The Experts below are selected from a list of 23457 Experts worldwide ranked by ideXlab platform
Freddy Haesebrouck - One of the best experts on this subject based on the ideXlab platform.
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The Impact of Deoxynivalenol on Pigeon Health: Occurrence in Feed, Toxicokinetics and Interaction with Salmonellosis
2016Co-Authors: Gunther Antonissen, Frank Pasmans, Freddy Haesebrouck, Roel Haesendonck, Mathias Devreese, Nathan Broekaert, Elin Verbrugghe, Sarah De Saeger, Kris Audenaert, Richard DucatelleAbstract:Seed-based pigeon diets could be expected to result in exposure of Pigeons to mycotoxins such as deoxynivalenol (DON). Ingestion of low to moderate contamination levels of DON may impair intestinal health, immune function and/or pathogen fitness, resulting in altered host-pathogen interactions and thus different outcome of infections. Here we demonstrate that DON was one of the most frequently detected mycotoxins in seed-based racing Pigeons feed, contaminating 5 out of 10 samples (range 177–1,466 μg/kg). Subsequently, a toxicokinetic analysis revealed a low absolute oral bioavailability (F) of DON in Pigeons (30.4%), which is comparable to other avian species. Furthermore, semi-quantitative analysis using high-resolution mass spectrometry revealed that DON-3α-sulphate is the major metabolite of DON in Pigeons after intravenous as well as oral administration. Following ingestion of DON contaminated feed, the intestinal epithelial cells are exposed to significant DON concentrations which eventually may affect intestinal translocation and colonization of bacteria. Feeding Pigeons a DON contaminated diet resulted in an increased percentage of Pigeons shedding Salmonella compared to birds fed control diet, 87 ± 17% versus 74 ± 13%, respectively. However, no impact of DON was observed on the Salmonella induced disease signs, organ lesions, faecal and organ Salmonella counts. The presented risk assessment indicates that Pigeons are frequently exposed to mycotoxins such as DON, which can affect the outcome of a Salmonella infection. The increasing number of Pigeons shedding Salmonella suggests that DON can promote the spread of the bacterium within pigeon populations.
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Induction of the carrier state in Pigeons infected with Salmonella enterica subspecies enterica serovar typhimurium PT99 by treatment with florfenicol: a matter of pharmacokinetics.
Antimicrobial Agents and Chemotherapy, 2008Co-Authors: Frank Pasmans, An Martel, Kris Baert, Alain Bousquet-melou, Ruben Lanckriet, Sandra De Boever, Filip Van Immerseel, Venessa Eeckhaut, Patrick De Backer, Freddy HaesebrouckAbstract:Paratyphoid caused by Salmonella enterica subsp. enterica serovar Typhimurium is the main bacterial disease in Pigeons. The ability of Salmonella serovar Typhimurium to persist intracellularly inside pigeon macrophages results in the development of chronic carriers, which maintain the infection in the flock. In this study, the effect of drinking-water medication with florfenicol on Salmonella infection in Pigeons was examined. The pharmacokinetics of florfenicol in Pigeons revealed a relatively high volume of distribution of 2.02 liters/kg of body weight and maximum concentrations in plasma higher than the MICs for the Salmonella strain used (4 microg/ml) but quick clearance of florfenicol due to a short half-life of 1.73 h. Together with highly variable bioavailability and erratic drinking-water uptake, these parameters resulted in the inability to reach a steady-state concentration through the continuous administration of florfenicol in the drinking water. Florfenicol was capable of reducing only moderately the number of intracellular salmonellae in infected pigeon macrophages in vitro. Only at high extracellular concentrations (>16 microg/ml) was a more-than-10-fold reduction of the number of intracellular bacteria noticed. Florfenicol treatment of Pigeons via the drinking water from 2 days after experimental inoculation with Salmonella serovar Typhimurium until euthanasia at 16 days postinoculation resulted in a reduction of Salmonella shedding and an improvement in the fecal consistency. However, internal organs in florfenicol-treated Pigeons were significantly more heavily colonized than those in untreated Pigeons. In conclusion, the oral application of florfenicol for the treatment of pigeon paratyphoid contributes to the development of carrier animals through sub-MIC concentrations in plasma that do not inhibit intracellular persistency.
