Variability in human attractiveness to mosquitoes

Prescott SL, Dunstan JA, Hale J, Breckler L, et al. Clin Exp Allergy. 2005;35:1557–1564 PURPOSE OF THE STUDY. The authors recently demonstrated that young children with moderate-to-severe atopic dermatitis (AD) had significant clinical improvement in the severity and extent of their disease with the use of probiotics. The purpose of this study was to assess the effects of probiotics on underlying immune function and relate that to clinical improvement. STUDY POPULATION. Fifty-six Australian children aged 6 to 23 months with moderate-to-severe AD (based on a modified scoring AD [SCORAD] index of ≥25). METHODS. Subjects were randomly assigned to receive probiotics (1 × 109 colony-forming units of Lactobacillus fermentum; n = 26) or placebo (n = 27) twice daily for 8 weeks. Peripheral blood mononuclear cells were isolated from 53 children at baseline and at 8 and 16 weeks (8 weeks after the supplementation period). Cytokine (interleukin 5 [IL-5], IL-6, IL-10, IL-13, interferon γ [IFN-γ], and tumor necrosis factor α [TNF-α]) responses to allergens (egg ovalbumin, β-lactoglobulin, and house dust mite), vaccines (tetanus toxoid and diphtheria toxoid), intestinal flora (heat-killed L fermentum), skin flora (heat-killed Staphylococcus aureus), S aureus enterotoxin B (SEB), and mitogen (phytohemagglutinin) were assessed. RESULTS. The children who received probiotics showed a significant increase in T-helper 1 cytokine IFN-γ responses to SEB and phytohemagglutinin at 8 and 16 weeks compared with baseline. The increase in IFN-γ response to SEB was directly proportional to the decrease in the severity of AD during the study period. After supplementation with probiotics (week 8) children had significantly higher TNF-α responses to heat-killed L fermentum and heat-killed S aureus compared with those in the placebo group. This was not sustained at 16 weeks. IL-13 (a T-helper type 2 cytokine) responses to ovalbumin decreased significantly during the supplementation period, but this was not sustained after its discontinuation. No other effects of probiotics were seen on allergen-specific responses. CONCLUSIONS. Probiotics led to an increase in IFN-γ responses to nonspecific stimuli (SEB and phytohemagglutinin) and an increase in TNF-α responses to skin and intestinal flora. Clinical improvement in AD severity with probiotics was associated with significant increases in the T-helper 1 IFN-γ responses and altered responses to skin and intestinal flora but not consistent effects on allergen-specific responses. REVIEWER COMMENTS. It is interesting to note that this study did not show any consistent effects of probiotics on allergen-specific responses, which suggests more of an impact on innate immune pathways rather than allergen-specific ones. The results of this study show some promise for the use of probiotics in children with AD. However, there are many variables that need to be addressed, such as impact of underlying food allergy, exposure to antibiotics, and environmental factors. Larger studies are needed to further demonstrate clinical efficacy (short-term and long-term), to determine optimal timing and dosing of treatment, to further investigate immunologic mechanisms, and to determine the impact of probiotic treatment on later development of other atopic disorders (eg, asthma) in young children with AD.

Studies on the skin microbiota of amphibians in different disturbed habitats can clarify the relationship between the skin microbiota composition and environmental factors and have practical implications for the conservation of endangered species. In this study, 16S rRNA high-throughput sequencing was used to profile the skin microbiota of Maoershan hynobiids (Hynobius maoershanensis). Our results illustrate that the alpha diversity of the skin microbiota significantly differed among individuals in higher anthropogenic disturbance-degree (HADD) habitats and lower anthropogenic disturbance-degree (LADD) habitats. The diversity of the skin microbiota in forelimb bud-stage tadpoles from HADD habitats was higher than that in their counterparts from LADD habitats. The richness of the skin microbiota in hindlimb bud-stage tadpoles was greater in HADD habitats than in LADD habitats. However, the alpha diversity of the adult skin microbiota did not differ significantly between the two habitats. Furthermore, stepwise regression analysis indicated that the skin microbiota diversity and relative abundance of dominant bacteria decreased with increasing air temperature, water temperature, and pH; conversely, skin microbiota richness increased with increasing humidity. In addition, the relative abundance of dominant bacteria was influenced by anthropogenic disturbance. We conclude that the skin microbiota of Maoershan hynobiids is affected by ecological factors and anthropogenic disturbance, highlighting the importance of the skin microbiota in response to habitat alteration.

