Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 119(27): e2123533119, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35759671

RESUMEN

High COVID-19 mortality among Black communities heightened the pandemic's devastation. In the state of Louisiana, the racial disparity associated with COVID-19 mortality was significant; Black Americans accounted for 50% of known COVID-19-related deaths while representing only 32% of the state's population. In this paper, we argue that structural racism resulted in a synergistic framework of cumulatively negative determinants of health that ultimately affected COVID-19 deaths in Louisiana Black communities. We identify the spatial distribution of social, environmental, and economic stressors across Louisiana parishes using hot spot analysis to develop aggregate stressors. Further, we examine the correlation between stressors, cumulative health risks, COVID-19 mortality, and the size of Black populations throughout Louisiana. We hypothesized that parishes with larger Black populations (percentages) would have larger stressor values and higher cumulative health risks as well as increased COVID-19 mortality rates. Our results suggest two categories of parishes. The first group has moderate levels of aggregate stress, high population densities, predominately Black populations, and high COVID-19 mortality. The second group of parishes has high aggregate stress, lower population densities, predominantly Black populations, and initially low COVID-19 mortality that increased over time. Our results suggest that structural racism and inequities led to severe disparities in initial COVID-19 effects among highly populated Black Louisiana communities and that as the virus moved into less densely populated Black communities, similar trends emerged.


Asunto(s)
Negro o Afroamericano , COVID-19 , Equidad en Salud , Disparidades en Atención de Salud , COVID-19/mortalidad , Disparidades en Atención de Salud/etnología , Humanos , Louisiana/epidemiología , Densidad de Población , Factores Raciales
2.
Environ Sci Technol ; 58(1): 280-290, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38153403

RESUMEN

While human mobility plays a crucial role in determining ambient air pollution exposures and health risks, research to date has assessed risks on the basis of almost solely residential location. Here, we leveraged a database of ∼128-144 million workers in the United States and published ambient PM2.5 data between 2011 and 2018 to explore how incorporating information on both workplace and residential location changes our understanding of disparities in air pollution exposure. In general, we observed higher workplace exposures relative to home exposures, as well as increased exposures for nonwhite and less educated workers relative to the national average. Workplace exposure disparities were higher among racial and ethnic groups and job types than by income, education, age, and sex. Not considering workplace exposures can lead to systematic underestimations in disparities in exposure among these subpopulations. We also quantified the error in assigning workers home instead of a weighted home-and-work exposure. We observed that biases in associations between PM2.5 and health impacts by using home instead of home-and-work exposure were the highest among urban, younger populations.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Estados Unidos , Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/análisis , Contaminación del Aire/análisis , Bases de Datos Factuales , Material Particulado/análisis
3.
Am J Ind Med ; 66(9): 713-727, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37329208

RESUMEN

BACKGROUND: Meatpacking plants were major sources of COVID-19 outbreaks, posing unprecedented risks to employees, family members, and local communities. The effect on food availability during outbreaks was immediate and staggering: within 2 months, the price of beef increased by almost 7% with documented evidence of significant meat shortages. Meatpacking plant designs, in general, optimize on production; this design approach constrains the ability to enhance worker respiratory protection without reducing output. METHODS: Using agent-based modeling, we simulate the spread of COVID-19 within a typical meatpacking plant design under varying levels of mitigation measures, including combinations of social distancing and masking interventions. RESULTS: Simulations show an average infection rate of close to 99% with no mitigation, 99% with the policies that US companies ultimately adopted, 81% infected with the combination of surgical masks and distancing policies, and 71% infected with N95 masks and distancing. Estimated infection rates were high, reflecting the duration and exertion of the processing activities and lack of fresh airflow in an enclosed space. CONCLUSION: Our results are consistent with anecdotal findings in a recent congressional report, and are much higher than US industry has reported. Our results suggest current processing plant designs made rapid transmission of the virus during the pandemic's early days almost inevitable, and implemented worker protections during COVID-19 did not significantly affect the spread of the virus. We argue current federal policies and regulations are insufficient to ensure the health and safety of workers, creating a justice issue, and jeopardizing food availability in a future pandemic.


