The influence of using different types of modified vermiculite cover on ammonia mitigation from animal slurry storage: The role of sulfuric acid.

Animal slurry storage is an important ammonia (NH3) emission source. Sulfuric acid (H2SO4)-modified vermiculite coverage is a new promising technology for controlling NH3 emission from slurry storage. However, the underlying mechanisms in controlling the mitigation effect remain unclear. Here, a series of experiments to determine the effect of H2SO4 on the modified vermiculite properties, floating persistence, and NH3 mitigation effect was conducted. Results showed that abundant H2SO4 and sulfate remained on the outer surface and in the extended inner pores of the vermiculite with acidifying H+ concentrations higher than 5 M. An initial strong instantaneous acidification of surface slurry released rich carbon dioxide bubbles, strengthening cover floating performance. An acidification in the vermiculite cover layer and a good coverage inhibition interacted, being the two leading mechanisms for mitigating NH3 during initial 40-50 days of storage. The bacterial-amoA gene dominated the conversion of NH3 to nitrous oxide after 50 days of storage. Vermiculite with 5 M H+ modification reduced the NH3 emissions by 90 % within the first month of slurry storage and achieved a 64 % mitigation efficiency throughout the 84 days period. With the development of the aerial spraying equipment such as agricultural drones, acidifying vermiculite coverage hold promise as an effective method for reducing NH3 emission while absorbing nutrients from liquid slurry storage tank or lagoon. This design should now be tested under field conditions.

Hydrogen production promotion and energy saving in anaerobic co-fermentation of heat-treated sludge and food waste.

The objective of this paper is to gain insights into the synergistic advantage of anaerobic co-fermentation of heat-treated sludge (HS) with food waste (FW) and heat-treated food waste (HFW) for hydrogen production. The results showed that, compared with raw sludge (RS) mixed with FW (RS-FW), the co-substrate of HS mixed with either FW (HS-FW) or HFW (HS-HFW) effectively promoted hydrogen production, with HS-HFW promoted more than HS-FW. The maximum specific hydrogen production (MSHP) and the maximum hydrogen concentration (MHC) of HS-HFW were 40.53 mL H2/g dry weight and 57.22%, respectively, and 1.21- and 1.45-fold as high as those from HS-FW. The corresponding fermentation was ethanol type for HS-HFW and butyric acid type for HS-FW. The net energy production from RS-FW and HS-FW was both negative, but it was positive (2.57 MJ) from 40% HFW addition to HS-HFW. Anaerobic fermentation was more viable for HS-HFW.

Identified factors and predicted unidentified-factors affecting ammonia emissions from a swine building.

Large variabilities in ammonia (NH3) released from animal manure and emitted from different livestock buildings were frequently reported, but the factors influencing the emissions were not sufficiently investigated. In this paper, continuously monitored data of NH3 emissions and other relevant environmental variables under controlled conditions in a 12-room experimental swine building for a 155-d complete wean-to-finish cycle were studied. Measurement data mining was conducted at both spatial and temporal dimensions using panel data analysis with heterogeneous time trends. The pig diet, total pig weight, and the pit air temperature were identified as the major influencing factors for the variabilities by using multivariate linear regression. Two unidentified factors that imposed substantial influences on the NH3 emission variabilities were predicted. They were most possibly related to variations in microenvironment and microbial activity inside the manure in the pit. The results suggest necessary future research to identify physical properties of the new NH3 emissions factors in microbiological and biochemical processes.

Computational Fluid Dynamics Modeling of a Broiler House Microclimate in Summer and Winter.

Appropriate microclimate conditions in broiler housing are critical for optimizing poultry production and ensuring the health and welfare of the birds. In this study, spatial variabilities of the microclimate in summer and winter seasons in a mechanically ventilated broiler house were modeled using the computational fluid dynamics (CFD) technique. Field measurements of temperature, relative humidity, and airspeeds were conducted in the house to compare the simulated results. The study identified two problems of high temperature in summer, which could result in bird heat stress and stagnant zones in winter, and simulated possible alternative solutions. In summer, if an evaporative cooling pad system was used, a decrease in temperature of approximately 3 °C could be achieved when the mean air temperature rose above 25 °C in the house. In winter, adding four 500-mm circulation fans of 20-m spacing inside the house could eliminate the accumulation of hot and humid air in the stagnant zones in the house. This study demonstrated that CFD is a valuable tool for adequate heating, ventilation, and air conditioning system design in poultry buildings.