Identifying robust and reliable volatile organic compounds in human sebum for biomarker discovery

After the onset of the global COVID-19 pandemic, the deep connections between environmental factors and the transmission of airborne infectious diseases (including COVID-19) has become an area of relevant scientific and social interest. Indoor environments, where we spend a significant part of our daily lives, play a crucial role in shaping the dynamics of disease spread. The mitigation of infection risk related to poor indoor air quality and its link with the transmission of airborne diseases has emerged as a focal point for research and intervention strategies. This paper presents the results of a specific collaborative project in this field, focused on the utilization of Internet of Things (IoT) devices for comprehensive indoor environmental monitoring and infectious risk forecasting. In the frame of developing effective countermeasures for COVID-19 and future pandemic preparedness, our primary goal was to develop a predictive model for infection risk in indoor environments. Parameters such as humidity, temperature, CO2, and particulate matter concentrations (namely PM10 and PM2.5), have been assessed and modelled as indicators of indoor air quality, with these measures having been combined to generate a predictive algorithm specifically able to provide information about the transmission dynamics of COVID-19 and airborne infectious diseases within indoor spaces. This newly-developed Algorithm for the Prediction of Risk of Infections (APRI) relies on rigorous analyses and established different risk thresholds based on temperature, humidity, and CO2 levels. The model showed significant associations between environmental factors, such as temperature, CO2 levels, humidity, and particulate matter concentrations. A pivotal role of PM10 and PM2.5 in shaping air quality in indoor environments has been highlighted, as low PM concentrations corresponded in our predictive model to a minimal risk of airborne infectious diseases, while medium or high PM levels were associated with variations in temperature, humidity, and CO2 levels, thus corresponding to an elevated risk of infection, particularly in the frame of highly diffusive diseases like COVID-19.

Toluene downregulates filaggrin expression via the extracellular signal-regulated kinase and signal transducer and activator of transcription–dependent pathways

Immune dysregulation has been observed in individuals with sleep disturbance, with HLA molecules play a crucial role in the immune response. This study aimed to investigate the associations between HLA alleles and sleep behaviours, considering several environmental factors. Data were sourced from the UK Biobank. Logistic regression analyses were performed to explore the associations between 359 HLA alleles and 4 sleep behaviours, including chronotype (n = 204,636), insomnia (n = 227,553), snoring (n = 214,350) and daytime dozing (n = 227,197). Furthermore, gene-environmental interaction studies (GEIS) were conducted to evaluate the interactions of HLA alleles with environmental factors on sleep behaviours. This study analysed a total sample and subgroups stratified by sex to elucidate the impact of HLA alleles on sleep behaviours. Our findings revealed several associations between specific HLA alleles and sleep behaviours. Notably, HLA-A*23:01 was associated with evening chronotype in the total sample (OR = 0.918, 95%CI: 0.872-0.965), while HLA-A*32:01 was associated with evening chronotype in males (OR = 1.089, 95%CI: 1.037-1.144). Furthermore, GEIS identified multiple sets of interactions associated with sleep behaviours. For example, the interaction of HLA-DPA1*01:04 with alcohol consumption was associated with daytime dozing in the total sample (OR = 1.993, 95%CI: 1.351-2.941), while the interaction of HLA-DQB1*05:04 with ever suffered mental distress preventing usual activities was associated with insomnia in males (OR = 0.409, 95%CI: 0.254-0.658). Our findings highlight the involvement of HLA in sleep regulation and underscore the potential interactions between HLA alleles and environmental factors in modulating susceptibility to sleep behaviours.