Asunto(s)
COVID-19 , Animales , Bovinos , Humanos , Pandemias/prevención & control , Brotes de Enfermedades , Distanciamiento Físico , Arquitectura y Construcción de Instituciones de Salud
4.
Risk Anal ; 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37793779

RESUMEN

Climate change is expected to increase the frequency and intensity of natural hazards such as hurricanes. With a severe shortage of affordable housing in the United States, renters may be uniquely vulnerable to disaster-related housing disruptions due to increased hazard exposure, physical vulnerability of structures, and socioeconomic disadvantage. In this work, we construct a panel dataset consisting of housing, socioeconomic, and hurricane disaster data from counties in 19 states across the East and Gulf Coasts of the United States from 2009 to 2018 to investigate how the frequency and intensity of a hurricane correspond to changes in median rent and housing affordability (the interaction between rent prices and income) over time. Using a two-stage least square random-effects regression model, we find that more intense prior-year hurricanes correspond to increases in median rents via declines in housing availability. The relationship between hurricanes and rent affordability is more complex, though the occurrence of a hurricane in a given year or the previous year reduces affordable rental housing, especially for counties with higher percentages of renters and people of color. Our results highlight the multiple challenges that renters are likely to face following a hurricane, and we emphasize that disaster recovery in short- and medium-term should focus on providing safe, stable, and affordable rental housing assistance.

5.
Risk Anal ; 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36101014

RESUMEN

With the inexorable march of climate change, increased flooding is inevitable. Understanding the feedback between federal flood mitigation policies and the ways in which local governments build flood resilience is a significant gap in the literature. In particular, the effect that federal flood mitigation grants have on the intensity of local flood mitigation is nonexistent. This work measures flood risk mitigation by using the level of participation in FEMA's Community Rating System (CRS). Communities that participate in the CRS and undertake mitigation are awarded points; more points imply a higher level of participation. Since its inception in 1990, CRS communities have received considerably more federal pre-disaster flood mitigation grants compared to non-CRS communities. This study assesses the effect of federal pre-disaster flood mitigation grants on the level of participation in the CRS program. We use data on Hazard Mitigation Assistance programs and CRS participation data between 2010 and 2015. We link these data to flood risk and socioeconomic information. Our results indicate (i) federal pre-disaster flood mitigation grants do not appear to significantly influence the level of CRS participation, (ii) the effect of flood risk and socioeconomic factors on the level of CRS participation are mixed, and (iii) the current level of CRS participation is influenced by the previous level of CRS participation, which is not tied to federal pre-disaster flood mitigation grant. These findings add to the growing discussions on the drivers and barriers of local flood risk mitigation.

6.
Bioprocess Biosyst Eng ; 45(2): 333-344, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34862916

RESUMEN

Global demand for poultry and associated feed are projected to double over the next 30 years. Insect meal is a sustainable alternative to traditional feeds when produced on low-value high-volume agricultural byproducts. Black soldier fly (BSF) larvae (Hermetia illucens L.) are high in protein and contain methionine, an essential amino acid that is critical to poultry health. BSF larvae can be grown on many organic residues, however, larvae growth and quality vary based on feedstock and cultivation processes. Experiments were completed to monitor temporal changes in BSF larvae growth and composition using almond hulls as a growth substrate under batch and semi-batch processes and with varying substrate carbon to nitrogen ratio (C/N). A logistic kinetic growth model was developed to predict larval biomass and methionine accumulations during batch production. Estimated ranges of model parameters for larvae maximum specific growth rate and carrying capacity were 0.017-0.021 h-1 and 9.7-10.7 g larvae kg-1 hulls dry weight, respectively. Methionine content in larvae increased from 11.1 to 17.1 g kg-1 dry weight over a 30-day batch incubation period. Larvae-specific growth and yield increased by 168% and 268%, respectively, when cultivated in a semi-batch compared to a batch process. Increasing C/N ratio from 26 to 40 increased density of methionine content in larvae per unit feedstock by 25%. The findings demonstrate a logistic model can predict larvae biomass accumulation, harvest time can achieve specific methionine contents, and a semi-batch process is more favorable for larvae biomass accumulation compared to a batch process.