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host adaptation of pigeon isolates of salmonella enterica subsp enterica serovar typhimurium variant copenhagen phage type 99 is associated with enhanced macrophage cytotoxicity
Infection and Immunity, 2003Co-Authors: Frank Pasmans, An Martel, Filip Van Immerseel, Marc Heyndrickx, C Godard, C Wildemauwe, Richard Ducatelle, Freddy HaesebrouckAbstract:Phage type 99 of Salmonella enterica subsp. enterica serovar Typhimurium variant Copenhagen strains isolated from Pigeons were examined for the presence of genotypic and phenotypic characteristics. The pulsed-field gel electrophoresis patterns obtained with XbaI and BlnI from 38 pigeon strains were compared with those obtained from 89 porcine, poultry, and human strains of variant Copenhagen. Identical patterns with XbaI and four closely related patterns with BlnI were obtained with the pigeon strains, whereas 16 XbaI patterns were found with the other strains. The XbaI patterns of the pigeon strains showed a low genetic similarity to the patterns of the porcine, poultry, and human strains and invariably showed a low-molecular-weight band that was absent in the majority of the other strains. The virulence genes shdA, spvR, pefA, sopE, and spvB were uniformly present in six pigeon isolates representing the genetic diversity found with BlnI. These six pigeon-derived strains were highly cytotoxic for pigeon macrophages compared to three porcine strains. After experimental infection of Pigeons with a pigeon strain, clinical symptoms, fecal shedding, and colonization of internal organs were more pronounced than those after infection with a porcine strain. These data suggest that the phage type 99 strains used in this study are highly adapted to Pigeons and should be classified as a host-restricted lineage of the serovar Typhimurium.
Frank Pasmans - One of the best experts on this subject based on the ideXlab platform.
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The Impact of Deoxynivalenol on Pigeon Health: Occurrence in Feed, Toxicokinetics and Interaction with Salmonellosis
2016Co-Authors: Gunther Antonissen, Frank Pasmans, Freddy Haesebrouck, Roel Haesendonck, Mathias Devreese, Nathan Broekaert, Elin Verbrugghe, Sarah De Saeger, Kris Audenaert, Richard DucatelleAbstract:Seed-based pigeon diets could be expected to result in exposure of Pigeons to mycotoxins such as deoxynivalenol (DON). Ingestion of low to moderate contamination levels of DON may impair intestinal health, immune function and/or pathogen fitness, resulting in altered host-pathogen interactions and thus different outcome of infections. Here we demonstrate that DON was one of the most frequently detected mycotoxins in seed-based racing Pigeons feed, contaminating 5 out of 10 samples (range 177–1,466 μg/kg). Subsequently, a toxicokinetic analysis revealed a low absolute oral bioavailability (F) of DON in Pigeons (30.4%), which is comparable to other avian species. Furthermore, semi-quantitative analysis using high-resolution mass spectrometry revealed that DON-3α-sulphate is the major metabolite of DON in Pigeons after intravenous as well as oral administration. Following ingestion of DON contaminated feed, the intestinal epithelial cells are exposed to significant DON concentrations which eventually may affect intestinal translocation and colonization of bacteria. Feeding Pigeons a DON contaminated diet resulted in an increased percentage of Pigeons shedding Salmonella compared to birds fed control diet, 87 ± 17% versus 74 ± 13%, respectively. However, no impact of DON was observed on the Salmonella induced disease signs, organ lesions, faecal and organ Salmonella counts. The presented risk assessment indicates that Pigeons are frequently exposed to mycotoxins such as DON, which can affect the outcome of a Salmonella infection. The increasing number of Pigeons shedding Salmonella suggests that DON can promote the spread of the bacterium within pigeon populations.
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mycoplasma columbinum isolated from a racing pigeon columba livia with arthritis
Journal of Avian Medicine and Surgery, 2014Co-Authors: Tom Hellebuyck, Frank Pasmans, An Garmyn, Lien De Cooman, Filip Boyen, An MartelAbstract:A juvenile racing pigeon (Columba livia) was presented with drooping of the wing and inability to fly. On physical examination, the right shoulder joint was swollen. The pigeon was euthanatized and submitted for necropsy. An excessive amount of fibrin was present in the canalis triosseus with severe arthritis of the affected shoulder joint. A pure growth of Mycoplasma-like colonies was obtained on microbiological culture of the shoulder joint. A 16S ribosomal RNA gene-specific polymerase chain reaction assay was performed on the isolate and revealed 100% similarity with Mycoplasma columbinum. Although infectious arthritis in homing Pigeons is primarily associated with paratyphoid and Streptococcus gallolyticus infection, clinical practitioners should consider the potential role of Mycoplasma columbinum in arthritis in Pigeons.
