Air contaminants in different European farming environments.
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Farmers are known to be at high risk from the development of occupational airway disease. The first stage of the European farmers' study has shown that pig farmers in Denmark and Germany, poultry farmers in Switzerland and greenhouse workers in Spain were at highest risk for work-related respiratory symptoms. Therefore, the aim of this study was to determine exposure levels at relevant farm workplaces. Dust and endotoxin levels as well as microbiological concentrations were determined in 213 crop and animal farming environments by personal sampling. The highest total dust concentrations were found in poultry houses in Switzerland with median concentrations of 7.01 mg/m(3). The median airborne endotoxin concentrations in total dust ranged between 0.36 ng/m(3) in Spanish greenhouses and 257.58 ng/m(3) in poultry houses in Switzerland. Likewise, the highest median concentrations of total (2.0 x (7) cells/m(3)) and active fungi (4.4 x (5) cfu/m(3)) have been found in Swiss poultry houses. The predominant fungus taxa discovered in poultry houses were Eurotium spp. and thermophilic fungi. Cladosporium and Botrytis were mainly detected in greenhouses. The exposure level found in this study might put the farmers at risk from respiratory diseases. (+info)
Nutrition affects fat-free body composition in broiler chickens.
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The independence of fat-free body composition from nutrition is assumed in most models that simulate animal growth. This assumption has not been investigated extensively. We studied the allometric relationships between water and ash with protein in growing broiler chickens and tested whether the amounts of water or ash at a given protein weight was affected by nutritional factors. Two experiments, each with a 2 x 9 factorial design, were conducted using male broiler chickens of two body weight ranges [200-800 g (expt. 1) and 800-1600 g (expt. 2)]. The treatment factors were two levels of feed intake and nine dietary ideal protein to protein-free energy ratios (PE-ratio). Protein was balanced for amino acid content. The allometric relationships of water and ash with protein were different for carcass and organs. The relationship between water and protein was not affected by nutrition, except for a 7% reduction in water weight at a fixed protein weight in the carcass in expt. 1 at the lowest compared with the highest PE-ratio (P < 0.001). The relationship between ash and protein was strongly affected by nutrition. The lowest PE-ratio increased ash weight at a fixed protein weight in the carcass by up to 28%, compared with the highest PE-ratio (P < 0.001). We conclude that, at least for modern meat-type animals, nutrition can significantly affect fat-free body composition at a certain fat-free body weight. The nutritional effects on fat-free body composition could be incorporated into models of the chemical body composition of growing animals. (+info)
Different levels of genetic homogeneity in vancomycin-resistant and -susceptible Enterococcus faecium isolates from different human and animal sources analyzed by amplified-fragment length polymorphism.
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The genetic relationship among fecal vancomycin-resistant Enterococcus faecium (VREF) and vancomycin-susceptible E. faecium (VSEF) isolates (n = 178) from the same populations of pigs, human healthy volunteers, and hospitalized patients (from The Netherlands) and chickens (from The Netherlands and Greece) was studied by amplified-fragment length polymorphism (AFLP). The majority of VREF isolates from pigs, healthy volunteers, and hospitalized patients grouped together (genetic similarity, >or=65%). In a previous AFLP study by our group the VREF isolates from hospitalized patients grouped separately, most likely because these were clinical and not fecal isolates as in the present study. Furthermore, VSEF isolates from humans and pigs were found much more genetically diverse than VREF isolates, whereas VREF and VSEF isolates from chickens clustered together in a separate genogroup (genetic similarity, >or=65%), a pattern clearly distinct from the patterns for human and pig isolates. The present study suggests that pigs are a more important source of VREF for humans than chickens and that human- and pig-derived VSEF isolates seem much more heterogeneous than VREF isolates. (+info)
Molecular characterization of multiresistant d-tartrate-positive Salmonella enterica serovar paratyphi B isolates.
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Since 1996, the National Salmonella Reference Laboratory of Germany has received an increasing number of Salmonella enterica subsp. enterica serovar Paratyphi B isolates. Nearly all of these belonged to the dextrorotatory tartrate-positive variant (S. enterica subsp. enterica serovar Paratyphi B dT(+)), formerly called S. enterica subsp. enterica serovar Java. A total of 55 selected contemporary and older S. enterica subsp. enterica serovar Paratyphi B dT(+) isolates were analyzed by plasmid profiling, antimicrobial resistance testing, pulsed-field gel electrophoresis, IS200 profiling, and PCR-based detection of integrons. The results showed a high genetic heterogeneity among 10 old strains obtained from 1960 to 1993. In the following years, however, new distinct multiresistant S. enterica subsp. enterica serovar Paratyphi B dT(+) clones emerged, and one clonal lineage successfully displaced the older ones. Since 1994, 88% of the isolates investigated were multiple drug resistant. Today, a particular clone predominates in some German poultry production lines, poultry products, and various other sources. It was also detected in contemporary isolates from two neighboring countries as well. (+info)
Development of a real-time reverse transcriptase PCR assay for type A influenza virus and the avian H5 and H7 hemagglutinin subtypes.