Malaria is an infectious disease caused by the Plasmodium parasite which lives and reproduces in human red blood cells and is naturally transmitted through the bite of female Anopheles mosquitoes. Based on data from the Simalungun District Health Service, there were 955 cases of malaria in 2021 and the highest cases were in the Tanjung Tiram health center working area with 279 cases in 2021. Malaria transmission is influenced by several factors, including parasites, humans, mosquitoes and the environment. Environmental conditions have a big influence on the incidence of malaria, because a bad environment can increase the breeding and breeding of Anopheles mosquitoes. With spatial analysis, a mapping process can be carried out to determine the geographic distribution of potential disease risks and their relationship with existing environmental risk factors. Seeing the fluctuating incidence of malaria, it is necessary to carry out research to determine the distribution pattern and risk of malaria incidence in the working area of the Tanjung Tiram Community Health Center, Batubara Regency. The aim of this research is to determine environmental risk factors and malaria distribution patterns in the Tanjung Tiram health center working area, Batubara Regency. To find out the distribution of environmental risk factors in relation to malaria incidence so that it can provide input for the health service in the context of malaria control activities. Research sampling was carried out using a non-probability sampling method and the results of bivariate data analysis used Chi square. The results of this research are that there is a relationship between environmental risk factors such as ceilings, wall types, ventilation, wall density, screens on windows, the presence of puddles, gutters and swamps around the house with a p value of 0.000 and depicted in a distribution pattern map. which is able to optimize reducing the incidence of malaria cases.

Breast cancer is and remains among the most common types of cancer, estimated to be 16% of all new cancers diagnosed in 2025. While a variety of area-level social and environmental exposures have been implicated in breast cancer outcomes, comparatively less work has been done to study how multiple concurrent exposures to these factors impact outcomes. Importantly, a growing literature shows a high correlation of socioeconomic status (SES) and environmental exposures, highlighting the need for suitable exposure measurement methods which can account for this high correlation. Additionally, uncertainty in how many different SES and environmental factors may exist, an approach which does not require a priori specification of the number of clusters is also necessary. We identified Bayesian Profile Regression as a suitable clustering approach for our analysis which meets this set of needs. We utilized data from the United States Census American Community Survey 5-year estimates for 2020 and the United States Environmental Protection Agency Air Toxics Screening Assessment (AirToxScreen) estimates for 2020. Using area-level estimates of factors from all census tracts within Pennsylvania and New Jersey, we first identified clusters of SES risk factors—specifically, proportion of households that are single-headed, rented, crowded and without a vehicle, and proportion of people on public assistance, w/less than a high school diploma/equivalent (25 and older), unemployed (16 and older), and in poverty); identifying 21 unique neighborhood SES profiles, 11 of which had at least one component variable 1 standard deviation (SD) above the global mean. Using the same approach, we then identified clusters of environmental exposures, specifically, ambient exposure to: 8 volatile organic compounds, 4 heavy metals, and diesel particulate matter; identifying 29 unique neighborhood pollution profiles, 16 of which had at least one component variable that was 1 standard deviation above the global mean. When restricting to tracts within the Sidney Kimmel Comprehensive Cancer Center (SKCCC) catchment area, there was evidence of high global spatial autocorrelation for latent pollution clusters (Moran’s I of 0.82 (p<.001) and SES clusters (Moran’s I of 0.39, p<.001). Census tracts with poor SES profiles as well as tracts with greater than average pollution for one or more pollutants tended to cluster primarily in urban areas. By identifying area-level clusters of both environmental and SES risk factors for breast cancer, we can subsequently ask questions about how joint exposure to these factors may impact breast cancer incidence, mortality, survival, and stage at diagnosis. Importantly, by focusing on the smaller area level, these estimates and their impact on outcomes may also provide crucial evidentiary support for more targeted outreach efforts by the SKCCC Community Outreach and Engagement (COE) team and will inform research priorities for the region. Citation Format: Zachary H. Fusfeld, Terry Hyslop. Constructing latent clusters of joint exposure to census tract level socioeconomic and environmental breast cancer risk factors [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr A099.

Research into the effects of host genetics on HIV disease susceptibility and progression, and on the efficacy and toxicity of drug treatment, occupies a particular position in the landscape of HIV research...

