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Hansen M.J.,University of Aarhus | Adamsen A.P.S.,University of Aarhus | Feilberg A.,University of Aarhus | Jonassen K.E.N.,Pig Research Center
Journal of Environmental Quality | Year: 2011

Odor from pig production facilities is typically measured with olfactometry, whereby odor samples are collected in sampling bags and assessed by human panelists within 30 h. In the present study, the storage stability of odorants in two types of sampling bags that are often used for olfactometry was investigated. The bags were made of Tedlar or Nalophan. In a field experiment, humid and dried air samples were collected from a pig production facility with growing-finishing pigs and analyzed with a gas chromatograph with an amperometric sulfur detector at 4, 8, 12, 28, 52, and 76 h after sampling. In a laboratory experiment, the bags were filled with a humid gas mixture containing carboxylic acids, phenols, indoles, and sulfur compounds and analyzed with proton-transfer-reaction mass spectrometry after 0, 4, 8, 12, and 24 h. The results demonstrated that the concentrations of carboxylic acids, phenols, and indoles decreased by 50 to >99% during the 24 h of storage in Tedlar and Nalophan bags. The concentration of hydrogen sulfide decreased by approximately 30% during the 24 h of storage in Nalophan bags, whereas in Tedlar bags the concentration of sulfur compounds decreased by <5%. In conclusion, the concentrations of odorants in air samples from pig production facilities significantly decrease during storage in Tedlar and Nalophan bags, and the composition changes toward a higher relative presence of sulfur compounds. Th is can result in underestimation of odor emissions from pig production facilities and of the eff ect of odor reduction technologies. © 2011 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. Source


Osteochondrosis (OC) is a degenerative condition of the cartilage seen in growing animals. The objective of the study was to investigate (1) the prevalence of macroscopically visible OC in the elbow of finishing pigs, (2) the relationship between changes in the surface of the articular cartilage and changes in the underlying cartilage and bone and the synovial membrane, and (3) the association between growth rate and the occurrence of OC in the elbow. The study used 9696 finishing pigs from three herds. After slaughter, the left elbow joint of each pig was examined, and macroscopically visible lesions in the articular cartilage, subchondral bone and synovial membrane were recorded. The highest prevalences of OC lesions were found in the humeral condyle with thickening of the articular cartilage (53%), irregularity of the articular cartilage (32%), lesions in the subchondral bone (26%), fissures under the cartilage (21%) and osteochondrosis dissecans (OCD) (14%). Irregularity of the articular cartilage was strongly associated with fissures under the cartilage and lesions in the subchondral bone (OR 13.7 and 5.8, respectively). Irregularity of the articular cartilage and OCD were associated with villous proliferation of the synovial membrane. For each additional 100 g of average daily gain in the weaner period or in the finishing period, the risk of irregularity in the articular cartilage and OCD increased by approximately 20% (ORs ranging between 1.14 and 1.20 for both weaners and finishers). © 2010 Elsevier Ltd. Source


Hansen K.H.,Copenhagen University | Damborg P.,Copenhagen University | Andreasen M.,Pig Research Center | Nielsen S.S.,Copenhagen University | Guardabassi L.,Copenhagen University
Applied and Environmental Microbiology | Year: 2013

Current knowledge on extended-spectrum beta-lactamases (ESBLs) in animals is based largely on cross-sectional studies and qualitative data. The aim of this longitudinal study was to elucidate carriage proportions and fecal counts of ESBL-producing Escherichia coli in pigs during the production cycle. At each of three ESBL-positive single-sited farrow-to-finisher pig farms (farms A, B, and C) included in the study, individual fecal samples were taken from 17 to 20 sows 1 week before farrowing and from 2 piglets of each sow's litter four times from birth to slaughter (as piglets, weaners, and finishers). Cefotaxime (CTX)-resistant coliforms in feces were counted on MacConkey agar containing 2 μg/ml CTX and characterized for the presence of ESBLencoding genes by PCR and sequencing. CTX-M-positive pigs were detected in all age groups at farms A (blaCTX-M-9 group, compatible with blaCTX-M-14/17) and B (blaCTX-M-1 group, compatible with blaCTX-M-1/61), whereas only three weaners were positive at farm C (blaCTX-M-1 group, compatible with blaCTX-M-1/61). A significant decrease in carriage was detected during the production cycle, with on average 50% carriage immediately after birth, 58% just before weaning, 29% during weaning, and 12% during finishing. The observed reduction in numbers of CTX-M-positive pigs was accompanied by a significant reduction in mean fecal counts of CTX-resistant coliforms from~107 CFU/g in piglets to~103 CFU/g in finishers (P<0.001). These findings provide novel information about the epidemiology of ESBLs at the farm level and have important implications for assessments of risks of meat contamination during slaughter.© 2013, American Society for Microbiology. Source


