Effectiveness and diurnal variations of vegetative environmental buffers (VEBs) for mitigating NH3 and PM emissions from poultry houses

Air pollutants from poultry production, such as ammonia (NH3) and particulate matter (PM), have raised concerns due to their potential negative impacts on human health and the environment. Vegetative environmental buffers (VEBs), consisting of trees and/or grasses planted around poultry houses, have been investigated as a mitigation strategy for these emissions. Although previous research demonstrated that VEBs can reduce NH3 and PM emissions, these studies used a limited number of samplers and did not examine concentration profiles. Moreover, the differences between daytime and nighttime emissions have not been investigated. In this study, we characterized emission profiles from a commercial poultry house using an array with multiple sampling heights and explored the differences between daytime and nighttime NH3 and PM profiles. We conducted three sampling campaigns, each with ten sampling events (five daytime and five nighttime), at a VEB-equipped poultry production facility. NH3 and PM samples were collected downwind from the ventilation tunnel fans before, within, and after the VEB. Results showed that ground-level concentrations beyond the VEB decreased to 8.0% ± 2.7% for NH3, 13% ± 4% for TSP, 13% ± 4% for PM10, and 2.4% ± 2.8% for PM2.5 of the original concentrations from the exhaust tunnel fan, with greater reduction efficiency during daytime than nighttime. Furthermore, pollutant concentrations were positively intercorrelated. These findings will be valuable for developing more effective pollutant remediation strategies in poultry house emissions.

Poultry farmers' knowledge, attitude, and practices toward poultry waste management in Bangladesh

Background and Aim

The improper handling of poultry litter and waste poses risks to humans and environment by introducing certain compounds, elements, and pathogenic microorganisms into the surrounding environment and food chain. However, understanding the farmers' knowledge, attitude, and practices (KAP) could provide insights into the constraints that hinder the appropriate adoption of waste management. Therefore, this study aimed to assess poultry farmers' KAP regarding waste management issues.

Materials and Methods

A cross-sectional KAP study was conducted with native poultry keepers and small-scale commercial poultry farmers in seven districts of Bangladesh. In the survey, 385 poultry producers were interviewed using validated structured questionnaires through face-to-face interviews to collect the quantitative data in their domiciles.

Results

The overall KAP of farmers regarding poultry waste management issues demonstrated a low level of KAP (p = 0.001). The analysis shows that roughly 5% of farmers have a high level of knowledge of poultry waste management issues, followed by around one-third of respondents having a moderate level of knowledge. Considering the attitude domain, more than one-fifth of native poultry keepers and nearly two-thirds of commercial producers demonstrated a low level of attitude toward poultry waste management. Considering the overall analysis, roughly half of the respondents found a high level of attitude, and over half of the farmers showed a moderate level of attitude toward poultry waste management issues. The analysis showed that the level of good practices for native and commercial poultry production systems is estimated at 77.3% versus 45.9%, respectively, despite the farmers' lesser knowledge and attitudes toward poultry waste management systems. Overall, analysis showed that nearly 60% and 40% of poultry producers had high and moderate levels, respectively, of good practices in poultry waste management issues.

Conclusion

Analysis of the KAP data shows that farmers had a low level of KAP toward poultry waste management. The result of this study will assist in formulating appropriate strategies and to adopt poultry waste management solutions by poultry farmers to reduce environmental degradation.

Mitigation Strategies of Air Pollutants for Mechanical Ventilated Livestock and Poultry Housing—A Review

The fast development of large-scale intensive animal husbandry has led to an increased proportion of atmospheric pollution arising from livestock and poultry housing. Atmospheric pollutants, including particulate matter (PM), ammonia (NH3), hydrogen sulfide (H2S), and greenhouse gases (GHG), as well as other hazardous materials (e.g., gases, bacteria, fungi and viruses), have significant influences upon the local atmospheric environment and the health of animals and nearby residents. Therefore, it is imperative to develop livestock and poultry housing mitigation strategies targeting atmospheric pollution, to reduce its negative effects on the ambient atmosphere and to promote sustainable agricultural production. In this paper, we summarize the various strategies applied for reducing outlet air pollutants and purifying inlet air from mechanical ventilated livestock and poultry housing. This review highlights the current state of knowledge on the removal of various atmospheric pollutants and their relative performance. The potential optimization of processes and operational design, material selection, and other technologies, such as electrostatic spinning, are discussed in detail. The study provides a timely critical analysis to fill the main research gaps or needs in this domain by using practical and stakeholder-oriented evaluation criteria.