Asunto(s)
Alimentación Animal , Dípteros , Alimentación Animal/análisis , Animales , Biomasa , Dípteros/metabolismo , Larva , Metionina/metabolismo
7.
J Transp Geogr ; 89: 102894, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33519126

RESUMEN

In response to the COVID-19 pandemic, a growing number of states, counties and cities in the United States issued mandatory stay-at-home orders as part of their efforts to slow down the spread of the virus. We argue that the consequences of this one-size-fits-all order will be differentially distributed among economic groups. In this paper, we examine social distance behavior changes for lower income populations. We conduct a comparative analysis of responses between lower-income and upper-income groups and assess their relative exposure to COVID-19 risks. Using a difference-in-difference-in-differences analysis of 3140 counties, we find social distance policy effect on the lower-income group is smaller than that of the upper-income group, by as much as 46% to 54%. Our explorations of the mechanisms behind the disparate effects suggest that for the work-related trips the stay-at-home orders do not significantly reduce low income work trips and this result is statistically significant. That is, the share of essential business defined by stay-at-home orders is significantly negatively correlated with income at county level. In the non-work-related trips, we find that both the lower-income and upper-income groups reduced visits to retail, recreation, grocery, and pharmacy visits after the stay-at-home order, with the upper-income group reducing trips more compared to lower-income group.

8.
J Sci Food Agric ; 98(15): 5893-5900, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29999178

RESUMEN

BACKGROUND: The increasing production of almonds worldwide has resulted in the significant generation of byproduct streams that require end uses. One potential use for byproducts is for cultivation of additional food sources including insects. Studies were performed to determine if black soldier fly larvae (Hermetia illucens L.) could be cultivated on almond byproducts (hulls and shells) and to examine the effect of aeration and moisture on larvae growth and hull composition. RESULTS: Increasing aeration from 0.04 to 0.36 mL min-1 g dry weight-1 tripled the harvest weight of larvae and increased larvae yield by a factor of five. Larvae calcium content increased by 18% with an increase in aeration from 0.04 to 0.95 mL min-1 g dry weight-1 . Moisture content also affected harvest dry weight and yield; increasing moisture content from 480 g kg-1 (wet basis) to 680 g kg-1 increased harvest weight by 56% and yield by a factor of 2. Variables did not affect larvae methionine and cysteine content. Low moisture content and aeration rate yielded an environment that supported microbial consumption of hulls over larvae consumption and growth. CONCLUSIONS: The results demonstrate that almond hulls are a suitable feedstock for larvae production under controlled management of moisture content and aeration. © 2018 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Larva/crecimiento & desarrollo , Prunus dulcis/parasitología , Simuliidae/crecimiento & desarrollo , Residuos/análisis , Alimentación Animal/análisis , Animales , Larva/metabolismo , Nueces/química , Nueces/metabolismo , Nueces/parasitología , Prunus dulcis/química , Prunus dulcis/metabolismo , Simuliidae/metabolismo
9.
Nat Commun ; 15(1): 5106, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877029

RESUMEN

Publicly available electric vehicle (EV) infrastructure is pivotal for the United States EV transition by 2030. Existing infrastructure lacks equitably distribution to low-income and underrepresented communities, impeding mass adoption. Our study, utilizing 2021 micro-level data from 121 million United States households, comprehensively examines income and racial disparities in EV infrastructure accessibility. Our analysis of national averages indicates that lower-income groups face less accessibility to public EV infrastructure in both urban and rural geographies. Black households experience less rural accessibility, but greater urban accessibility compared to White households conditioning on income. However, our localized analysis uncovers significant variations in accessibility gaps among counties, rural and urban settings, and dwelling types. While Black households experience greater urban accessibility nationally, a closer look at the county level reveals diminishing advantages. This study identifies areas with pronounced inequality and urgent needs for enhanced accessibility, emphasizing the necessity for tailored solutions by local governments to enhance equitable access to EV infrastructure.

10.
Nat Commun ; 14(1): 7904, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036553

RESUMEN

Within coastal communities, sea level rise (SLR) will result in widespread intermittent flooding and long-term inundation. Inundation effects will be evident, but isolation that arises from the loss of accessibility to critical services due to inundation of transportation networks may be less obvious. We examine who is most at risk of isolation due to SLR, which can inform community adaptation plans and help ensure that existing social vulnerabilities are not exacerbated. Combining socio-demographic data with an isolation metric, we identify social and economic disparities in risk of isolation under different SLR scenarios (1-10 ft) for the coastal U.S. We show that Black and Hispanic populations face a disproportionate risk of isolation at intermediate levels of SLR (4 ft and greater). Further, census tracts with higher rates of renters and older adults consistently face higher risk of isolation. These insights point to significant inequity in the burdens associated with SLR.