Significant decreases in the volatile organic compound concentration, atmospheric oxidation capacity and photochemical reactivity during the National Day holiday over a suburban site in the North China Plain

Received: 2021-03-23 | Accepted: 2021-04-12 | Available online: 2021-12-31 https://doi.org/10.15414/afz.2021.24.04.297-300 The aim of this research was to find out the changes in fermentation parameters of whole-crop rye silage after adding the biological additive. Two variants of rye silage were used in the experiment: variant C (silage without additive) and variant A (silage with the addition of additive). The wilted whole-crop rye was treated with strains of lactic acid bacteria ( Pediococcus acidilactici , Lactobacillus paracasei and Lactococcus lactis 1.25x10 11 CFU.g -1 ) in a dose of 2 g of additive + 25 ml of water per 1 ton of matter. Both silage variants were ensiled with a vacuum pack device and after 2 months of storage, average samples were taken to determine the dry matter content, fermentation products, acidity of water extract, pH and the degree of proteolysis by appropriate methods. Treatment of rye silage with a microbial silage additive affected the quality of rye silage by a statistically significant (P <0.05) higher content of lactic acid and acidity of water extract. The lower content of acetic acid, alcohols, pH value and the degree of proteolysis were also statistically significant (P <0.05). The results confirmed the positive effect of the addition of Pediococcus acidilactici , Lactobacillus paracasei and Lactococcus lactis on the quality of the fermentation process of rye silage. Keywords: rye, silage, biological silage additives, fermentation quality References Adesogan, A. T. (2014, April). Avoiding the two greatest silage problems. In Proceedings of the 50th Florida dairy production conference (pp. 9–17). Alba-Mejía, J. E. A., Skládanka, J., Delgado, A. H., Klíma, M., Knot, P., Doležal, P. and Horký, P. (2016). The effect of biological and chemical additives on the chemical composition and fermentation process of Dactylis glomerata silage. Spanish journal of agricultural research, 14(2), 8. Arasu, M. V., Jung, M. W., Kim, D. H., Ilavenil, S., Jane, M., Park, H. S. and Choi, K. C. (2014). Enhancing nutritional quality of silage by fermentation with Lactobacillus plantarum. Indian journal of microbiology, 54(4), 396–402. Auerbach, H. and Theobald, P. (2020). Additive type affects fermentation, aerobic stability and mycotoxin formation during air exposure of early-cut rye (Secale cereale L.) silage. Agronomy, 10(9), 1432. Auerbach, H., Theobald, P., Kroschewski, B. and Weiss, K. (2020). Effects of various additives on fermentation, aerobic stability and volatile organic compounds in whole-crop rye silage. Agronomy, 10(12), 1873. Bíro, D., Juráček, M., Šimko, M., Gálik, B. and Rolinec, M. (2020). Preservation and preparation of feed. Nitra: Slovak University of Agriculture. In Slovak. Haag, N. L., Grumaz, C., Wiese, F., Kirstahler, P., Merkle, W., Nägele, H. J. and Oechsner, H. (2016). Advanced green biorefining: Effects of ensiling treatments on lactic acid production, microbial activity and supplementary methane formation of grass and rye. Biomass Conversion and Biorefinery, 6(2), 197–208. Herrmann, C., Heiermann, M. and Idler, C. (2011). Effects of ensiling, silage additives and storage period on methane formation of biogas crops. Bioresource technology, 102(8), 5153–5161. Huyen, N. T., Martinez, I. and Pellikaan, W. (2020). Using lactic acid bacteria as silage inoculants or direct-fed microbials to improve in vitro degradability and reduce methane emissions in dairy cows. Agronomy, 10(10), 1482. Choi, K. C., Ilavenil, S., Arasu, M. V., Park, H. S. and Kim, W. H. (2015). Effect of addition of lactic acid bacteria on fermentation quality of rye silage. Journal of the Korean Society of Grassland and Forage Science, 35(4), 277–282. Choi, K. C., Soundarrajan, I., Srisesharam, S., Park, H. S., Kim, J. H., Jung, J. S. and Kim, H. S. (2016). Potential effects of novel lactic acid bacteria on fermentation quality of rye haylage. Journal of the Korean Society of Grassland and Forage Science, 36(1), 23–28. Choi, K. C., Srigopalram, S., Ilavenil, S., Kuppusamy, P., Park, H. S., Yoon, Y. H. and Kim, H. S. (2017). Effect of addition of lactic acid bacteria on quality of rye silage harvested at early heading stage. Journal of The Korean Society of Grassland and Forage Science, 37(4), 332–336. Joo, Y. H., Lee, H. J., Lee, S. S., Han, O. K. and Kim, S. C. (2017). Effects of isolated bacteria application on chemical composition and fermentation characteristic of rye silage. Journal of Animal Science, 95, 141. Juráček, M., Bíro, D., Šimko, M., Gálik, B., Rolinec, M., Hanušovský, O., Struhár, P., Píšová, A. and Andruška, N. (2018). The influence of addition of Lactobacillus plantarum and Lactobacillus brevis on the fermentation quality of silages from permanent grassland. Journal of Central European Agriculture, 19(2), 385–393. Kim, D. H., Lee, S. S., Paradipta, D. H., Joo, Y. H., Lee, H. J., Kwak, Y. S. and Kim, S. C. (2017). Effect of homo or heterofermentative inoculants on fermentation characteristics and aerobic stability of rye silage. Journal of Agriculture and Life Science, 51(5), 81–89. Lee, S. S., Paradhipta, D. H., Joo, Y. H., Lee, H. J., Kwak, Y. S., Han, O. K. and Kim, S. C. (2018). Effects of selected inoculants on chemical compositions and fermentation indices of rye silage harvested at dough stage. Journal of the Korean Society of Grassland and Forage Science, 38(2), 99–105. Moore, E. B., Wiedenhoeft, M. H., Kaspar, T. C. and Cambardella, C. A. (2014). Rye cover crop effects on soil quality in no‐till corn silage–soybean cropping systems. Soil Science Society of America Journal, 78(3), 968–976. Morais, G., Daniel, J. L. P., Kleinshmitt, C., Carvalho, P. A., Fernandes, J. and Nussio, L. G. (2017). Additives for grain silages: A review. Slovak Journal of Animal Science, 50(1), 42–54. Oliveira, A. S., Weinberg, Z. G., Ogunade, I. M., Cervantes, A. A., Arriola, K. G., Jiang, Y. and Adesogan, A. T. (2017). Metaanalysis of effects of inoculation with homofermentative and facultative heterofermentative lactic acid bacteria on silage fermentation, aerobic stability, and the performance of dairy cows. Journal of Dairy Science, 100(6), 4587–4603. Paradhipta, D. H. V., Joo, Y. H., Lee, H. J., Lee, S. S., Kwak, Y. S., Han, O. K. and Kim, S. C. (2020). Effects of wild or mutated inoculants on rye silage and its rumen fermentation indices. Asian-Australasian journal of animal sciences, 33(6), 949.

Dirofilariasis is a vector-borne parasitic disease caused by Dirofilaria immitis and Dirofilaria repens.It predominantly affects dogs but can also be seen in cats and ferrets.The disease is transmitted through mosquito bites, with microfilariae developing into adult worms that reside in the pulmonary arteries and heart, causing severe cardiopulmonary complications.A suitable climate with ideal temperature and humidity is essential for sustaining mosquito populations and supporting the development of microfilariae into infective third-stage larvae within the vector.Diagnosis involves antigen testing, microfilariae detection, imaging techniques, and serological assays.Treatment includes adulticidal therapy, microfilaricidal drugs, and supportive care.Prevention is achieved through regular administration of macrocyclic lactones and mosquito control strategies.

Malaria is one of the most serious infectious diseases in the world. The African mosquito Anopheles gambiae sensu stricto (henceforth termed An. gambiae) is highly competent for malaria parasites and preferably feeds on humans inside houses, which make it one of the most effective vectors of the disease. Human body odours are presumably the most important cues that enable An. gambiae to find its host. Knowledge on the odours that mediate the host-seeking behaviour of malaria vectors is expected to contribute to novel intervention methods for disease control. The skin microbiota plays an important role in the production of human body odours and the human microbial and chemical signature displays a qualitative and quantitative correlation. Several studies have indicated a possible role of skin bacteria in the production of volatiles attractive to mosquitoes. The principle goal of this thesis was to understand the role of the human skin microbiota in mosquito-host interactions and to identify which compounds produced by these micro-organisms are involved in the attraction of An. gambiae to humans. Skin bacteria isolated from human feet and grown in vitro on agar plates attracted An. gambiae and this attraction was affected by incubation time and dilution of the skin microbiota. Semi-field experiments showed similar results and field experiments in Kenya suggested that skin bacterial volatiles also attract other disease vectors. Volatiles produced by five bacterial species common on the human skin showed that volatile blends produced by some species, including Staphylococcus epidermidis, were more attractive than blends produced by other species. Volatiles produced by Pseudomonas aeruginosa did not affect the behaviour of An. gambiae. Analysis of the volatiles produced by human skin microbiota grown in vitro led to the identification of 16 compounds, the majority of which had an effect on An. gambiae behaviour. 3-Methyl-1-butanol enhanced the attractiveness of a synthetic blend by a factor of three, and could be used to increase mosquito trap catches for monitoring or vector control purposes. 2-Phenylethanol decreased mosquito catches of a synthetic blend and may act as a spatial repellent. In order to examine the interaction between the microbiota on the skin and human attractiveness to mosquitoes, skin emanation and skin microbiota samples were taken from 48 individuals. The skin emanations from the individuals varied significantly in attractiveness to An. gambiae and several compounds originating from the skin were associated with individuals that were highly attractive or less attractive to mosquitoes. Individuals with a higher abundance of bacteria on their skin were more attractive to An. gambiae, whereas individuals with a higher diversity of skin microbiota were less attractive. Staphylococcus spp. were associated with individuals that were highly attractive and Pseudomonas spp. with individuals that were less attractive to mosquitoes. Human Leukocyte Antigens (HLA) genes are considered to influence the human body odour profile and HLA profile analysis of the 48 human individuals indicated that these genes may also affect the attractiveness of humans to mosquitoes. The studies described in this thesis show that volatiles produced by the human skin microbiota play an important role in the host-seeking behaviour of An. gambiae and the abundance and composition of the skin microbiota determine an individual’s attractiveness to mosquitoes. Optimised blends of the compounds identified can be used in push-pull strategies for the manipulation of mosquitoes, thereby reducing the number of malaria mosquitoes, the human-biting frequency, and the intensity of Plasmodium transmission. Research on the role of skin microbiota in the host-seeking behaviour and host preference of biting insects may lead to a better understanding of vector-host interactions and contribute to the fight against vector-borne diseases.

Abstract. There are thousands of volatile organic compound (VOC) species in ambient air, while existing techniques can only detect a small part of them (approximately several hundred). The large number of unmeasured VOCs prevents us from understanding the photochemistry of ozone and aerosols in the atmosphere. The major sources and photochemical effects of these unmeasured VOCs in urban areas remain unclear. The missing VOC reactivity, which is defined as the total OH reactivity of the unmeasured VOCs, is a good indicator for constraining the photochemical effect of unmeasured VOCs. Here, we identified the dominant role of anthropogenic emission sources in the missing VOC reactivity (accounting for up to 70 %) by measuring missing VOC reactivity and tracer-based source analysis in a typical megacity in China. Omitting the missing VOC reactivity from anthropogenic emissions in model simulations will remarkably affect the diagnosis of sensitivity regimes for ozone formation, overestimating the degree of VOC-limited regimes by up to 46 %. Therefore, a thorough quantification of missing VOC reactivity from various anthropogenic emission sources is urgently needed for constraints of air quality models and the development of effective ozone control strategies.

In the Northern Great Plains, interest in feeding cattle in enclosed beef deep-bedded mono-slope facilities (BDMF) has increased. Characterization of environmental factors impacting odor and gas emissions, nutrient excretion, and pathogens is needed to develop recommendations for management of BDMF. The objectives of this study were to determine spatial variability of ammonia (NH3) in the air and odorous volatile organic compounds (VOC) in the bedded pack and to quantify environmental factors during various seasons. The effects of environmental factors on concentrations of NH3 and VOC were determined. The nutrient content and occurrence of E. coli O157:H7 and generic E. coli concentrations in bedded pack material were also determined. High spatial variability was observed for steady-state NH3 concentration on the pen surface. Ammonia concentration increased as pack and ambient air temperatures increased (p < 0.01). The temperature humidity index inside the barn was significantly greater than outside the barn during hot and cold months. Concentrations of VOC were highest in transition areas between the bedded pack and the concrete floor. Depth, moisture content, and pH of the bedded pack were poorly correlated to concentrations of NH3 and VOC (r2 < 0.09). Manure from BDMF contained 80% volatile solids. E. coli O157:H7 prevalence and generic E. coli concentrations occurred at high levels in BDMF and varied seasonally. Priority should be given to NH3 and E. coli mitigation during hot months, but location-specific NH3 mitigation will not be effective due to random distribution in the pen. Frequent cleaning of areas surrounding the bedded pack should reduce VOC concentrations.