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Induction of the carrier state in Pigeons infected with Salmonella enterica subspecies enterica serovar typhimurium PT99 by treatment with florfenicol: a matter of pharmacokinetics.
Antimicrobial Agents and Chemotherapy, 2008Co-Authors: Frank Pasmans, An Martel, Kris Baert, Alain Bousquet-melou, Ruben Lanckriet, Sandra De Boever, Filip Van Immerseel, Venessa Eeckhaut, Patrick De Backer, Freddy HaesebrouckAbstract:Paratyphoid caused by Salmonella enterica subsp. enterica serovar Typhimurium is the main bacterial disease in Pigeons. The ability of Salmonella serovar Typhimurium to persist intracellularly inside pigeon macrophages results in the development of chronic carriers, which maintain the infection in the flock. In this study, the effect of drinking-water medication with florfenicol on Salmonella infection in Pigeons was examined. The pharmacokinetics of florfenicol in Pigeons revealed a relatively high volume of distribution of 2.02 liters/kg of body weight and maximum concentrations in plasma higher than the MICs for the Salmonella strain used (4 microg/ml) but quick clearance of florfenicol due to a short half-life of 1.73 h. Together with highly variable bioavailability and erratic drinking-water uptake, these parameters resulted in the inability to reach a steady-state concentration through the continuous administration of florfenicol in the drinking water. Florfenicol was capable of reducing only moderately the number of intracellular salmonellae in infected pigeon macrophages in vitro. Only at high extracellular concentrations (>16 microg/ml) was a more-than-10-fold reduction of the number of intracellular bacteria noticed. Florfenicol treatment of Pigeons via the drinking water from 2 days after experimental inoculation with Salmonella serovar Typhimurium until euthanasia at 16 days postinoculation resulted in a reduction of Salmonella shedding and an improvement in the fecal consistency. However, internal organs in florfenicol-treated Pigeons were significantly more heavily colonized than those in untreated Pigeons. In conclusion, the oral application of florfenicol for the treatment of pigeon paratyphoid contributes to the development of carrier animals through sub-MIC concentrations in plasma that do not inhibit intracellular persistency.
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host adaptation of pigeon isolates of salmonella enterica subsp enterica serovar typhimurium variant copenhagen phage type 99 is associated with enhanced macrophage cytotoxicity
Infection and Immunity, 2003Co-Authors: Frank Pasmans, An Martel, Filip Van Immerseel, Marc Heyndrickx, C Godard, C Wildemauwe, Richard Ducatelle, Freddy HaesebrouckAbstract:Phage type 99 of Salmonella enterica subsp. enterica serovar Typhimurium variant Copenhagen strains isolated from Pigeons were examined for the presence of genotypic and phenotypic characteristics. The pulsed-field gel electrophoresis patterns obtained with XbaI and BlnI from 38 pigeon strains were compared with those obtained from 89 porcine, poultry, and human strains of variant Copenhagen. Identical patterns with XbaI and four closely related patterns with BlnI were obtained with the pigeon strains, whereas 16 XbaI patterns were found with the other strains. The XbaI patterns of the pigeon strains showed a low genetic similarity to the patterns of the porcine, poultry, and human strains and invariably showed a low-molecular-weight band that was absent in the majority of the other strains. The virulence genes shdA, spvR, pefA, sopE, and spvB were uniformly present in six pigeon isolates representing the genetic diversity found with BlnI. These six pigeon-derived strains were highly cytotoxic for pigeon macrophages compared to three porcine strains. After experimental infection of Pigeons with a pigeon strain, clinical symptoms, fecal shedding, and colonization of internal organs were more pronounced than those after infection with a porcine strain. These data suggest that the phage type 99 strains used in this study are highly adapted to Pigeons and should be classified as a host-restricted lineage of the serovar Typhimurium.
An Martel - One of the best experts on this subject based on the ideXlab platform.