Asunto(s)
Inundaciones , Elevación del Nivel del Mar , Estados Unidos , Transportes , Demografía
11.
Environ Sci Technol ; 51(3): 1053, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28067488
12.
Transl Anim Sci ; 6(3): txac071, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35854970

RESUMEN

Farmers in Nepal face many of the same global challenges associated with initiating and scaling poultry husbandry as many other developing countries. These include access to innovative approaches in finance, credit, coop design, marketing, and sales. As with most low-income countries, Nepalese poultry farmers also lack adequate training in poultry husbandry including biosecurity. In this paper, we describe a collaborative workshop-subsidy approach to addressing these challenges conducted by a partnership with the UC Davis School of Veterinary Medicine, the College of Engineering, the School of Education, and a farming co-operative based in the semi-rural area of Bhaktapur, Nepal. The program included two workshops covering aspects of poultry rearing including coop construction, chick rearing, biosecurity, and husbandry. Both workshops were a combination of lectures and hands-on learning. Following completion of the workshops, each farmer received subsidized materials for coop construction and poultry rearing. The co-operative provided training facilities and a market for selling eggs. Despite an outbreak of Highly Pathogenic Avian Influenza (HPAI), which affected the scale of program implementation, our results suggest that the workshop subsidy collaborative approach can be successful in reducing market entry barriers. Our 6-mo post-workshop survey showed that two-thirds of the workshop participants ultimately built their own coop and raised chicks. Half of these participants reported market available egg production and a doubling of egg consumption at home.

13.
Environ Sci Technol ; 45(13): 5846-52, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21609012

RESUMEN

Estimates of fuel use and air pollutant emissions from freight rail currently rely highly on aggregate methods and largely obsolete data which offer little insight into contemporary air quality problems. Because the freight industry is for the most part privately held and data are closely guarded for competitive reasons, the challenge is to produce robust estimates using current reporting requirements, while accurately portraying the spatial nature of freight rail impacts. This research presents a new spatially resolved model for estimating air pollutant emissions (hydrocarbons, carbon monoxide, nitrogen oxides, particulate matter less than 10 µm in diameter, sulfur dioxide, and carbon dioxide) from locomotives. Emission estimates are based on track segment level data including track grade, type of train traffic (bulk, intermodal, or manifest) and the local locomotive fleet (EPA tier certification level and fuel efficiency). We model the California Class I freight rail system and compare our results to regional estimates from the California Air Resources Board and to estimates following U.S. Environmental Protection Agency guidance. We find that our results vary considerably from the other methods depending on the region or corridor analyzed. We also find large differences in fuel and emission intensity for individual rail corridors.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Modelos Teóricos , Vías Férreas/instrumentación , Vías Férreas/estadística & datos numéricos , Emisiones de Vehículos/análisis , California , Dióxido de Carbono/análisis , Monóxido de Carbono/análisis , Hidrocarburos/análisis , Óxidos de Nitrógeno/análisis , Material Particulado/análisis , Dióxido de Azufre/análisis
14.
Artículo en Inglés | MEDLINE | ID: mdl-34831950

RESUMEN

In this paper we examine the effects of localized air pollution measurements on the housing prices in Oakland, CA. With high-resolution air pollution measurements for NO, NO2, and BC, we can assess the ambient air quality on a parcel-by-parcel basis within the study domain. We combine a spatial lag model with an instrumental variable method to consider both the spatial autocorrelation and endogeneity effects between housing prices and air pollution concentrations. To the best of our knowledge, this is the first work in this field that combines both spatial autocorrelation and endogeneity effects in one model with accurate air pollution concentration measurements for each individual parcel. We found a positive spatial autocorrelation with housing prices using Moral's I (value of 0.276) with the total sample number of 26,386. Somewhat surprisingly, we found a positive relationship between air pollution and housing prices. There are several possible explanations for this finding. Homeowners in high demand, low-stock housing areas, such as our study, may be insensitive to air pollution when the overall ambient air quality is relatively good. It is also possible that under clean air conditions, low variability in pollutant concentrations has little effect on property values. These hypotheses could be verified with more high-resolution air pollution measurements with a diversity of regions.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Vivienda , Material Particulado/análisis , Análisis Espacial , Factores de Tiempo
15.
Environ Sci Technol ; 44(23): 9134-42, 2010 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21058697

