Dogs In Chile Research Articles

A preliminary report on critical antimicrobial resistance in Escherichia coli, Enterococcus faecalis, and Enterococcus faecium strains isolated from healthy dogs in Chile during 2021-2022

Antimicrobial Resistance (AMR) represents one of the main current threats to global public health; where production animals, companion animals, humans, and the environment play a significant role in its dissemination. However, little attention has been given to companion animals as reservoirs and disseminators of relevant antimicrobial resistant bacteria, especially in South American countries such as Chile. For this reason, this research aimed to estimate the prevalence of AMR to different critical antibiotics at a screening level in commensal bacteria such as E. coli and Enterococcus spp., isolated from healthy pet dogs in the Metropolitan Region of Chile, studying their geographical distribution and evaluating associations of phenotypic resistance to different antibiotics. Thus, in E. coli we detected AMR to all critical drugs assessed, including 34.1% to amoxicillin, 20.1% to colistin, 15.7% to enrofloxacin, and 9.2% to cefotaxime. On the other hand, AMR prevalence in E. faecalis was 8.1% for ampicillin and 3.4% for vancomycin; while for E. faecium the AMR prevalence was 19.1% for ampicillin and 10.2% for vancomycin. Additionally, significant differences in prevalence of the different possible AMR were detected according to their geographical distribution, suggesting the existence of various risk factors and stressing the need to establish mitigation measures specific to the differences identified.

Phenotypic and genotypic antimicrobial resistance in Escherichia coli strains isolated from household dogs in Chile.

Antimicrobial resistance (AMR) is a major threat to animal and public health worldwide; consequently, several AMR surveillances programs have been implemented internationally in both human and veterinary medicine, including indicator bacteria such as Escherichia coli. However, companion animals are not typically included in these surveillance programs. Nevertheless, there have been reports of increasing levels of antimicrobial resistance in E. coli strains isolated from dogs worldwide. In Chile, there is limited information available on AMR in E. coli isolated from companion animals, which prevents the establishment of objective prevention and control measures. For this reason, the aim of this study was to characterize the phenotypic and genotypic AMR of E. coli strains isolated from healthy household dogs in Chile. For this purpose, a multi-stage sampling was carried out in the Metropolitan Region of Chile, obtaining samples from 600 healthy dogs. These samples were processed using traditional bacteriology and molecular techniques to isolate E. coli strains. We assessed the minimal inhibitory concentration of 17 antimicrobials and conducted a search of six antimicrobial resistance genes, as well as class 1 and 2 integrons, in the isolated strains. Two-hundred and twenty-four strains of E. coli were recovered, and 96.9% (n = 217) showed resistance to at least one drug and only 3.1% (n = 7) were susceptible to all analyzed antimicrobials. Most strains were resistant to cefalexin (91.5%, n = 205, 1st-generation cephalosporin), followed by ampicillin (68.3%, n = 153) and cefpodoxime (31.3%, n = 70, 3rd-generation cephalosporin). Moreover, 24.1% (n = 54) tested positive for extended-spectrum-β-lactamases and 34.4% (n = 77) were multidrug resistant. As for the AMR genes, the most detected was qnrB (28.1%, n = 63), followed by blaCTX-M (22.3%, n = 50), and blaTEM-1 (19.6%, n = 44). Additionally, 16.1% (n = 36) harbored class 1 integrons. Our study shows that E. coli strains isolated from healthy household dogs exhibit resistance to several relevant drugs and also antimicrobial resistance genes considered critical for human health. These results can be used as a starting point for the prevention and control of antimicrobial resistance from companion animals. This background should be considered when formulating future resistance surveillance programs or control plans in which companion animals must be included.