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A real-time reverse transcriptase PCR (RRT-PCR) assay based on the avian influenza virus matrix gene was developed for the rapid detection of type A influenza virus. Additionally, H5 and H7 hemagglutinin subtype-specific probe sets were developed based on North American avian influenza virus sequences. The RRT-PCR assay utilizes a one-step RT-PCR protocol and fluorogenic hydrolysis type probes. The matrix gene RRT-PCR assay has a detection limit of 10 fg or approximately 1,000 copies of target RNA and can detect 0.1 50% egg infective dose of virus. The H5- and H7-specific probe sets each have a detection limit of 100 fg of target RNA or approximately 10(3) to 10(4) gene copies. The sensitivity and specificity of the real-time PCR assay were directly compared with those of the current standard for detection of influenza virus: virus isolation (VI) in embryonated chicken eggs and hemagglutinin subtyping by hemagglutination inhibition (HI) assay. The comparison was performed with 1,550 tracheal and cloacal swabs from various avian species and environmental swabs obtained from live-bird markets in New York and New Jersey. Influenza virus-specific RRT-PCR results correlated with VI results for 89% of the samples. The remaining samples were positive with only one detection method. Overall the sensitivity and specificity of the H7- and H5-specific RRT-PCR were similar to those of VI and HI. (+info)
Reflection on the history, coordination, and funding trends for U.S. public meat research: information to enhance resource allocation.
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A study was conducted to analyze resource allocation for public meat research in the United States and characterize the portfolio of meat research investments. Trends in the amount of public resources provided for meat research (beef, pork, lamb, and poultry) were analyzed for fiscal years 1980, 1985, 1990, 1995, and 1997. An in-depth analysis was conducted for data from fiscal year 1998 to characterize the profile of the research portfolio. Funding levels and scientist-year equivalents were aggregated to represent the measures of resource allocation for three mutually exclusive research categories: 1) meat quality, 2) food safety, and 3) product development and processing. Data for the 1998 profile analysis were derived from a computer search based on the combination of key words and research classification codes to avoid duplication and cluster research projects. Individual research projects were individually reviewed and a percentage was assigned to four mutually exclusive research categories: 1) meat quality, 2) food safety, 3) product development and processing, and 4) marketing. As meat research evolved over the past century, considerable efforts were expended by researchers and administrators to ensure the coordination of research and program relevance. This is demonstrated by the establishment of numerous multistate research committees. Total funding for meat science increased only modestly when adjusted for inflation during the two decades of this study; however, notable changes occurred in the distribution of resources in the portfolio. Funding for meat quality and product development and processing remained virtually unchanged when adjusted for inflation, whereas funding for food safety increased considerably. The total number of scientists conducting meat research remained virtually unchanged during the period, but the proportion allocated to food safety research increased substantially. The federal portion of total funding decreased from 61.3% to 51.6% between 1980 and 1997, whereas the percentage from both state appropriations and private sources increased. Modifications in research emphasis were influenced by industry problems such as meat quality, public perceptions about food safety, the availability of research funding, scientific advances occurring in molecular biology and genetic manipulation, and the changing meat industry. The information in this paper provides administrators and researchers the opportunity to make better informed decisions about resource allocation for meat research. (+info)
Drug resistances in salmonella isolates from animal foods, italy 1998-2000.
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We investigated the distribution of serotypes and patterns of drug resistance of 206 strains of salmonella isolated in southern Italy in the years 1998-2000 from raw food of animal origin, faeces of food animals and animal feed. To improve knowledge of mobile genetic elements carrying the resistance genes, some molecular features were also investigated within isolates resistant to three or more antibiotics. A high proportion of isolates, 52.2% and 37.7%, respectively, belonging to both Typhimurium and other serotypes of animal origin, proved to be multidrug resistant. The DT104 complex specific multidrug pattern of resistance was quite infrequent among isolates other than Typhimurium, but resistances to nalidixic acid and kanamycin were more frequent within these last ones (36.9% vs. 11.4% and 56.5% vs. 2.2%, respectively). Class I integrons were detected in isolates of Typhimurium and seven different serotypes. The relevance of food animal environment as a drug resistance reservoir and animal food as a potential resistance gene vehicle between the farm and human ecological niches is confirmed by our findings. (+info)
Human salmonellosis associated with young poultry from a contaminated hatchery in Michigan and the resulting public health interventions, 1999 and 2000.
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Although approximately 95% of disease caused by nontyphoidal salmonella is transmitted by foodborne vehicles, four documented salmonella outbreaks in the 1990s have been traced to contact with young poultry. No environmental studies of source hatcheries were completed. This case-control study was performed by comparing culture-confirmed Salmonella Infantis in Michigan residents, identified between May and July 1999, with two age- and neighbourhood-matched controls. Eighty environmental and bird tissue samples were collected from an implicated hatchery; all salmonella isolates underwent pulsed-field gel electrophoresis (PFGE) analysis. The study included 19 case-patients sharing the same PFGE subtype and 37 matched controls. Within 5 days before illness onset, 74% of case-patients resided in households raising young poultry compared with 16% of controls (matched OR 19.5; 95% CI 2.9, 378.1). Eight hatchery samples yielded Salmonella Infantis with PFGE subtypes matching the patients' isolates. This investigation identified birds from a single hatchery as the source of human illness and confirmed the link by matching PFGE patterns from humans, birds and the hatchery environment. Subsequent public health interventions reduced, but did not eliminate, transmission of poultry-associated salmonellosis. Five additional PFGE-linked cases were identified in Spring 2000, necessitating quarantine of the hatchery for depopulation, cleaning and disinfection. (+info)