The effect of reduced CP, synthetic amino acid supplemented diets on growth performance and nutrient excretion in wean to Finish swine.

Mixed sex pigs (n = 720) were placed in 12 rooms (Purdue Swine Environmental Research Building) to measure the effect of reduced crude protein (CP), amino acid (AA)-supplemented diets on growth and the carcass. Pigs were blocked by body weight (BW) and gender and allotted to room and pen (10 mixed-sex pigs/pen). Pigs were fed a nine-phase, wean-finish program. Control pigs consumed corn-soybean meal-distiller's dried grains with solubles (DDGS) diets containing no to minimal (Met) synthetic AA. The 2X diet was formulated to meet the seventh most-limiting AA, and balanced using synthetic AAs to meet all AA needs. The 1X diet was formulated to meet a CP value halfway between the control and 2X diet, and also balanced using synthetic AAs to meet all AA needs. Diets were formulated to identical net energy concentrations and balanced to meet standard ileal digestible NRC 2012 AA requirements. Pit vacuum samples were collected at the end of each growth phase for analyses of nitrogen, C and dry matter (DM). Pigs fed the Control and 1X diet grew faster (P < 0.005), had greater gain:feed (P < 0.001), and were heavier at market (P < 0.001) than animals fed the 2X diet. No consistent effects of diet were observed on average daily feed intake. Carcass data were analyzed for sex, diet and sex*diet effects. Reductions in dietary CP resulted in a linear reduction in ammonium nitrogen excretion per kg of BW gain in Nursery (P < 0.001) and Grow-Finish (P < 0.001) phases. Reductions in dietary CP, with synthetic AA supplementation resulted in a linear reduction in total nitrogen excreted per kg BW gain in the Grow-Finish phase (P < 0.001) and overall (P < 0.001). Total mineral excretion per kg gain was reduced in pigs fed 1X and 2X diets compared with control-fed pigs (P < 0.005). Reductions in dietary CP of ~3 and 5%-units from wean-finish result in reductions of total N excretion of 11.7 and 24.4%, respectively. Reduced performance and carcass characteristics observed in pigs fed the 2X diets indicates an inaccurate estimate of NRC 2012 AA requirements or ratios to lysine in a low CP diet.

Summary of Known U.S. Injuries and Fatalities Involving Livestock Waste Storage, Handling, and Transport Operations: 1975-2019.

HIGHLIGHTS: Approximately ten cases were documented annually over the 44-year period; 48% were in the last decade and 28% were in the last three years, primarily due to more aggressive surveillance and on-line access to incident reports. A total of 389 incidents involving 459 individuals were documented, of which 59% were fatal; >85% of the victims were male, with an average age of 37. 49 rescue incidents involved a total of 119 secondary victims, indicating that approximately 26% of the victims were secondary victims, including first responders. 20% of all victims, when age was known, were children or youth under the age of 21. ABSTRACT: There is limited published research exploring the frequency and causes of livestock waste-related fatalities and injuries among farm operators and workers. While there has been ongoing surveillance of mortality and morbidity involving agricultural confined space-related incidents, such as grain storage facilities, few resources have been invested in estimating the frequency of livestock waste-related incidents, which are often reported as primarily involving confined spaces. Existing surveillance efforts have historically underreported fatal cases, injuries, and near misses and misclassified these incidents as non-farm related. For nearly 40 years, the Purdue Agricultural Confined Spaces Incident Database (PACSID) has been used to document agricultural confined space-related incidents, of which manure storage and handling activities have accounted for 22% of the cases documented. The specific goal of this study was to address the gap in the current understanding of the frequency and severity of injuries associated with livestock waste storage, handling, and transport by: (1) developing a consistent way to identify, document, and code these cases; (2) summarizing all known U.S. cases, both fatal and non-fatal, currently documented in the PACSID; (3) identifying the most significant risks contributing to livestock waste storage, handling, and transport-related incidents; and (4) providing evidence-based recommendations and mitigation strategies to enhance the effectiveness of current injury prevention measures. The PACSID and other sources were mined for relevant data, and an aggressive effort was made to document additional cases through a variety of surveillance methods. A total of 459 individual U.S. cases from the study period (1975 to 2019) were identified, coded using a uniform coding system, and summarized. Overall, cases were documented in 43 states, with 66% (302 cases) documented in heavily agricultural and, more specifically, historically strong dairy production states. Of the cases reviewed, 59% were fatal, males ages 21 to 30 and dairy farm workers were identified as high-risk populations, 20% were identified as under the age of 21, and 49 incidents involved multiple victims. Farm injury data limitations and underreporting were problematic, especially during the early years of the study period. However, the findings provide a foundation for recommending safer workplace safety and health practices, evaluating existing engineering and regulatory standards, assessing the impacts of current injury prevention efforts, and redesigning farm safety programs, especially those targeting livestock workers, to reduce the frequency and severity of these incidents.

Long-term performance of three mesophilic anaerobic digesters to convert animal and agro-industrial wastes into organic fertilizer.

Few studies have investigated the performance of anaerobic digestion (AD) to convert animal and agro-industrial wastes to organic fertilizers over a long-term field conditions. This paper studied three large-scale mesophilic digesters (D1eD3) over two years for their effects on feedstocks, which were dairy manure for D1 and D2 and co-digestion mixed manure and agro-industrial wastes for D3. Hydraulic retention times (HRT) were 9 d for D1, 12 d for D2, and 34 d for D3. Digester influent and effluent samples were taken every two months from the digesters and analyzed for pH, and concentrations of total solids (TS), ammonium nitrogen (NH4-N), total Kjeldahl nitrogen (TKN), total phosphorus (TP), and eight metals. The study revealed high variability in converting feedstock in the three digesters. Compared with their respective influent, the mean digester effluent pH decreased from 7.9 by 0.6 in D1 (p < 0.01) and by 0.3 in D2 (p < 0.01), but it increased from 6.1 by 1.8 in D3 (p < 0.01). The mean digester effluent TS increased from 3.4% by 0.1% (p > 0.05) in D1, but it decreased from 4.9% by 1.3% in D2 (p < 0.05) and from 12.3% by 4.8% in D3 (p < 0.01). All three digesters significantly increased NH4-N concentrations by 21.4 e81.8% (p < 0.05), but insignificantly changed TKN and TP concentrations (p > 0.05). Effects of AD on all metal concentrations were mixed and were insignificant (p > 0.05) because of large concentration variations. However, study of a ratio quotient (q Mg ) using magnesium (Mg) as the reference discovered accumulation of NH4-N, copper, potassium, and sodium, but loss of TKN, TP, iron, manganese, zinc, and calcium during AD for D2 and D3. The impact of AD conversion was closely related with types of feedstock (on pH) and HRT (on TS and NH4-N). The results of this study can assist in developing strategies for cleaner production using AD in an environmentally sustainable manner.

Summary of Injuries and Fatalities Involving Livestock Manure Storage, Handling, and Transport Operations in Seven Central States: 1976-2019.

HIGHLIGHTS A total of 133 cases were documented in a seven-state region, with Iowa reporting 43% of the cases and asphyxiations accounting for 42% of all cases. Most victims were male (>79%) with an average age of 38 years. The overall fatality rate was 57%, and 16% of the victims were under the age of 21. Thirteen incidents involved secondary victims, including eleven incidents involving two, one incident involving three, and one incident involving four. ABSTRACT. Research was conducted to document, classify, analyze, and summarize available injury and fatality data involving facilities and equipment for livestock manure storage, handling, and transport in the seven-state region (Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota) served by the Central States Center for Agricultural Safety and Health (CS-CASH). Data were initially drawn from the Purdue Agricultural Confined Space Incident Database (PACSID), which contained over 2,400 individual U.S. cases of agricultural confined space related entrapment, engulfment, entanglement, asphyxiation, and falls that were documented between 1975 and 2019. Data from these cases have been partially summarized and published, but the findings did not include in-depth analysis of manure-related incidents. Approximately one in five (460) of the 2,400+ cases that were documented over 44 years involved storage, handling, or transport of livestock wastes, including exposure to toxic gases. Of these, 133 cases were documented as having occurred in the targeted seven-state region. Each case was identified and coded according to a protocol developed previously to classify incidents related to livestock manure handling, storage, and transport. Iowa and Minnesota accounted for 79% of the total, with swine operations accounting for 33% of cases when livestock type was known. Of the victims, 79% were male. Ages ranged from 1 to 85, with an average age of 38, and 15% of the victims were age 21 and under. There were 13 incidents for which two or more victims were identified, including one incident involving four victims. It is believed that historical under-reporting of incidents, especially non-fatal incidents, continues to be a barrier to achieving a more comprehensive understanding of the scope and magnitude of the problem. However, the findings are sufficient to be used in cooperation with stakeholders to enhance the content and delivery of evidence-based agricultural safety and health programs, promote safer work practices, and contribute to the development of engineering design standards. The desired outcomes of this research include more effective strategies to protect farmers and farm workers who are at high risk of manure-related injuries. The findings also provide a sufficient baseline to gauge the effectiveness of future injury prevention measures.

Dynamic and 3-D spatial variations in manure characteristics in two commercial manure-belt laying hen houses.

Animal manure could be hazardous to human and animals if not managed properly. Laying hen manure in two commercial manure-belt houses was sampled in seven events over two years. A total of 124 samples was taken in randomly-selected 3-D space with 24 subspaces, composed of 3 sections × 4 sides × 2 floors in the houses. The samples were analyzed for manure pH, total solids (TS), and total ammonia (NH3). Manure characteristics demonstrated large temporal variations that were correlated with indoor temperature and ventilation rate and demonstrated quasi seasonal patterns. Variations in manure NH3 were larger than TS and pH. Manure characteristics varied substantially in the 3-D space but no patterns could be seen among the four sides and between the two floors. However, manure with different ages in the 3 sections along the manure belt moving direction showed differences in manure TS and NH3. Manure on the belts could loss approximately 2.5 % moisture and 0.2 % NH3 concentration per day.

Farm-Related Injuries and Fatalities Involving Children, Youth, and Young Workers during Manure Storage, Handling, and Transport.

Objective: Manure storage, handling, and transport facilities and equipment have been associated with life threatening hazards on many livestock farms. These hazards have been documented in prior research as including 1) exposure to toxic manure gases or lack of adequate oxygen in enclosed structures, which can be fatal to both humans and livestock; 2) below and above ground liquid manure storage structures that have the potential risk for drowning and falling; and 3) mechanical hazards associated with manure handling and transport equipment, including entanglement, road collisions, runover, and equipment failure.Methods: Over the past 40 years, Purdue University's Agricultural Safety and Health Program (PUASHP) has collected, documented, and maintained data regarding agricultural-related injuries and fatalities associated with agricultural confined spaces in the United States. As part of ongoing surveillance, a total of 369 fatal and non-fatal cases relating to manure storage, handling and transport equipment, and facilities have been documented. Of these, 89 have involved children, youth, and young farm workers ages (birth-21) documented between 1975 and 2019. The purpose of this study was to summarize these 89 documented cases to better understand contributing factors and to develop recommendations for evidence-based strategies to reduce the frequency and severity of these incidents. Though recognized as not comprehensive for all incidents of this type, the data represent the largest data set known to exist, providing insight into previously unstudied hazards facing children and youth living and working on, and visiting farms as non-workers.Results: Findings in this study include: there has been an increase in the documented frequency of these incidents, which may be due, at least partially, to enhanced or more aggressive surveillance efforts; 57% of the cases were fatal; incidents involving underground or inground manure storage facilities were the most frequent type; incidents involving manure transport vehicles were higher than expected; 33% of the victims were five years of age and younger; and July was the month with the most documented incidents.Conclusions: Recommendations for future injury prevention strategies include incorporation of information on manure-related hazards in curricula targeting children and youth, more aggressive enforcement of child labor laws that currently prohibit the employment of youth to work in manure storage structures or to be involved in their operations, and greater use of physical and administrative controls, including safety signage, fencing, gates, and covers to restrict access to manure storage structures.

A critical review of advancement in scientific research on food animal welfare-related air pollution.

Air pollution generates hazardous pollutants that have resulted in safety, health, and other welfare issues of food animals. This paper reviewed scientific research advancement in food animal welfare-related air pollution based on 219 first-hand research publications in refereed journals (referred to as "RPs") over the past nine decades. Scientific studies in this area began in the 1930s. The number of RPs has increased significantly with each decade from the 1960s to the 1980s, then decreased until the 2010s. Twenty-six countries have contributed to this multidisciplinary research. About 52% of the studies were conducted in the U.S. and U.K. Research activities have surged in China since the 2010s. On-farm discoveries in air toxicity that resulted in animal death or injury were all from observational studies. About 75% of the studies were experimental and conducted primarily under laboratory conditions. Ammonia (NH3) was the main pollutant in 59% of the RPs, followed by dust, hydrogen sulfide (H2S), bacteria and endotoxins, carbon dioxide (CO2), carbon monoxide (CO), silo gas, sulfur dioxide (SO2), and odor. Approximately 23% of RPs reported multiple pollutants in the same study. The most intensively studied animal species were poultry (broilers, hens, turkeys, ducks, and eggs and embryos in 44% of the RPs) and pigs (also 44%), followed by cattle, and sheep and goats. Scientific investigations in this area were driven by the research focuses in the areas of animal agriculture and industrial air pollution. Some major research teams played important roles in advancing scientific research. However, research in this area is still relatively limited. There is a great need to overcome some technical challenges and reverse the trend of decreasing research activities in North America and Europe.

New insights into concentrations, sources and transformations of NH3, NOx, SO2 and PM at a commercial manure-belt layer house.

Pollutant gases and particulate matters (PM) from livestock facilities can affect the health of animals and farm workers and lead to great social environmental risks. This paper presents a comprehensive study on the characteristics of ammonia (NH3), nitrogen oxides (NOx), sulfur dioxide (SO2) and PM (including PM2.5 and PM10) in a 100,000-bird manure-belt layer house in suburb Beijing for three typical seasons of summer, autumn and winter. Indoor air was sampled at an exhaust fan of the mechanically ventilated commercial house. The monitored indoor concentrations of NH3, NOx, SO2, PM2.5 and PM10 were 3.7-5.0 mg m-3, 17-58 µg m-3, 0-11 µg m-3, 100-149 µg m-3 and 354-828 µg m-3, respectively. The indoor NH3 concentrations were largely influenced by the manure removal frequency. The NOx and SO2 were mainly sourced from the ambient air, and the NOx was also partly sourced from manure decomposition in summer. The indoor PM2.5 and PM10 were largely sourced from the ambient air and the indoor manure, respectively. The abundant indoor NH3 caused significantly higher NH4+ concentration in the indoor PM10 (7.98 ± 9.04 µg m-3) than that in the ambient PM10 (3.48 ± 3.52 µg m-3). Secondary inorganic ions (SO42-, NO3- and NH4+) totally contributed 5.7% and 14.6% to the indoor and ambient PM2.5, respectively; they contributed 2.8% and 8.9% to the indoor and ambient PM10, respectively. Organic carbon was the main component of the PM and accounted for 26.6% and 41.5% of the indoor PM2.5 and PM10, respectively. Heavy metal elements (Zn, Cu and Cr) were likely transported from feed to manure and finally accumulated in the PM. Given the high emission potential, the air pollutants from animal production suggested potential risks for human health.

Effects of antibiotic-free pig rearing on ammonia emissions from five pairs of swine rooms in a wean-to-finish experiment.

Antibiotic use and ammonia (NH3) emissions during animal production are two environmental issues of worldwide concern. However, the role of antibiotics on NH3 emissions is still unknown. This study evaluated the effects of rearing pigs without antibiotics on NH3 emissions from a swine experimental building starting with 657 piglets during a wean-to-finish production cycle of 154 days. Pigs were reared in two groups of 10 rooms that were divided into five 2-room pairs (P1-P5) and fed in nine dietary phases. Each pair consisted of one room without antibiotics (no antibiotics in the diet, water, or injectable) and another room as a positive control. Control animals were fed diets containing carbadox-10 (phases 1-4), chlortetracycline (CTC, phase 5), lincomix (phases 6-7), and tylan 40 (phases 8-9). Temperatures in the pig living space and the under-floor manure pit headspace were continuously measured. Ventilation rates at all wall fans and pit fans were obtained by continuous monitoring. Ammonia concentrations in the wall and pit fan exhaust air, and in room inlet air were measured with two multi-gas monitors. Only days that contained at least 18 h of data each day were validated and used. The study generated 1337 room-days of valid data of NH3 emission rates, with a data completeness of 88.6%. Daily mean NH3 emission patterns demonstrated large variations between the paired rooms and among different pairs. Within the individual 2-room pairs, no NH3 emission differences were found in P1 (rooms 1 and 2, p = 0.34) and P2 (rooms 3 and 4, p = 0.44). Significant differences were found in P3-P5 (p < 0.01). The antibiotic-free rooms emitted more NH3 from P3 and P4, but less NH3 from P5. However, the combined cycle mean NH3 emissions from the group of five antibiotic-free rooms and the group of five control rooms were 41.6 ±â€¯10.5 and 39.4 ±â€¯10.6 g d-1 AU-1 (mean ±â€¯standard deviation. AU = 500 kg live body weight), respectively. Therefore, there was no statistical difference in combined cycle mean NH3 emissions from rearing pigs with or without antibiotics (p = 0.78). This study also revealed that experiments with multiple replicates and long NH3 monitoring durations were necessary to avoid potential misinterpretation of experimental results.

Development of methodology to document and code farm-related injuries and fatalities involving manure storage, handling and transport - with summary of 2017 incidents.

As part of ongoing surveillance of fatalities and injuries involving agricultural confined spaces by Purdue University's Agricultural Safety and Health Program, nearly 300 cases involving manure storage, handling, and transport equipment and facilities have been documented over the past 30 years. With the exception of a summary of 77 fatalities published by Beaver and Field1, these cases have not been previously analysed or published due to a lack of resources and the limitations of the Purdue Agricultural Confined Spaces Incident Database (PACSID) which was designed primarily for analysis of grain-related cases. These limitations included differences in terminology used to code case information in the PACSID and dissimilar causative and contributing factors. To develop a consistent and more useful approach to process and analyze data, 28 U.S. manure-related incidents involving 39 victims documented as having occurred in 2017 were examined for type of incident, victim characteristics, primary contributing factors, and nature of injuries. A review of literature was conducted to identify previously reported contributing factors, and a coding rubric was developed and reviewed by a panel of experts. It was determined that the rubric provided a consistent way to code and analyze descriptive information available on each case. A pilot analysis was completed of the 39 cases using the new tool, and results were summarized. The final methodology will be used to analyze all historically documented incidents, as well as future incidents. Findings presented include a review of relevant literature, discussion of the methods used in case documentation, classifications developed from sample data, and a summary of incidents in 2017. Anticipated outcomes include: 1) consistent strategy to document, code, and summarize manure-related incidents; 2) means of classification of key contributing factors; 3) identification of new or emerging trends; and 4) completion of previously documented incidents.

Hydrogen sulfide emissions from a swine building affected by dietary crude protein.

Hydrogen sulfide (H2S) is a toxic air pollutant at animal facilities; but the understanding of its generation and emission processes has been limited. This paper studied H2S emissions during a complete cycle of wean-finish pigs from a research building, where 12 pig rooms were divided into three groups that were fed with standard feed (control), and 2.1-3.8% (T1) and 4.4-7.8% (T2) reduced dietary crude protein (CP) feed. The group cycle mean H2S emission rates were 4.0 ± 2.9, 4.3 ± 3.2, and 5.4 ± 4.0 g d-1 AU-1 (Animal Unit = 500 kg live mass), respectively, for the control, T1, and T2 groups. Emissions of H2S were promoted by 10.0 and 36.7%, respectively, for the T1 and T2 groups (p < 0.001), although large variabilities existed in the emissions from different rooms within the same groups. The enhanced H2S emissions from the T1 and T2 groups were related to the reduced manure pH and were possibly affected through a number of pathways, which could involve volatile fatty acids and nitrogen concentrations, and microbial activities in manure.

Fuzzy comprehensive evaluation of multiple environmental factors for swine building assessment and control.

In confined swine buildings, temperature, humidity, and air quality are all important for animal health and productivity. However, the current swine building environmental control is only based on temperature; and evaluation and control methods based on multiple environmental factors are needed. In this paper, fuzzy comprehensive evaluation (FCE) theory was adopted for multi-factor assessment of environmental quality in two commercial swine buildings using real measurement data. An assessment index system and membership functions were established; and predetermined weights were given using analytic hierarchy process (AHP) combined with knowledge of experts. The results show that multi-factors such as temperature, humidity, and concentrations of ammonia (NH3), carbon dioxide (CO2), and hydrogen sulfide (H2S) can be successfully integrated in FCE for swine building environment assessment. The FCE method has a high correlation coefficient of 0.737 compared with the method of single-factor evaluation (SFE). The FCE method can significantly increase the sensitivity and perform an effective and integrative assessment. It can be used as part of environmental controlling and warning systems for swine building environment management to improve swine production and welfare.

Mitigation of ammonia emissions from pig production using reduced dietary crude protein with amino acid supplementation.