Effect of air cleaner on stress hormones of pig and pork quality

The objective of this study is to investigate effect of air cleaner operated during pig breeding period on stress hormones of pigs and their pork quality. The stress hormones (cortisol, epinephrine and norepinephrine) in blood sample of pigs reared in the housing rooms with or without air cleaner have been measured according to a pig’s rearing stage: 0 day (farrowing), 21st day (farrowing–weaning), 70th day (weaning–nursery), 140th day (nursery–growing), and 180th day (growing–fattening). The comparison of pork quality according to the application of an air cleaner was performed through the carcass analysis of the pigs shipped from swine house. The levels of cortisol, epinephrine, and norepinephrine in pigs reared in housing rooms with and without air cleaners were found to be within the range of normal reference values. Among pork quality evaluation items, the thickness of intermuscular fat and final carcass grade of pigs raised in housing room with air cleaner was generally superior to those of pigs raised in housing room without air cleaner (p < 0.05). Based on the results obtained from this study, it is concluded that air cleaner does not have a significant effect on reducing pig stress but contributes to improving pork quality in pig breeding.

The Effect of Dietary Halloysite Supplementation on the Performance of Broiler Chickens and Broiler House Environmental Parameters

The aim of the study was to determine the effect of supplementing broiler chickens' diets with halloysite on daily body weight gain (BWG), feed conversion ratio (FCR), daily water consumption (DWC), and some broiler house hygiene parameters. The trial was conducted on 18,000 broiler chickens divided into two groups throughout the 42-day (D) rearing period. The birds were fed complete diets without (group C) or with halloysite addition (1%, group E) from D8 of rearing. No difference in the mortality rate was observed between groups C and E. Birds from group E had a tendency (0.05 < p < 0.10) towards a higher body weight at D32 and D42, a higher BWG, and a lower FCR compared to group C during the entire rearing period. Average DWC differed only in the finisher period, with a tendency towards lower overall DWC in group E. The concentration of ammonia in the air from D21 to D35 was increased more than 5-fold in group C but only 1.5-fold in group E. In conclusion, the use of halloysite as a feed additive in the diet of broiler chickens resulted in a reduction in feed consumption per unit of BWG and higher utilisation of crude protein, which led to improved environmental conditions.

Role played by the environment in the emergence and spread of antimicrobial resistance (AMR) through the food chain

The role of food-producing environments in the emergence and spread of antimicrobial resistance (AMR) in EU plant-based food production, terrestrial animals (poultry, cattle and pigs) and aquaculture was assessed. Among the various sources and transmission routes identified, fertilisers of faecal origin, irrigation and surface water for plant-based food and water for aquaculture were considered of major importance. For terrestrial animal production, potential sources consist of feed, humans, water, air/dust, soil, wildlife, rodents, arthropods and equipment. Among those, evidence was found for introduction with feed and humans, for the other sources, the importance could not be assessed. Several ARB of highest priority for public health, such as carbapenem or extended-spectrum cephalosporin and/or fluoroquinolone-resistant Enterobacterales (including Salmonella enterica), fluoroquinolone-resistant Campylobacter spp., methicillin-resistant Staphylococcus aureus and glycopeptide-resistant Enterococcus faecium and E. faecalis were identified. Among highest priority ARGs bla CTX -M, bla VIM, bla NDM, bla OXA -48-like, bla OXA -23, mcr, armA, vanA, cfr and optrA were reported. These highest priority bacteria and genes were identified in different sources, at primary and post-harvest level, particularly faeces/manure, soil and water. For all sectors, reducing the occurrence of faecal microbial contamination of fertilisers, water, feed and the production environment and minimising persistence/recycling of ARB within animal production facilities is a priority. Proper implementation of good hygiene practices, biosecurity and food safety management systems is very important. Potential AMR-specific interventions are in the early stages of development. Many data gaps relating to sources and relevance of transmission routes, diversity of ARB and ARGs, effectiveness of mitigation measures were identified. Representative epidemiological and attribution studies on AMR and its effective control in food production environments at EU level, linked to One Health and environmental initiatives, are urgently required.