Mapping the distribution and risk factors of Anaplasmataceae in wild and domestic canines in Chile and their association with Rhipicephalus sanguineus species complex lineages

Anaplasma platys and Ehrlichia canis are members of the Anaplasmataceae family that cause disease in dogs and are mainly transmitted by Rhipicephalus sanguineus species group ticks. We performed a cross-sectional study on these pathogens across six bioclimatic regions of Chile, including 719 free-ranging rural dogs, 132 Andean foxes (Lycalopex culpaeus), and 82 South American gray foxes (Lycalopex griseus). Dog and fox blood samples were first screened for DNA of Anaplasmataceae followed by two Ehrlichia-specific protocols. Antibodies against Anaplasma sp. and E. canis were assessed by immunofluorescence in dogs. Ectoparasites were collected and identified, with the determination of the lineages of the Rhipicephalus sanguineus species group by molecular and phylogenetic analyses. Finally, potential risk factors for infection were investigated across the different bioclimatic regions and host species. All DNA amplicons obtained from the screening protocol corresponded to Anaplasma platys. The occurrence of both A. platys DNA and antibodies was confirmed in all six bioclimatic regions, except for regions at high altitude and/or without either R. sanguineus species group lineage present. Dogs infested with R. sanguineus ticks were significantly more prone to be infected and exposed to Anaplasma spp. Prevalence of DNA was significantly higher in juvenile (19%) than in adult dogs (9%), whereas the opposite was found for seroprevalence (19% versus 35%, respectively). Overall prevalence of A. platys DNA was higher in dogs (11%) than in foxes (4%), probably owing to markedly lower tick infestations in the foxes. Ehrlichia canis DNA was not detected in any sample, and antibodies against this pathogen were detected only in four dogs, in areas with both R. sanguineus lineages present. Free-ranging dogs in Chile could be favoring the maintenance of A. platys in all areas suitable for its tick vector. Although apparently infrequent, spillovers from dogs to foxes may be taking place and should be considered in management plans in Chile.

Prevalence and Genomic Characterization of Brucella canis Strains Isolated from Kennels, Household, and Stray Dogs in Chile.

Simple SummaryCanine brucellosis caused by Brucella canis is a zoonotic disease that is considered the main infectious cause of infertility and reproductive failure in dogs worldwide, particularly in Latin America. Reports of B. canis infection in people have increased, especially in people who work with dogs and their owners, where the adoption of stray dogs poses a public health risk. Thus, this study determined the prevalence of infection in kennels, household, and stray dogs in the Metropolitan region, Chile, recording the genomic characteristics of the isolated circulating strains. Our results demonstrate that the infection is widespread in the three canine populations analyzed, with no differences in age or sex, and most of the infected animals do not show clinical signs or bacteremia. Furthermore, the high genetic similarity of the isolated strains suggests a common transmission route throughout the country. This study corroborates the need to implement official strategies for the control and prevention of B. canis infection, including sanitary, diagnostic, and educational measures under the One Health vision.Canine brucellosis caused by Brucella canis is a zoonotic disease that causes reproductive alterations in dogs, such as infertility, abortion, and epididymitis. This pathogen is especially prevalent in South America, and due to the lack of official control programs and the growing trend of adopting dogs it constitutes a public health risk that must be addressed. The aim of this study was to determine the prevalence of B. canis infection in kennel, shelter, and household dogs and to characterize the genomic properties of circulating strains, including ure and virB operons and omp25/31 genes. Samples from 771 dogs were obtained, and the infection was detected by blood culture and/or serology in 7.0% of the animals. The complete ure and virB operons and the omp25/31 genes were detected. Interestingly, we found different single-nucleotide polymorphisms (SNPs) in some of the analyzed genes, which could mean a change in the fitness or virulence of these strains. This study provides further evidence about dogs as a source of B. canis strains that can infect people. This also highlights the need to implement official control programs, including the mandatory testing of dogs, especially stray dogs, before adoption.

Babesia vogeli in dogs in Chile.

We report the presence of Babesia vogeli in dogs in Chile. During two surveillance campaigns separated by a year, sixty-three blood samples from free-ranging rural dogs in Coquimbo, Chile, were analysed through conventional PCR screening of the 18S rRNA for Babesia species. Sequencing confirmed the presence of Babesia vogeli in 6.3% of the tested animals, with positive cases in both years. All the sequences showed 100% nucleotide sequence identity among them and99.8% with other previously published sequences from dogs. No clinical signs or haematological abnormalities other than thrombocytopenia were found in the parasitized individuals. This is the first report of a canine piroplasmid in Chile.

