.2, and 14.6%) were provided to M16 and M20 heifers. The experiment was divided into 3 periods, each period lasting for 2 weeks of which the first 11 days were used as adaptation and the last 3 days were used for sampling and recording. Feed and water intake were recorded daily, and feces (n = 6, pooled) and urine samples (n = 2, pooled) were collected and analyzed for chemical composition. Fecal output of N increased with increased dietary CP level, and this was probably due to the increase in dry matter intake (DMI) and N intake observed when increasing dietary CP level. Urinary N excretion increased with increased CP level in the diet, and was greatest in older heifers. Thus, for dairy heifers, urinary N output appeared to be strongly correlated with dietary N intake and seemed to increase with age. A dietary CP level of 12.2% seemed sufficient for heifers in all age groups to maintain adequate rumen microbial digestion, underpinning the potential of reducing urinary N by dietary manipulation. However, due to the short experimental periods, this study cannot state whether this CP level fulfills the N requirement for growth during the whole rearing period of dairy heifers. Furthermore, a simple prediction equation was established for N excretion in feces: N feces (g/d) = 0.054 × N intake + 6.52 × DMI and was considered a reliable proxy for N excretion in replacement heifers for application on farm.
... In addition, they lead to a significant loss of N, a valuable plant nutrient. Therefore, there is great interest in the application of control technologies to reduce NH 3 emissions through N capture and recovery, which would partially offset the implementation and operation costs associated with such control technologies through the revenue obtained from the sale of the fertilizer product [3,4]. ...
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The technology of gas-permeable tubular membranes (GPMs) is promising in reducing ammonia emissions from livestock manure, capturing NH3 in an acidic solution, and obtaining final products suitable for valorization as fertilizers, in line with the principles of the circular economy. This study aimed to evaluate the performance of several e-PTFE membrane systems with different configurations for the recovery of NH3 released from pig slurry. Ten different configurations were tested: only a submerged membrane, only a suspended membrane in the same chamber, only a suspended membrane in an annex chamber, a submerged membrane + a suspended membrane in the same chamber, and a submerged membrane + a suspended membrane in an annex chamber, considering in each case the scenarios without and with agitation and aeration of the slurry. In all tests, sulfuric acid (1N H2SO4) was used as the NH3 capture solution, which circulated at a flow rate of 2.1 L·h−1. The results showed that NH3-N removal rates ranged from 36-39% (for systems with a single submerged or suspended membrane without agitation or aeration of the slurry) to 70-72% for submerged + suspended GPM systems with agitation and aeration. In turn, NH3-N recovery rates were found to be between 44-54% (for systems with a single membrane suspended in an annex compartment) and 88-91% (for systems based on a single submerged membrane). However, when choosing a system for farm deployment, it is essential to consider not only the capture and recovery performance of the system, but also the investment and operating costs (ranging from 9.8 to 21.2 €/kg N recovered depending on the selected configuration). The overall assessment suggests that the simplest systems, based on a single membrane, may be the most recommendable.
... Immediately following excretion of urine and feces from the animal, NH 3 formation and volatilization occur rapidly due to abundant urease activity in the feces and soil (Bussink and Oenema, 1998), with manure N losses via volatilization ranging from 43 to 64% of fed N (Homolka et al., 2021). Seasonal differences in manure N loss via NH 3 volatilization occur due to the impacts of temperature and moisture conditions on feedlot pen surface microbial activity and the speed of chemical reactions with greater losses occurring during summer feeding periods (Gilbertson et al., 1971;Kissinger et al., 2007;Hristov et al., 2011;Homolka et al., 2021). Various feedlot management strategies, such as sawdust application (Lory et al., 2002) and increased dietary bran inclusion (Adams et al., 2004), have shown that as OM content is increased on the pen surface, greater N is retained in the manure and N losses via NH 3 volatilization are reduced. ...