Effects of montmorillonite on the growth performance, immunity, intestinal morphology and caecal microflora of broilers

Context Montmorillonite (MMT), as a potential antibiotic alternative, has rarely been reported in broiler chickens. Aims The present study was conducted to determine the effects of dietary MMT supplementation on the growth performance, immunity, intestinal microflora and morphological features of broilers. Methods One-day-old male broilers (Arbor Acres; n = 240) were randomly assigned to the following four groups before a 42-day feeding trial: (i) basal diet with no supplementation (control group); (ii) basal diet supplemented with 0.1% MMT; (iii) basal diet supplemented with 0.2% MMT; and (iv) basal diet supplemented with 0.3% MMT. Key results The results demonstrated that supplementation with 0.1% and 0.2% MMT markedly improved the average daily gain of broilers compared with the control group. Moreover, supplementation with 0.1% MMT remarkably decreased the total viable count of Escherichia coli in the caecum of broilers. Compared with the control group, 0.1% MMT supplementation significantly elevated the concentrations of secretory immunoglobulin A and systemic immunoglobulin G in the jejunal mucosa of broilers (P &lt; 0.05). Furthermore, MMT supplementation was associated with a greater villus height (VH) and a higher ratio of VH to crypt depth (CD) in the intestinal mucosa of broilers (P &lt; 0.05). However, in the duodenal and jejunal mucosa, dietary supplementation with MMT exhibited no significant (P &gt; 0.05) impact on the CD values of broilers compared with the control group. Conclusions This study showed that supplementation with 0.1% MMT could enhance broiler growth, increase the small intestinal VH and the VH:CD ratio, promote the intestinal-mucosa development, affect microflora population and improve immune function in the intestinal tract of broilers. Implications Supplementation with MMT could alter morphological changes in the intestinal villi, regulate microbial population and improve immune function in the intestinal tract, thus contributing to broiler growth. Our results indicated that MMT may serve as a natural beneficial feed additive for poultry gut health.

Degradation of ammonia from gas stream by advanced oxidation processes

The reduction of ammonia emissions from air was experimentally investigated by advanced oxidation processes (AOPs) utilizing the combination of ultraviolet irradiation with ozone. The influence of operating conditions such as initial ammonia concentration and flow rate of gas on the reduction of ammonia concentration was investigated in homemade photochemical unit. The conversion of ammonia decreased with increasing initial concentration of ammonia and with increasing flow rate of air (decreasing retention time). The highest conversion of ammonia (97%) was achieved under lower initial concentration of ammonia (30 ppm) and lower flow rate of air (28 m³/h). The energy per order was evaluated for the advanced oxidation process too. The energy consumption was about 0.037 kWh/m³/order for the 97% ammonia conversion at 30 ppm of initial ammonia concentration and 28 m³/h flow rate of air. Based on the results, the advanced oxidation process combining the UV irradiation and ozone was effective for mitigation of ammonia concentration and presents a promising technology for the reduction of odor emissions from livestock buildings. Moreover, the AOPs are suitable for application for high flow rate of air, especially for ammonia abatement from livestock buildings, where very high efficiency is expected.

The effect of feed supplementation with Zakarpacki zeolite (clinoptilolite) on percentages of T and B lymphocytes and cytokine concentrations in poultry

The available literature lacks information on the effect of Zakarpacki zeolite (clinoptilolite) on the immune system of poultry. Therefore, the aim of this study was to determine the effect of this zeolite on selected indicators of the immune response in poultry by evaluating the expression of cluster of differentiation (CD) surface molecules on T and B lymphocytes and the concentration of IL-2 and IL-10 in the blood. Ninety one-day-old Ross 308 broiler chicks were used in the study. The birds were divided into 3 groups of 30 each. The same basic diet was used in all groups, but groups II and III received a feed additive in the form of 2% and 3% zeolite. Blood samples were collected from all birds on the 40th day of observations. Weight gain in the birds in both experimental groups was significantly higher, and no clinical symptoms of disease were observed. The percentage of CD4+CD25+ T and B lymphocytes was higher in both groups receiving zeolite, but the percentage of CD8+CD25+ T lymphocytes was higher only in the group receiving 3% zeolite. There were no differences between the groups in the percentage of cells with CD3+ and MHC Class II expression. Higher serum concentrations of IL-2 and IL-10 were noted only in group III. The use of zeolites enhances antigen presentation and leads to increased Th1 and Th2 response. Excessive supply of zeolite in the feed leads to a local inflammatory response, which may cause damage to the intestinal barrier.

