Dissemination of Salmonella enteritidis by experimentally-infected pigeons

Two groups of domestic pigeons (Columba livia) were experimentally infected orally with doses of 9.5 x10(7) and 9.5 x10(9) CFU/mL (group A and B, respectively) of a Salmonella Enteritidis (SE) strain isolated from chickens. None of the used doses caused mortality of the inoculated birds; however, the pathogen was successfully recovered from the liver and spleen of group B birds on day 7 post-inoculation (dpi). Pathogen shedding, as evaluated through cloacal swabs, occurred in both groups until the 14th day of observation (p <0.05). Among all fecal samples collected from group B (n=4), three different birds shed the pathogen in their feces, out of which two were positive on 3 dpi and one on 7 dpi. The same number of fecal samples was evaluated in group A and only one bird shed the pathogen, on 7 and 14 dpi. The concentration of the microorganism in the feces was lower in group A than any sample from Group B. Salmonella Enteritidis isolated from chickens, when inoculated in pigeons, may be recovered from feces, cloacal swabs and organs, and these birds may contaminate poultry causing economic losses as well as posing a risk to the public health

Isolation and Antimicrobial Resistance Profiles of Enterobacteria from Nestling Grey-Breasted Parakeets (Pyrrhura Griseipectus)

ABSTRACT The psittacine Pyrrhura griseipectus is a threatened species currently only found in Ceará State, Brazil. A microbiological survey was conducted to determine the composition of the enteric microbiota of this species, as well as the phenotypic profiles of antimicrobial susceptibility presented by the isolates. Cloacal swabs were collected from individual birds and submitted to microbiological processing. Antimicrobial susceptibility profiles were evaluated using the disk diffusion method. Bacteria of the genus Escherichia, Proteus, Citrobacter, Pantoea, Klebsiella, Enterobacter, Morganella, Hafnia, Enterobacter, and Serratia were isolated. The most frequently isolated species were Escherichia coli, Proteus mirabilis and Proteus vulgaris, corresponding to 36.1%, 26.4%, and 8.3%, respectively. Isolates were more frequently resistant to azithromycin and tetracycline, while Escherichia coli was the main species presenting multidrug resistance. In conclusion, free-living grey-breasted parakeets may harbor enterobacteria with high antimicrobial resistance rates

Experimental infection of Salmonella Enteritidis in quails submitted to forced molting by feed fasting

This study aimed at evaluating bacterial shedding, as detected in swabs, feces, and eggs of quails submitted to forced molting by feed fasting and experimentally infected with a Salmonella Enteritidis (SE) strain. In the experiment, 84 40-week-old Italian female quails were distributed in the following groups: FI (quails induced to molt by fasting and inoculated with Salmonella Enteritidis - SE); CI (quails fed with a laying diet and inoculated with SE); FNI (quails induced to molt by fasting and not inoculated with SE); and CNI (quails fed with a laying feed and not inoculated with SE). Feces, cloacal swabs, and eggs were collected on day 1, 3, 7 and 14 post-inoculation (dpi) and submitted to bacteriological analyses. All samples obtained from cloacal swabs were negative for SE. None of the quails of the non-inoculated groups (FNI and CNI) were positive for SE in the fecal samples. Among the inoculated quails, the FI group presented significantly higher (p< 0.05) SE shedding in the feces on 1 dpi than the CI group. On 4 dpi, no significant difference was observed (p< 0.05) in SE shedding between the inoculated quail groups. On 7 dpi, only the FI group shed SE in the feces, whereas on 14 dpi, none of the groups shed SE. According to the results, we concluded that quails submitted to molting by fasting have higher possibility of shedding SE in the feces

Isolation and Antimicrobial Resistance Profiles of Enterobacteria from Nestling Grey-Breasted Parakeets (Pyrrhura Griseipectus)

<div><p>ABSTRACT The psittacine Pyrrhura griseipectus is a threatened species currently only found in Ceará State, Brazil. A microbiological survey was conducted to determine the composition of the enteric microbiota of this species, as well as the phenotypic profiles of antimicrobial susceptibility presented by the isolates. Cloacal swabs were collected from individual birds and submitted to microbiological processing. Antimicrobial susceptibility profiles were evaluated using the disk diffusion method. Bacteria of the genus Escherichia, Proteus, Citrobacter, Pantoea, Klebsiella, Enterobacter, Morganella, Hafnia, Enterobacter, and Serratia were isolated. The most frequently isolated species were Escherichia coli, Proteus mirabilis and Proteus vulgaris, corresponding to 36.1%, 26.4%, and 8.3%, respectively. Isolates were more frequently resistant to azithromycin and tetracycline, while Escherichia coli was the main species presenting multidrug resistance. In conclusion, free-living grey-breasted parakeets may harbor enterobacteria with high antimicrobial resistance rates.</p></div

Recovery of Salmonella Gallinarum in the Organs of Experimentally-Inoculated Japanese Quails (Coturnix coturnix)

ABSTRACTSalmonellosis is an infection caused by specific or non specific serotypes of theSalmonella genus, responsible for losses in the poultry industry. Fowl typhoid, caused by S. Gallinarum (SG) is important because it causes elevated mortality in adult birds, leading to economic losses in the poultry industry. This study aimed at quantifying the number of viable SG cells in the liver, spleen, lung, cecum, and reproductive tract (ovary and testicles) of experimentally inoculated Japanese quails (Coturnix coturnix), as well as SG shedding in their feces. One hundred and two Japanese quails, with four months of age at the beginning of the experiment, were used. The birds were inoculated with three bacterial cultures containing different concentrations (6x104CFU/0.1mL, 2x105 CFU/0.4mL, or 5x106CFU/0.2mL) of SG resistant to nalidixic acid. On days 1, 4, 7, and 14 after the inoculation (dpi) individual cloacal swabs were collected from six birds per group, which were subsequently sacrificed for organ sampling. The swab samples were streaked directly on plates containing brilliant green agar and nalidixic acid (VBNal). Samples that were negative after 24h, were streaked again. The collected organs were individually macerated and transferred to buffered peptone water at 0.1%. The solutions were immediately diluted serially for CFU counting in VBNal. SG was successfully recovered from one quail, which was inoculated with 2x105 CFU/0.4mL, and from five quails of the group inoculated with 5x106CFU/0.2mL inoculum. All of the analyzed cloacal swab samples were negative. Therefore, this study demonstrated it was difficult to isolate SG from the analyzed organs and that it was not possible to recover thepathogen in the cloacal swabs collected from inoculated quails. These results may be explained by the absence of flagella in SG, inducing weak intestinal immune response in the beginning of the infection and preventing its isolation in cloacal swab samples. The low positivity rate of the analyzed organs may be due to the immune status of the euthanized birds, since the SG dissemination in the animal organism occurs mostly close to death, which was observed in the birds found dead during the experiment