RESUMEN

Setting sustainability targets and evaluating systems progress are of great importance nowadays due to threats to the human society, to economic development and to ecosystems, posed by unsustainable human activities. This research establishes a probabilistic theoretical approach based on market expectations reflected in prices of publicly traded securities to estimate the time horizon until the appearance of new technologies related to replacement of nonrenewable resources, for example, crude oil and oil products. To assess time T when technological innovations are likely to appear, we apply advanced pricing equations, based on a stochastic discount factor to those traded securities whose future cash flows critically depend on appearance of such innovations. In a simple approximation of the proposed approach applied to replacement of crude oil and oil products, we obtain T ≈ (P(0)(oil)/C(0))·ln (Δ·P(0)(oil)/P(0)(alt)), where P(0)(oil) and P(0)(alt) are the current aggregate market capitalizations of oil and alternative-energy companies, C(0) is the annual aggregate dividends that oil companies pay to their shareholders at the present, and Δ is the fraction of the oil (oil products) replaced at time T. This formula gives T ≈ 131 years for replacement of gasoline and diesel. The proposed market-expectations approach may allow policymakers to effectively develop policies and plan for long-term changes.


Asunto(s)
Conservación de los Recursos Naturales/tendencias , Predicción/métodos , Comercio , Conservación de los Recursos Naturales/economía , Fuentes Generadoras de Energía/economía , Fuentes Generadoras de Energía/estadística & datos numéricos , Industria Procesadora y de Extracción/economía , Industria Procesadora y de Extracción/estadística & datos numéricos , Modelos Teóricos , Petróleo/economía , Petróleo/estadística & datos numéricos , Tecnología/tendencias
16.
Poult Sci ; 98(2): 785-788, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30289525

RESUMEN

As commercial free-range and pastured poultry production has gained increased popularity in the United States in recent years, there is a greater need to understand basic husbandry practices including feeding and lighting practices. Because husbandry practices vary greatly between individual commercial pastured poultry and free-range operations, gaining knowledge across a wide cross-section of producers is necessary to better understand current practices. Specifically, because feed is considered the most expensive part of poultry production with respect to operating cost, in collaboration with the American Pastured Poultry Producers Association, an on-line survey of commercial free-range and pastured poultry producers was conducted aimed primarily at evaluating feeding and lighting practices. Data were collected from 14 commercial pastured (n = 13) and free-range (n = 1) producers (6 broiler, 1 layer, and 7 broiler/layer facilities) across 9 U.S. states. Results showed that these operations most commonly use Cornish Cross for broiler production and ISA Brown and Australorp for egg production. Only 1 of the 14 farms calculates feed conversion ratio on a monthly basis. Estimates of Hen Month Egg Production (HMEP) resulted in HMEP percentages that were over 100% in 6 of the 7 farms that provided data. 5 of the 7 farms that have layers used supplemental lighting but do not use a lux meter. These lack of data reflect an important challenge with this segment of the poultry industry. Extension based outreach focused on enabling data collection and record-keeping and analysis are necessary. Despite its small sample size, this study's results provide some valuable insights with respect to feeding equipment and the current state of data collection for this segment of the poultry industry.


Asunto(s)
Alimentación Animal/estadística & datos numéricos , Crianza de Animales Domésticos/métodos , Pollos/fisiología , Iluminación/estadística & datos numéricos , Animales , Pollos/clasificación , Femenino , Masculino , Encuestas y Cuestionarios , Estados Unidos
17.
NPJ Sci Food ; 3: 15, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31508493

RESUMEN

Increases in global human population are leading to increasing demands for food production and waste management. Insect biomass is a sustainable alternative to traditional animal feeds when insects are produced on lignocellulosic by-products. Resources high in lignocellulose have high carbon to nitrogen ratios and require nitrogen supplementation to accelerate bioconversion. Here we report on studies that examine the influence of nitrogen supplementation of almond hull-based feedstocks on black soldier fly larvae (Hermetia illucens L.) cultivation and composition. Decreasing carbon to nitrogen ratio from 49 to 16 increased larvae harvest dry weight, specific larvae growth, and yield by 36%, 31%, and 51%, respectively. However, the decrease in carbon to nitrogen ratio decreased larvae methionine and cysteine contents by 11% and 13%, respectively. The findings demonstrate that carbon to nitrogen ratio can be managed to enhance bioconversion of lignocellulose to larvae, but that this management approach can reduce larvae amino acid content.