Odour emissions from poultry litter - A review litter properties, odour formation and odorant emissions from porous materials

Odour emissions from meat chicken sheds can at times cause odour impacts on surrounding communities. Litter is seen as the primary source of this odour. Formation and emission of odour from meat chicken litter during the grow-out period are influenced by various factors such as litter conditions, the environment, microbial activity, properties of the odorous gases and management practices. Odour emissions vary spatially and temporally. This variability has made it challenging to understand how specific litter conditions contribute to odour emissions from the litter and production sheds. Existing knowledge on odorants, odour formation mechanisms and emission processes that contribute to odour emissions from litter are reviewed. Litter moisture content and water thermodynamics (i.e. water activity, Aw) are also examined as factors that contribute to microbial odour formation, physical litter conditions and the exchange of individual odorant gases at the air-water interface. Substantial opportunities exist for future research on litter conditions and litter formation mechanisms and how these contribute to odour emissions. Closing this knowledge gap will improve management strategies that intercept and interfere with odour formation and emission processes leading to an overall reduction in the potential to cause community impacts.

Removal of odorous compounds from poultry manure by microorganisms on perlite--bentonite carrier

Laboratory-scale experiments were conducted using poultry manure (PM) from a laying hen farm. Six strains of bacteria and one strain of yeast, selected on the base of the previous study, were investigated to evaluate their activity in the removal of odorous compounds from poultry manure: pure cultures of Bacillus subtilis subsp. spizizenii LOCK 0272, Bacillus megaterium LOCK 0963, Pseudomonas sp. LOCK 0961, Psychrobacter faecalis LOCK 0965, Leuconostoc mesenteroides LOCK 0964, Streptomyces violaceoruber LOCK 0967, and Candida inconspicua LOCK 0272 were suspended in water solution and applied for PM deodorization. The most active strains in the removal of volatile odorous compounds (ammonia, hydrogen sulfide, dimethylamine, trimethylamine, isobutyric acid) belonged to B. subtilis subsp. spizizenii, L. mesenteroides, C. inconspicua, and P. faecalis. In the next series of experiments, a mixed culture of all tested strains was immobilized on a mineral carrier being a mixture of perlite and bentonite (20:80 by weight). That mixed culture applied for PM deodorization was particularly active against ammonia and hydrogen sulfide, which were removed from the exhaust gas by 20.8% and 17.5%, respectively. The experiments also showed that during deodorization the microorganisms could reduce the concentrations of proteins and amino acids in PM. In particular, the mixed culture was active against cysteine and methionine, which were removed from PM by around 45% within 24 h of deodorization.

Environmental impacts of French and Brazilian broiler chicken production scenarios: an LCA approach

This study compared the environmental burdens of two broiler chicken production systems in Brazil and two in France. One Brazilian system represents large-scale production in the Center-West region of the country; the other is a small-scale production in the South. One of the French systems represents an extensive broiler chicken production system, known as "Label Rouge"; the other is a standard system. Life-cycle impact assessments were performed using the CML-IA characterization method. The main functional unit adopted was 1 tonne of cooled and packaged chicken, ready for distribution. For the systems and impacts studied, production scale did not affect the environmental impact, but production intensity did. The extensive Label Rouge system had the largest impact among the impact categories studied. This resulted principally from the high feed-conversion ratio of this production system (3.1 kg of feed per kg of live weight) in conjunction with the fact that the feed-production stage contributed most to the overall impact. The contribution of deforestation to the crop-production stage was significant, particularly for climate change, equaling 19% of total emissions of CO2eq per tonne of cooled and packaged chicken, in the system of the Center-West of Brazil. The French systems were also affected, since they import crops from Brazil. The system of southern Brazil had less climate change impact because there is no longer deforestation in southern Brazil for crop production.

