Parrots in captivity are frequently affected by
Parrots are among the most endangered group of birds worldwide, and 15 of the 84 Brazilian species are classified as being vulnerable or critically endangered [
The Hyacinth macaw and Lear’s macaw are well-known flagship species that have suffered heavily owing to the destruction of habitat and illegal trade. A number of studies aimed at promoting their recovery have been performed and actions taken; however, they are still classified as endangered species and face severe threats to their long-term survival [
Studies have established that the intestinal flora of most species of healthy captive psittacines is composed essentially of Gram-positive bacteria [
The purpose of this study was to test cloacal samples from asymptomatic free-living nestlings (Blue-fronted Amazon parrots as well as Hyacinth and Lear’s macaws) to determine if they could be carriers of recognized
The samples of this study were collected during field surveys of the nestlings of Hyacinth macaws and Blue-fronted Amazon parrots in the Pantanal (wetlands) region of the Refúgio Ecológico Caiman and neighboring farms (19°58′S, 56°24′W) in Mato Grosso do Sul State, and of Lear’s macaws at the Estação Ecológica de Canudos (09°53′48′′S, 39°01′35′′W) in the Caatinga (semi-arid) of the Bahia State. Cloacal swabs (CultureSwab Sterile, DIFCO Becton Dickenson and Company, Sparks, Maryland, USA) were moistened with care using a sterile saline solution so as not to contaminate the swab during insertion in the cloaca. All chicks had no evident signs of disease (soiled vent, emaciation, prostration, or delays in development according to their estimated age). In total, 44 samples were obtained, of which 10 were from Hyacinths, 13 from Lear’s, and 21 from Blue-fronted Amazon parrots.
The swabs were refrigerated up to processing at which point they were aerobically incubated in BHI broth (Brain Heart Infusion, DIFCO) for 24 hours at 37°C. They were then streaked onto MacConkey (DIFCO) agar plates and incubated for another 24 hours at 37°C. Bacteria were identified using a specific enterobacteria identification kit (Newprov, Pinhais, Paraná, Brazil) and stored at −20°C. Isolates were tested using polymerase chain reaction (PCR) (Table
Cloacal swab samples from free-ranging parrot nestlings tested for select
Species | Number of positive samples/total number of samples |
|
|
|
|
|
|
|
|
|
---|---|---|---|---|---|---|---|---|---|---|
|
7/21 | − | − | − | − | + | − | − | − | − |
|
1/21 | − | − | + | − | + | − | − | − | − |
|
1/21 | − | − | − | − | + | − | + | − | − |
|
1/21 | − | − | − | − | + | + | − | − | − |
|
1/21 | − | − | + | − | + | − | − | − | + |
|
3/10 | − | − | − | − | + | − | − | − | − |
|
1/13 | + | − | − | − | − | − | − | − | − |
Virulence factors and gene sequences tested by polymerase chain reaction (PCR) according to the described references.
Virulence factor | Sequence (5′–3′) | Reference |
---|---|---|
Intimin |
F-CTGAACGGCGATTACGCGAA |
Aranda et al. [ |
R-CGAGACGATACGATCCAG | ||
Bundle forming pili |
F-AATGGTGCTTGCGCTTGCTGC | Aranda et al. [ |
R-GCCGCTTTATCCAACCTGGTA | ||
S fimbrial adhesin |
F-CTCCGGAGAACTGGGTGCATCTTAC | Yamamoto et al. [ |
R-CGGAGGAGTAAT TACAAACCT GGCA | ||
P fimbrial adhesin |
F-GCAACAGCAACGCTGGTTGCATCAT | Yamamoto et al. [ |
R-AGAGAGAGCCACTCTTATACGGACA | ||
Increased serum survival |
F-AGAGAGAGCCACTCTTATACGGACA | Ewers et al. [ |
R-CTATTGTGAGCAATATACA | ||
Aerobactin |
F-TACCGGATTGTCATATGCAGACCGT | Yamamoto et al. [ |
R-AATATCTTCCTCCAGTCCGGAGAAG | ||
Temperature-sensitive hemagglutinin |
F-ACTATTCTCTGCAGGAAGTC | Ewers et al. [ |
R-CTTCCGATGTTCTGAACGT | ||
Alpha hemolysin |
F-AACAAGGATAAGCACTGTTCTGGCT | Yamamoto et al. [ |
R-ACCATATAAGCGGTCATTCCCGTCA | ||
Cytotoxic necrotizing factor |
F-AAGATGGAGTTTCCTATGCAGGAG | Yamamoto et al. [ |
R-CATTCAGAGTCCTGCCCTCATTATT |
EPEC have the ability to cause lesions on the intestinal mucosa, leading to severe diarrhea. This process is initiated by adherence to the epithelial cell membrane and is mediated by the adhesin intimin (encoded by the
One of the samples in this study was characterized as an atypical EPEC. These strains are frequently isolated from domestic animals. There are few reports of the presence of atypical EPEC in birds, especially the isolates obtained from poultry [
APEC and UPEC share several genes that encode virulence factors such as P fimbrial adhesin (
Siderophores, such as aerobactin (
In this investigation, 2 samples were positive for the
Other genes such as the
This research also found 1 positive sample for the
Even though the sample numbers were too small to reach definite conclusions, we observed differences in the presence of virulence factors among the different species. APEC/UPEC genes were found mostly in species that usually nest on trees and live in a tropical climate (at least in this studied area, for the species
Although previous studies showed that some virulence factors are indeed involved in clinical cases of colibacillosis in psittacines [
The concept of disease is considered the result of an interactive relationship among the causative agent, the animal, and environmental factors [
The results presented here are also important for the future conservation of the 2 endangered species (
In conclusion, to our knowledge, this is the first study that tested
The authors wish to thank The World Parrot Trust for supporting activities with the Lear’s macaw Project. Additional thanks to Fundação O Boticário, Fundação Neotrópica do Brasil, Fundação Biodiversitas, Instituto Arara Azul, Universidade Anhanguera-Uniderp, R. E. Caiman, Fundação Toyota do Brasil, Parrots International, Bradesco capitalização, and other sponsors of the Projeto Arara Azul, Projeto Papagaio-verdadeiro e Projeto Arara-de-Lear. This study was funded by FAPESP Grant no. 2010/51015-0 and Grant no. 2011/50375-5.