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mycoplasma columbinum isolated from a racing pigeon columba livia with arthritis
Journal of Avian Medicine and Surgery, 2014Co-Authors: Tom Hellebuyck, Frank Pasmans, An Garmyn, Lien De Cooman, Filip Boyen, An MartelAbstract:A juvenile racing pigeon (Columba livia) was presented with drooping of the wing and inability to fly. On physical examination, the right shoulder joint was swollen. The pigeon was euthanatized and submitted for necropsy. An excessive amount of fibrin was present in the canalis triosseus with severe arthritis of the affected shoulder joint. A pure growth of Mycoplasma-like colonies was obtained on microbiological culture of the shoulder joint. A 16S ribosomal RNA gene-specific polymerase chain reaction assay was performed on the isolate and revealed 100% similarity with Mycoplasma columbinum. Although infectious arthritis in homing Pigeons is primarily associated with paratyphoid and Streptococcus gallolyticus infection, clinical practitioners should consider the potential role of Mycoplasma columbinum in arthritis in Pigeons.
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Racing Pigeons : a reservoir for nitro-imidazole-resistant Trichomonas gallinae
'American Society of Parasitologists', 2014Co-Authors: Rouffaer Lieze, Adriaensen Connie, De Boeck Cindy, Claerebout Edwin, An MartelAbstract:Trichomonas gallinae, the cause of avian trichomonosis, is most commonly found in the order Columbiformes. Racing Pigeons are often treated preventively with nitro-imidazoles which could result in the emergence of resistant isolates, and these isolates can be a treath to wildlife when exchanges occur. The sequence type of 16 T. gallinae isolates obtained from racing Pigeons and 15 isolates from wild Pigeons was determined based on the ITS1/5.8S rRNA/ITS2 region sequence. In addition, the resistance profiles of these isolates against five different nitro-imidazoles (metronidazole, dimetridazole, ronidazole, tinidazole and carnidazole) were determined. Two different Trichomonas sequence types were isolated. Sequence type A isolates were recovered from racing and wild Pigeons, in contrast to sequence type B which was only isolated from wild Pigeons. Isolates with sequence type B were all susceptible to the tested nitro-imidazoles, except for tinidazole-resistance in 3 isolates. Resistance to the nitro-imidazoles was observed more frequently in isolates obtained from racing Pigeons than from wild Pigeons, with most isolates belonging to sequence type A. A higher percentage of the sequence type A isolated from racing Pigeons, in comparison with those isolated from the wild Pigeons, were resistant to the nitro-imidazoles and displayed higher mean lethal concentration (MLC) values. Two isolates belonging to sequence type A, 1 recovered from a racing pigeon and 1 from a wild pigeon, displayed a similar resistance pattern, suggesting a potential exchange of resistant isolates between racing Pigeons and wild Pigeons
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Induction of the carrier state in Pigeons infected with Salmonella enterica subspecies enterica serovar typhimurium PT99 by treatment with florfenicol: a matter of pharmacokinetics.
Antimicrobial Agents and Chemotherapy, 2008Co-Authors: Frank Pasmans, An Martel, Kris Baert, Alain Bousquet-melou, Ruben Lanckriet, Sandra De Boever, Filip Van Immerseel, Venessa Eeckhaut, Patrick De Backer, Freddy HaesebrouckAbstract:Paratyphoid caused by Salmonella enterica subsp. enterica serovar Typhimurium is the main bacterial disease in Pigeons. The ability of Salmonella serovar Typhimurium to persist intracellularly inside pigeon macrophages results in the development of chronic carriers, which maintain the infection in the flock. In this study, the effect of drinking-water medication with florfenicol on Salmonella infection in Pigeons was examined. The pharmacokinetics of florfenicol in Pigeons revealed a relatively high volume of distribution of 2.02 liters/kg of body weight and maximum concentrations in plasma higher than the MICs for the Salmonella strain used (4 microg/ml) but quick clearance of florfenicol due to a short half-life of 1.73 h. Together with highly variable bioavailability and erratic drinking-water uptake, these parameters resulted in the inability to reach a steady-state concentration through the continuous administration of florfenicol in the drinking water. Florfenicol was capable of reducing only moderately the number of intracellular salmonellae in infected pigeon macrophages in vitro. Only at high extracellular concentrations (>16 microg/ml) was a more-than-10-fold reduction of the number of intracellular bacteria noticed. Florfenicol treatment of Pigeons via the drinking water from 2 days after experimental inoculation with Salmonella serovar Typhimurium until euthanasia at 16 days postinoculation resulted in a reduction of Salmonella shedding and an improvement in the fecal consistency. However, internal organs in florfenicol-treated Pigeons were significantly more heavily colonized than those in untreated Pigeons. In conclusion, the oral application of florfenicol for the treatment of pigeon paratyphoid contributes to the development of carrier animals through sub-MIC concentrations in plasma that do not inhibit intracellular persistency.
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Modelling Aspergillus fumigatus infections in racing Pigeons (Columba livia domestica)
'Informa UK Limited', 2008Co-Authors: Beernaert Lies, Pasmans Frank, Haesebrouck Freddy, An MartelAbstract:In vivo modelling of aspergillosis in birds allows the evaluation of control measures and the study of host-pathogen interactions. In this study the impact of the use of different inoculation routes and immunosuppression on the Course of all infection with Aspergillus fumigatus in racing Pigeons (Columba livia domestica) was examined. A fumigatus conidia were inoculated in the thoracic air sac, lung or trachea in immunocompetent or immunosuppressed pigeon squabs. Immunosuppression was Induced by three dexamethasone injections before Inoculation. Mortality in the A. fumigatus-inoculated groups varied between 1/4 and 4/4. The highest and more acute mortality was seen in immunocompetent Pigeons inoculated in the thoracic air sac and in Pigeons inoculated in the thoracic air sac or lung after immunosuppression. Pigeons Inoculated in the lung or inoculated intratracheally after immunosuppression developed an aspergillosis infection with a slower course of disease and more prominent clinical symptoms. Using microsatellite length polymorphism, it was confirmed that all mycoses were caused by the inoculated strain except for one isolate in a dexamethasone-treated pigeon. In conclusion, inoculation in the lung is selected as the preferred model for chronic aspergillosis in Pigeons, and inoculation in the thoracic air sac as the preferred model for acute aspergillosis. The use of immunosuppressed birds seems to be contra-indicated due to the risk of opportunistic infections
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host adaptation of pigeon isolates of salmonella enterica subsp enterica serovar typhimurium variant copenhagen phage type 99 is associated with enhanced macrophage cytotoxicity
Infection and Immunity, 2003Co-Authors: Frank Pasmans, An Martel, Filip Van Immerseel, Marc Heyndrickx, C Godard, C Wildemauwe, Richard Ducatelle, Freddy HaesebrouckAbstract:Phage type 99 of Salmonella enterica subsp. enterica serovar Typhimurium variant Copenhagen strains isolated from Pigeons were examined for the presence of genotypic and phenotypic characteristics. The pulsed-field gel electrophoresis patterns obtained with XbaI and BlnI from 38 pigeon strains were compared with those obtained from 89 porcine, poultry, and human strains of variant Copenhagen. Identical patterns with XbaI and four closely related patterns with BlnI were obtained with the pigeon strains, whereas 16 XbaI patterns were found with the other strains. The XbaI patterns of the pigeon strains showed a low genetic similarity to the patterns of the porcine, poultry, and human strains and invariably showed a low-molecular-weight band that was absent in the majority of the other strains. The virulence genes shdA, spvR, pefA, sopE, and spvB were uniformly present in six pigeon isolates representing the genetic diversity found with BlnI. These six pigeon-derived strains were highly cytotoxic for pigeon macrophages compared to three porcine strains. After experimental infection of Pigeons with a pigeon strain, clinical symptoms, fecal shedding, and colonization of internal organs were more pronounced than those after infection with a porcine strain. These data suggest that the phage type 99 strains used in this study are highly adapted to Pigeons and should be classified as a host-restricted lineage of the serovar Typhimurium.
George M Church - One of the best experts on this subject based on the ideXlab platform.
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complete mitochondrial genomes of living and extinct Pigeons revise the timing of the columbiform radiation
BMC Evolutionary Biology, 2016Co-Authors: Andre E R Soares, Ben J Novak, James Haile, Tim H Heupink, Jon Fjeldsa, Thomas M P Gilbert, Hendrik N Poinar, George M ChurchAbstract:Pigeons and doves (Columbiformes) are one of the oldest and most diverse extant lineages of birds. However, the nature and timing of the group’s evolutionary radiation remains poorly resolved, despite recent advances in DNA sequencing and assembly and the growing database of pigeon mitochondrial genomes. One challenge has been to generate comparative data from the large number of extinct pigeon lineages, some of which are morphologically unique and therefore difficult to place in a phylogenetic context. We used ancient DNA and next generation sequencing approaches to assemble complete mitochondrial genomes for eleven Pigeons, including the extinct Ryukyu wood pigeon (Columba jouyi), the thick-billed ground dove (Alopecoenas salamonis), the spotted green pigeon (Caloenas maculata), the Rodrigues solitaire (Pezophaps solitaria), and the dodo (Raphus cucullatus). We used a Bayesian approach to infer the evolutionary relationships among 24 species of living and extinct Pigeons and doves. Our analyses indicate that the earliest radiation of the Columbidae crown group most likely occurred during the Oligocene, with continued divergence of major clades into the Miocene, suggesting that diversification within the Columbidae occurred more recently than has been reported previously.
Filip Van Immerseel - One of the best experts on this subject based on the ideXlab platform.
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Induction of the carrier state in Pigeons infected with Salmonella enterica subspecies enterica serovar typhimurium PT99 by treatment with florfenicol: a matter of pharmacokinetics.
Antimicrobial Agents and Chemotherapy, 2008Co-Authors: Frank Pasmans, An Martel, Kris Baert, Alain Bousquet-melou, Ruben Lanckriet, Sandra De Boever, Filip Van Immerseel, Venessa Eeckhaut, Patrick De Backer, Freddy HaesebrouckAbstract:Paratyphoid caused by Salmonella enterica subsp. enterica serovar Typhimurium is the main bacterial disease in Pigeons. The ability of Salmonella serovar Typhimurium to persist intracellularly inside pigeon macrophages results in the development of chronic carriers, which maintain the infection in the flock. In this study, the effect of drinking-water medication with florfenicol on Salmonella infection in Pigeons was examined. The pharmacokinetics of florfenicol in Pigeons revealed a relatively high volume of distribution of 2.02 liters/kg of body weight and maximum concentrations in plasma higher than the MICs for the Salmonella strain used (4 microg/ml) but quick clearance of florfenicol due to a short half-life of 1.73 h. Together with highly variable bioavailability and erratic drinking-water uptake, these parameters resulted in the inability to reach a steady-state concentration through the continuous administration of florfenicol in the drinking water. Florfenicol was capable of reducing only moderately the number of intracellular salmonellae in infected pigeon macrophages in vitro. Only at high extracellular concentrations (>16 microg/ml) was a more-than-10-fold reduction of the number of intracellular bacteria noticed. Florfenicol treatment of Pigeons via the drinking water from 2 days after experimental inoculation with Salmonella serovar Typhimurium until euthanasia at 16 days postinoculation resulted in a reduction of Salmonella shedding and an improvement in the fecal consistency. However, internal organs in florfenicol-treated Pigeons were significantly more heavily colonized than those in untreated Pigeons. In conclusion, the oral application of florfenicol for the treatment of pigeon paratyphoid contributes to the development of carrier animals through sub-MIC concentrations in plasma that do not inhibit intracellular persistency.
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host adaptation of pigeon isolates of salmonella enterica subsp enterica serovar typhimurium variant copenhagen phage type 99 is associated with enhanced macrophage cytotoxicity
Infection and Immunity, 2003Co-Authors: Frank Pasmans, An Martel, Filip Van Immerseel, Marc Heyndrickx, C Godard, C Wildemauwe, Richard Ducatelle, Freddy HaesebrouckAbstract:Phage type 99 of Salmonella enterica subsp. enterica serovar Typhimurium variant Copenhagen strains isolated from Pigeons were examined for the presence of genotypic and phenotypic characteristics. The pulsed-field gel electrophoresis patterns obtained with XbaI and BlnI from 38 pigeon strains were compared with those obtained from 89 porcine, poultry, and human strains of variant Copenhagen. Identical patterns with XbaI and four closely related patterns with BlnI were obtained with the pigeon strains, whereas 16 XbaI patterns were found with the other strains. The XbaI patterns of the pigeon strains showed a low genetic similarity to the patterns of the porcine, poultry, and human strains and invariably showed a low-molecular-weight band that was absent in the majority of the other strains. The virulence genes shdA, spvR, pefA, sopE, and spvB were uniformly present in six pigeon isolates representing the genetic diversity found with BlnI. These six pigeon-derived strains were highly cytotoxic for pigeon macrophages compared to three porcine strains. After experimental infection of Pigeons with a pigeon strain, clinical symptoms, fecal shedding, and colonization of internal organs were more pronounced than those after infection with a porcine strain. These data suggest that the phage type 99 strains used in this study are highly adapted to Pigeons and should be classified as a host-restricted lineage of the serovar Typhimurium.