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Feedstuffs utilized in U.S. feedlot finishing rations incorporate high concentrations of N and P, with less than 15% of fed N and P retained by the animal. The remaining N and P are excreted in the manure, where the opportunity for manure N loss via ammonia (NH3) volatilization from the feedlot pen surface is a risk to the environment and lowers the value of manure as a fertilizer. Two nutrient mass balance experiments were conducted during winter and summer seasons to evaluate the effects of spreading unprocessed Eastern red cedar biochar onto the feedlot pen surface on manure nutrient capture and cattle performance. A 186-d feedlot finishing experiment was conducted from December to June (WINTER) and a subsequent 153-d finishing experiment was conducted from June to November (SUMMER). The WINTER experiment evaluated three treatments (5 pens per treatment; 10 steers per pen), including biochar spread on pen surface during the feeding period (1.40 kg biochar/m 2; 17.6 m 2/steer soil surface of pen), hydrated lime spread on pen surface at end of feeding period (1.75 kg/m 2) and control (no treatment applied). The SUMMER experiment evaluated biochar treatment (1.40 kg biochar/m 2; 5 pens per treatment; 8 steers per pen; 22 m 2/steer soil surface of pen) against control. There were no differences in N and P intake, retention, or excretion (P ≥ 0.38) between WINTER treatments. Steer performance (P ≥ 0.10) and carcass characteristics (P ≥ 0.50) were not impacted by pen treatment in WINTER. Nitrogen and P intake and excretion (P ≥ 0.35) were not different between treatments in SUMMER and retention of N and P was significantly greater for the biochar treatment (P ≤0.04) due to greater ADG (P = 0.05). There was no difference in DMI (P = 0.48) in SUMMER, steers on biochar pen treatment had heavier HCW (P = 0.05) and greater ADG, resulting in a tendency for greater feed efficiency (P = 0.08). In both experiments, biochar addition to the pen surface tended (P = 0.07) to increase manure N as a percent of manure DM, but this increase in N concentration did not impact kg of N removed from the feedlot pens (P ≥ 0.15) or N losses (P ≥ 0.68). The addition of red cedar biochar to the feedlot pen surface did not increase manure nutrient capture of N or P and did not reduce N losses associated with soil-based feedlot pens.
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The Winter Fog Experiment (WiFEX) was an intensive field campaign conducted at Indira Gandhi International Airport (IGIA) Delhi, India, in the Indo-Gangetic Plain (IGP) during the winter of 2017–2018. Here, we report the first comparison in South Asia of high-temporal-resolution simulation of ammonia (NH3) along with ammonium (NH4+) and total NHx (i.e., NH3+ NH4+) using the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) and measurements made using the Monitor for AeRosols and Gases in Ambient Air (MARGA) at the WiFEX research site. In the present study, we incorporated the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) aerosol scheme into WRF-Chem. Despite simulated total NHx values and variability often agreeing well with the observations, the model frequently simulated higher NH3 and lower NH4+ concentrations than the observations. Under the winter conditions of high relative humidity (RH) in Delhi, hydrogen chloride (HCl) was found to promote the increase in the particle fraction of NH4+ (which accounted for 49.5 % of the resolved aerosol in equivalent units), with chloride (Cl−) (29.7 %) as the primary anion. By contrast, the absence of chloride (HCl / Cl−) chemistry in the standard WRF-Chem model results in the prediction of sulfate (SO42-) as the dominant inorganic aerosol anion. To understand the mismatch associated with the fraction of NHx in the particulate phase (NH4+ / NHx), we added HCl / Cl− to the model and evaluated the influence of its chemistry by conducting three sensitivity experiments using the model: no HCl, base case HCl (using a published waste burning inventory), and 3 × base HCl run. We found that 3 × base HCl increased the simulated average NH4+ by 13.1 µg m−3 and NHx by 9.8 µg m−3 concentration while reducing the average NH3 by 3.2 µg m−3, which is more in accord with the measurements. Thus HCl / Cl− chemistry in the model increases total NHx concentration, which was further demonstrated by reducing NH3 emissions by a factor of 3 (−3 × NH3_EMI) in the 3 × base HCl simulation. Reducing NH3 emissions in the 3 × base HCl simulation successfully addressed the discrepancy between measured and modeled total NHx. We conclude that modeling the fate of NH3 in Delhi requires a correct chemistry mechanism accounting for chloride dynamics with accurate inventories of both NH3 and HCl emissions.
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The population of feeder cattle in feedlots is not significant compared to the total cattle population. However, the intensive management system in feedlots has negative impact on the environment. Currently, there is limited information on manure handling in the beef cattle feedlots in Indonesia. This study aimed to describe the manure management system of surveyed feedlots in Lampung Province, Indonesia. The method of this study was descriptive with field observation and survey in three feedlots in Lampung. Data related to manure management were collected on the farm, while the data on manure management systems, animal characteristics, and housing system were gathered from questionnaires in the survey. The data were described and analysed using comparison with previous studies. The result showed that the surveyed feedlots utilize manure as organic fertilizer. The manure and effluent were treated and pumped onto forage fields. One feedlot company with an advanced manure treatment facility has implemented a sustainable manure management strategy. The study suggests further research to measure the carbon cycle for several types of feedlot’s manure management systems as an environmental product declares of beef cattle production in Indonesia.
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Dairy concentrated animal feeding operations (CAFOs) are significant sources of methane (CH4) and ammonia (NH3) emissions in the San Joaquin Valley, California. Optical techniques, namely, remote sensing by Solar Occultation Flux (SOF) and Mobile extractive FTIR (MeFTIR), were used to measure NH3 air column and ground air concentrations of NH3 and CH4, respectively. Campaigns were performed in May and October 2019 and covered 14 dairies located near Bakersfield and Tulare, California. NH3 and CH4 emission rates from single CAFOs averaged 101.9 ± 40.6 kgNH3/h and 437.7 ± 202.0 kgCH4/h, respectively, corresponding to emission factors (EFs) per livestock unit of 9.1 ± 2.7 gNH3/LU/h and 40.1 ± 17.8 gCH4/LU/h. The NH3 emissions had a median standard uncertainty of 17% and an expanded uncertainty (95% Confidence Interval (CI)) of 37%; meanwhile, CH4 emissions estimates had greater uncertainty, median of 25% and 53% (in the 95% CI). Decreasing NH3 to CH4 ratios and NH3 EFs from early afternoon (13:00) to early night (19:00) indicated a diurnal emission pattern with lower ammonia emissions during the night. On average, measured ammonia emissions were 28% higher when compared to daytime emission rates reported in the National Emissions Inventory (NEI) and modeled according to diurnal variation. Measured CH4 emissions were 60% higher than the rates reported in the California Air Resources Board (CARB) inventory. However, comparison with airborne measurements showed similar emission rates. This study demonstrates new air measurement methods, which can be used to quantify emissions over large areas with high spatial resolution and in a relatively short time period. These techniques bridge the gap between satellites and CAFOs measurements.
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Advances in amino acid metabolism and nutrition in farm and companion animals are discussed. Separate chapters are given to the different farm animal species (such as pigs, poultry and ruminants) and companion animals (dogs and cats). This book was written as a reference material for advanced students and researchers in animal nutrition.
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Global simulations of sulfate, nitrate, and ammonium aerosols are performed for the present day and 2050 using the chemical transport model GEOS-Chem. Changes in climate and emissions projected by the IPCC A1B scenario are imposed separately and together, with the primary focus of the work on future inorganic aerosol levels over the United States. Climate change alone is predicted to lead to decreases in levels of sulfate and ammonium in the southeast U.S. but increases in the Midwest and northeast U.S. Nitrate concentrations are projected to decrease across the U.S. as a result of climate change alone. In the U.S., climate change alone can cause changes in annually averaged sulfate-nitrate-ammonium of up to 0.61 μg/m^3, with seasonal changes often being much larger in magnitude. When changes in anthropogenic emissions are considered (with or without changes in climate), domestic sulfate concentrations are projected to decrease because of sulfur dioxide emission reductions, and nitrate concentrations are predicted to generally increase because of higher ammonia emissions combined with decreases in sulfate despite reductions in emissions of nitrogen oxides. The ammonium burden is projected to increase from 0.24 to 0.36 Tg, and the sulfate burden to increase from 0.28 to 0.40 Tg S as a result of globally higher ammonia and sulfate emissions in the future. The global nitrate burden is predicted to remain essentially constant at 0.35 Tg, with changes in both emissions and climate as a result of the competing effects of higher precursor emissions and increased temperature.