18.
Artículo en Inglés | MEDLINE | ID: mdl-30577442

RESUMEN

Exposure to high air pollutant concentrations results in significant health risks. Many communities of color and low-income communities face disproportionately higher levels of air pollution exposure. Environmental justice (EJ) screening tools play a critical role in focusing early attention on areas with a high likelihood of disparate health impacts. In 2015, the United States Environmental Protection Agency (US EPA) released EJScreen, a screening tool with indicators of a range of pollution burdens across the US. However, little is known about the accuracy of the screening estimates of pollution exposure. This study compares EJScreen's traffic proximity air quality metric to dispersion modeling results. Using the area around the Houston Ship Channel, we conduct fine-grained air pollution dispersion modeling to evaluate how closely EJScreen's indicator approximates estimated roadway air pollution concentrations. We find low correlation between modeled concentrations and the EJScreen roadway air pollution indicator. We extend EJScreen's roadway air pollution screening method in three ways: (1) using a smaller unit of analysis, (2) accounting for the length of each road segment, and (3) accounting for wind direction. Using the Houston region, we use two of the methods and show that the proposed extensions provide a more accurate transportation air pollution screening assessment at the regional and local level.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , United States Environmental Protection Agency , Emisiones de Vehículos/análisis , Exposición a Riesgos Ambientales/análisis , Humanos , Material Particulado/análisis , Estados Unidos
20.
Poult Sci ; 96(4): 957-965, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-27744297

RESUMEN

While pasture-raised poultry comprises a small portion of the commercial poultry industry in North America, these alternative rearing systems have become increasingly popular. As such, it is critical to improve our understanding of husbandry practices and prevalence of zoonotic and epizoonotic diseases in these systems. This research reviews the results of a survey sent to 82 commercial pastured poultry farms in California. While the survey response was low (13.4%), it was enhanced by detailed in-person interviews and farm visits. In addition, we conducted drag swabs for Salmonella Enteritidis. On average, farms utilized 12.3% of their total farmland for pastured poultry operations, which often coexisted with other livestock (45%), touch crops (27%), and non-touch crops (45%). While the mean (44.6 sq. ft./hen) and median (22.2 sq. ft./hen) pasture stocking densities were within auditing guidelines, the mean (1.2 sq. ft./hen) and median (0.5 sq. ft./hen) coop stocking densities were below the pending USDA (2016) guidelines recommended in 7 CFR Part 205. Drag swab results showed the presence of Salmonella Enteritidis (SE) in the environment of one of the 11 farms (9.1%). In addition, Salmonella Pullorum (SP) whole blood agglutination tests were used to understand the prevalence of Salmonella spp. in laying hens within the studied farms. Results showed the presence of antibodies in flocks at six of the seven non-SE vaccinated farms, with a mean on-farm prevalence of 25.6% in laying hens. Logistic regression was used to determine risk factors for Group D Salmonella exposure in non-vaccinated flocks, using the SP blood agglutination data as the dependent variable and the survey questions as the independent variables. Statistically significant (P < 0.05) risk factors included exposed wire floors and flock size. These results improve our understanding of Salmonella prevalence and husbandry practices on commercial pastured poultry farms in California.


Asunto(s)
Pollos , Enfermedades de las Aves de Corral/epidemiología , Salmonelosis Animal/epidemiología , Salmonella enterica/fisiología , Salmonella enteritidis/fisiología , Crianza de Animales Domésticos , Animales , California/epidemiología , Femenino , Modelos Logísticos , Vigilancia de la Población , Enfermedades de las Aves de Corral/microbiología , Factores de Riesgo , Salmonelosis Animal/microbiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA