Dataset Information

Detection and quantification of 14 Campylobacter species in pet dogs reveals an increase in species richness in feces of diarrheic animals.

ABSTRACT:

Background

The genus Campylobacter includes many species, some of which are known human and animal pathogens. Even though studies have repeatedly identified domestic dogs as a risk factor for human campylobacteriosis, our understanding of Campylobacter ecology in this reservoir is limited. Work to date has focused primarily on a limited number of species using culture-based methods. To expand our understanding of Campylobacter ecology in dogs, a collection of fecal samples from 70 healthy and 65 diarrheic pet dogs were examined for the presence and levels of 14 Campylobacter species using quantitative PCR.

Results

It was found that 58% of healthy dogs and 97% of diarrheic dogs shed detectable levels of Campylobacter spp., with C. coli, C. concisus, C. fetus, C. gracilis, C. helveticus, C. jejuni, C. lari, C. mucosalis, C. showae, C. sputorum and C. upsaliensis levels significantly higher in the diarrheic population. Levels of individual Campylobacter species detected ranged from 103 to 108 organisms per gram of feces. In addition, many individual samples contained multiple species of Campylobacter, with healthy dogs carrying from 0-7 detectable species while diarrheic dogs carried from 0-12 detectable species.

Conclusions

These findings represent the largest number of Campylobacter species specifically tested for in animals and is the first report to determine quantifiable levels of Campylobacter being shed from dogs. This study demonstrates that domestic dogs can carry a wide range of Campylobacter species naturally and that there is a notable increase in species richness detectable in the diarrheic population. With several of the detected Campylobacter species known or emerging pathogens, these results are relevant to both ecological and public health discussions.

SUBMITTER: Chaban B

PROVIDER: S-EPMC2848019 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Publications

Detection and quantification of 14 Campylobacter species in pet dogs reveals an increase in species richness in feces of diarrheic animals.

Chaban Bonnie B Ngeleka Musangu M Hill Janet E JE

BMC microbiology 20100310

<h4>Background</h4>The genus Campylobacter includes many species, some of which are known human and animal pathogens. Even though studies have repeatedly identified domestic dogs as a risk factor for human campylobacteriosis, our understanding of Campylobacter ecology in this reservoir is limited. Work to date has focused primarily on a limited number of species using culture-based methods. To expand our understanding of Campylobacter ecology in dogs, a collection of fecal samples from 70 health ...[more]

PMID: 20219122

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Project description:BackgroundSmall-animal PET imaging is an important tool in preclinical oncology. This study evaluated the ability of a clinical SiPM-PET camera to image several rats simultaneously and to perform quantification data analysis.MethodsIntrinsic spatial resolution was measured using 18F line sources, and image quality was assessed using a NEMA NU 4-2018 phantom. Quantification was evaluated using a fillable micro-hollow sphere phantom containing 4 spheres of different sizes (ranging from 3.95 to 7.86 mm). Recovery coefficients were computed for the maximum (Amax) and the mean (A50) pixel values measured on a 50% isocontour drawn on each sphere. Measurements were performed first with the phantom placed in the centre of the field of view and then in the off-centre position with the presence of three scattering sources to simulate the acquisition of four animals simultaneously. Quantification accuracy was finally validated using four 3D-printed phantoms mimicking rats with four subcutaneous tumours each. All experiments were performed for both 18F and 68Ga radionuclides.ResultsRadial spatial resolutions measured using the PSF reconstruction algorithm were 1.80 mm and 1.78 mm for centred and off-centred acquisitions, respectively. Spill-overs in air and water and uniformity computed with the NEMA phantom centred in the FOV were 0.05, 0.1 and 5.55% for 18F and 0.08, 0.12 and 2.81% for 68Ga, respectively. Recovery coefficients calculated with the 18F-filled micro-hollow sphere phantom for each sphere varied from 0.51 to 1.43 for Amax and from 0.40 to 1.01 for A50. These values decreased from 0.28 to 0.92 for Amax and from 0.22 to 0.66 for A50 for 68 Ga acquisition. The results were not significantly different when imaging phantoms in the off-centre position with 3 scattering sources. Measurements performed with the four 3D-printed phantoms showed a good correlation between theoretical and measured activity in simulated tumours, with r2 values of 0.99 and 0.97 obtained for 18F and 68Ga, respectively.ConclusionWe found that the clinical SiPM-based PET system was close to that obtained with a dedicated small-animal PET device. This study showed the ability of such a system to image four rats simultaneously and to perform quantification analysis for radionuclides commonly used in oncology.

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Dataset Information

Detection and quantification of 14 Campylobacter species in pet dogs reveals an increase in species richness in feces of diarrheic animals.

Background

Results

Conclusions

Publications

Detection and quantification of 14 Campylobacter species in pet dogs reveals an increase in species richness in feces of diarrheic animals.

Similar Datasets

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