Liu D.,University of Aarhus | Feilberg A.,University of Aarhus | Adamsen A.P.S.,University of Aarhus | Jonassen K.E.N.,Pig Research Center
Atmospheric Environment | Year: 2011

The emission of odorous compounds from intensive pig production facilities is a nuisance for neighbors. Slurry ozonation for odor abatement has previously been demonstrated in laboratory scale. In this study, the effect of slurry ozonation (combined with solid-liquid pre-separation and acidification) on emissions of odorous compounds was tested in an experimental full-scale growing pig facility using Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) for online analysis of odorants. The measurements were performed to gain a better understanding of the effects of ozone treatment on emissions odorous compounds and to identify potential options for optimization of ozone treatment. The compounds monitored included volatile sulfur compounds, amine, carboxylic acids, ketones, phenols and indoles. Measurements were performed during nearly a one-month period in summertime. The compounds with the highest concentrations observed in the ventilation exhaust duct were acetic acid, hydrogen sulfide, propanoic acid and butanoic acid. The compounds with the highest removal efficiencies were hydrogen sulfide, 3-methyl-indole, phenol and acetic acid. Based on odor threshold values, methanethiol, butanoic acid, 4-methylphenol, hydrogen sulfide and C 5 carboxylic acids are estimated to contribute significantly to the odor nuisance. Emissions of odorous compounds were observed to be strongly correlated with temperature with the exception of hydrogen sulfide. Emission peaks of sulfur compounds were seen during slurry handling activities. Discharging of the slurry pit led to reduced hydrogen sulfide emissions, but emissions of most other odorants were not affected. The results indicate that emissions of odorants other than hydrogen sulfide mainly originate from sources other than the treated slurry, which limits the potential for further optimization. The PTR-MS measurements are demonstrated to provide a quantitative, accurate and detailed evaluation of ozone treatment for emission reduction. © 2011 Elsevier Ltd. Source


Feilberg A.,University of Aarhus | Liu D.,University of Aarhus | Adamsen A.P.S.,University of Aarhus | Hansen M.J.,University of Aarhus | Jonassen K.E.N.,Pig Research Center
Environmental Science and Technology | Year: 2010

Emission of odorous compounds from intensive livestock production is a cause of nuisance in populated rural areas. Knowledge on the chemical composition of odor and temporal variations in emissions are needed in order to identify factors of importance for emission rates and select proper abatement technologies. In this work, a method based on proton-transfer-reaction mass spectrometry (PTR-MS) has been developed and tested for continuous measurements of odorant emissions from intensive pig production facilities. The method is assessed to cover all presently known important odorants from this type of animal production with adequate sensitivity and a time resolution of less than one minute. The sensitivity toward hydrogen sulfide is demonstrated to exhibit a pronounced humidity dependency, which can be included in the calibration procedure in order to achieve quantitative results for this compound. Application of the method at an experimental pig facility demonstrated strong temporal variations in emissions, including diurnal variation. Based on these first results, air exchange and animal activity are suggested to be of importance for emission rates of odorants. Highest emissions are seen for hydrogen sulfide and acetic acid, whereas key odorants are evaluated from tabulated odor threshold values to be hydrogen sulfide, methanethiol, 4-methylphenol, and butanoic acid. © 2010 American Chemical Society. Source

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