To mitigate ammonia (NH3) emissions from pig production and understand dynamic emission profiles, reduced dietary crude protein (CP) with amino acid supplementation was studied with 720 pigs in a 12-room research building for 155days that covered from weaned to finishing stages. The pigs were divided into three 4-room groups and fed with 2.1-3.8% reduced CP (T1), 4.4-7.8% reduced CP (T2), and standard (control) diets, respectively. Compared with the control group, T1 and T2 decreased manure volumes and manure NH4+-N concentrations. Group-mean NH3 emission from the control group was 68.9gd-1AU-1 (AU=500kg live mass). Emissions from T1 (46.7gd-1AU-1) and T2 (29.8gd-1AU-1) were reduced by 33.0% and 57.2% (p<0.05), respectively. Dynamic peak NH3 emissions appeared during the third nursery phase for T1 and T2, but delayed to the first grower phase for the control group.

A prediction model of ammonia emission from a fattening pig room based on the indoor concentration using adaptive neuro fuzzy inference system.

Ammonia (NH3) is considered one of the significant pollutions contributor to indoor air quality and odor gas emission from swine house because of the negative impact on the health of pigs, the workers and local environment. Prediction models could provide a reasonable way for pig industries and environment regulatory to determine environment control strategies and give an effective method to evaluate the air quality. The adaptive neuro fuzzy inference system (ANFIS) simulates human's vague thinking manner to solve the ambiguity and nonlinear problems which are difficult to be processed by conventional mathematics. Five kinds of membership functions were used to build a well fitted ANFIS prediction model. It was shown that the prediction model with "Gbell" membership function had the best capabilities among those five kinds of membership functions, and it had the best performances compared with backpropagation (BP) neuro network model and multiple linear regression model (MLRM) both in wintertime and summertime, the smallest value of mean square error (MSE), mean absolute percentage error (MAPE) and standard deviation (SD) are 0.002 and 0.0047, 31.1599 and 23.6816, 0.0564 and 0.0802, respectively, and the largest coefficients of determination (R2) are 0.6351 and 0.6483, repectively. The ANFIS prediction model could be served as a beneficial strategy for the environment control system that has input parameters with highly fluctuating, complexity, and non-linear relationship.

Characteristics of pollutant gas releases from swine, dairy, beef, and layer manure, and municipal wastewater.

Knowledge about characteristics of gas releases from various types of organic wastes can assist in developing gas pollution reduction technologies and establishing environmental regulations. Five different organic wastes, i.e., four types of animal manure (swine, beef, dairy, and layer hen) and municipal wastewater, were studied for their characteristics of ammonia (NH3), carbon dioxide (CO2), hydrogen sulfide (H2S), and sulfur dioxide (SO2) releases for 38 or 43 days in reactors under laboratory conditions. Weekly waste additions and continuous reactor headspace ventilation were supplied to simulate waste storage conditions. Results demonstrated that among the five waste types, layer hen manure and municipal wastewater had the highest and lowest NH3 release potentials, respectively. Layer manure had the highest and dairy manure had the lowest CO2 release potentials. Dairy manure and layer manure had the highest and lowest H2S release potentials, respectively. Beef manure and layer manure had the highest and lowest SO2 releases, respectively. The physicochemical characteristics of the different types of wastes, especially the total nitrogen, total ammoniacal nitrogen, dry matter, and pH, had strong influence on the releases of the four gases. Even for the same type of waste, the variation in physicochemical characteristics affected the gas releases remarkably.

Research and demonstration to improve air quality for the U.S. animal feeding operations in the 21st century - a critical review.

There was an increasing interest in reducing production and emission of air pollutants to improve air quality for animal feeding operations (AFOs) in the U.S. in the 21st century. Research was focused on identification, quantification, characterization, and modeling of air pollutions; effects of emissions; and methodologies and technologies for scientific research and pollution control. Mitigation effects were on pre-excretion, pre-release, pre-emission, and post-emission. More emphasis was given on reducing pollutant emissions than improving indoor air quality. Research and demonstrations were generally continuation and improvement of previous efforts. Most demonstrated technologies were still in a limited scale of application. Future efforts are needed in many fundamental and applied research areas. Advancement in instrumentation, computer technology, and biological sciences and genetic engineering is critical to bring major changes in this area. Development in research and demonstration will depend on the actual political, economic, and environmental situations.