Effects of sodium bisulfate on the bacterial population structure of dairy cow waste

AIMS

To determine the effects of sodium bisulfate (SBS) on the bacterial populations in cattle waste.

METHODS AND RESULTS

We applied SBS at 0, 60, 70 or 100 kg week(-1) to cattle waste as it accumulated on the floors of four cattle pens, housing eight cattle each. We observed significant pH decreases in all of the treated wastes on day one; however, the 60 kg week(-1) treatment returned to control levels by day four, while the others remained significantly lower. Heterotrophic plate counts of the waste revealed that all treatments reduced the bacterial populations in the wastes on day one; however, all returned to control levels by day four. The 16S rRNA gene libraries derived from the wastes revealed significant reductions in sequences associated with the phyla Bacteroidetes and Firmicutes and increases in the Proteobacteria, Actinobacteria and Spirochaetes on day one, but resembled the control by day seven. Sequences associated with Escherichia coli increased significantly after SBS application, but became undetectable by day seven.

CONCLUSIONS

SBS application significantly alters the bacterial population structure of waste during the first few days of application, but the populations return to almost normal after 7 days.

SIGNIFICANCE AND IMPACT OF THE STUDY

Application of SBS to animal waste can reduce emissions; however, biosecurity precautions must be rigorously maintained during the initial application to ensure that pathogenic E. coli is not released into the environment.

Effects of sodium bisulfate on alcohol, amine, and ammonia emissions from dairy slurry

Sodium bisulfate (SBS) is extensively used in the poultry industry to reduce ammonia and bacterial levels in litter. It is also used in the dairy industry to reduce bacterial counts in bedding and ammonia emissions, preventing environmental mastitis and calf respiratory stress. The present study measured the effect of SBS on the air emission of ammonia, amine, and alcohol from a dairy slurry mix. Amine flux was undetectable (<5 ng L(-1)) across treatments. Application of SBS decreased ammonia, methanol, and ethanol emissions from fresh dairy slurry. Ammonia emissions decreased with increasing levels of SBS treatment. The 3-d average ammonia flux from the control (no SBS applied) and the three different SBS surface application levels of 0.125, 0.250, and 0.375 kg m(-2) were 513.4, 407.2, 294.8, and 204.5 mg h(-1) m(-2), respectively. The ammonia emission reduction potentials were 0, 21, 43, and 60%, respectively. Methanol and ethanol emissions decreased with an increase in the amount of SBS applied. The 3-d average methanol emissions were 223.7, 178.0, 131.6, and 87.0 mg h(-1) m(-2) for SBS surface application level of 0, 0.125, 0.250, and 0.375 kg m(-2), with corresponding reduction potentials of 0, 20, 41, and 61, respectively. Similar emission reduction potentials of 0, 18, 35, and 58% were obtained for ethanol. Sodium bisulfate was shown to be effective in the mitigation of ammonia and alcohol emissions from fresh dairy slurry.

Mitigation of ammonia and hydrogen sulfide emissions by stable aqueous foam-microbial media

Stable aqueous foam-microbial media consisting of protein-based foams and odor-degrading bacteria were developed to control the emissions of odorous compounds. The optimum foam formulation was determined based on foam characteristics including 50% drainage time, foam lifetime, and foam expansion ratio. When only the aqueous foam was applied onto the surface of a test odor source (i.e., swine manure), ammonia emission was completely suppressed for about 177, 225, 265, 297, and 471 min when the height of foam barrier was 2.5, 5, 10, 15, and 30 cm, respectively. According to the increasing foam height, ammonia emission rates after breakthrough points decreased to 0.16, 0.13, 0.09, 0.07, and 0.02 mg/m3/min, and thus volatilized ammonia concentrations decreased significantly after 600 min. Hydrogen sulfide was similarly suppressed. Ammonia emission was better controlled by incorporating odor-degrading bacteria into the aqueous foam. The odor suppression capacity of the 5-cm foam barrier with microbes was more than eight times greater than that of the barrier only and was similar to that of 30-cm foam barrier without microbes after 1440 min. A significant amount of dinitrogen gas was evolved by the foam-microbial media, indicating a successful biological transformation of ammonia.