First report of molecular detection of Carnivore bocaparvovirus 1 (former CnMV: Canine Minute Virus) in Chilean domestic dogs

ABSTRACT: Carnivore bocaparvovirus 1 (CnMV) infects dogs worldwide and can be responsible for different clinical signs in neonates and bitches during gestation. There is a limited number of CnMV sequences available in the NCBI database, so far. The present preliminary study aimed to obtain evidence of CnMV infection status among domestic dogs in Chile and evaluate the genetic relatedness of the sequences obtained with any type of bocaparvovirus already reported. Two partial nucleotide sequences of the VP2 coding gene were obtained from forty blood samples and compared with 23 available sequences of Carnivore bocaparvovirus from 1 to 6. Chilean sequences grouped within Carnivore bocaparvovirus 1 group, being sequence 5434 (Accession number, MH544475) more similar to the Japanese strain HM-6 and sequence 5423 (Accession number, MH544476) to the Chinese strain SH1.

Métodos de diagnóstico y tratamientos utilizados para la ruptura del ligamento cruzado craneal en perros: encuesta a médicos veterinarios de Chile

The cranial cruciate ligament (CrCL) is an important anatomical structure of the stifle that contributes to joint stability. Tears of the CrCL are frequent orthopaedic lesions in dogs and the diagnosis is based on orthopaedic examination. Despite the large number of surgical methods described, no treatment has been universally accepted in veterinary medicine and the treatment is based on the preferences of the surgeon. With regard to diagnosis and treatment, the aim of the present study was to assess the preferred method in Chile to diagnose and treat the rupture of CrCL in dogs. Out of 307 surveys handed out, 206 questionnaires were obtained and 49 (23%) of them stated that one or more methods were performed to diagnose and treat CrCL rupture in dogs, while twenty one (10, 19%) questionnaires were answered in full. The diagnosis is mainly based on palpation and radiography is the most common complementary method used. Regarding the treatment for the CrCL rupture, the extraarticular surgical technique was the most common method of treatment (90, 47%). In conclusion, we found out that few veterinarians in Chile diagnose and treat CrCL rupture in dogs. The diagnoses for CrCL rupture is mostly performed through palpation of the affected stifle while imaging diagnostic methods are scarcely or not applied. The extraarticular technique is the preferred method to treat CrCL rupture in dogs in Chile.

Bartonella rochalimaeand OtherBartonellaspp. in Fleas, Chile

To the Editor: Fleas are involved in the natural cycle of different Bartonella spp. Among the 20 currently recognized Bartonella spp., 13 species or subspecies have been implicated in human disease. Recently, B. rochalimae was identified in a patient who had received numerous insect bites and subsequently had bacteremia, fever, and splenomegaly after visiting Peru (1). A recent study in Taiwan suggested that rodents could be a reservoir for B. rochalimae (2), but the vector or other mechanism of infection remains unknown. We amplified B. rochalimae, B. clarridgeiae, and B. henselae from fleas (Pulex irritans and Ctenocephalides felis) collected in Chile and discuss the role of these fleas as possible vectors of infection. From 2005 through 2008, we collected 82 fleas from cats and dogs in pounds in Chile: 34 P. irritans, 37 C. felis, and 11 C. canis. Fleas were kept in 70% ethanol and sent to the Special Pathogens Laboratory of the Area de Enfermedades Infecciosas of the Hospital San Pedro, La Rioja, Spain, to be examined for Bartonella spp. Fleas were then rinsed in distilled water and dried on sterile filter paper under a laminar-flow hood. Each flea was crushed with a sterile pestle, and DNA was extracted by lysis with 0.7 M ammonium hydroxide. PCR was used to detect Bartonella DNA (according to the defining criteria for Bartonella spp.); primers targeted the RNA polymerase β-subunit–encoding gene (rpoB) and the citrate synthase gene (gltA) (3–5). PCR primers for a fragment of the 16/23S rRNA intergenic region and the heat-shock protein-encoding gene (groEL) were also used (6,7). Positive controls (B. henselae strain Marseille, kindly supplied by Unite des Rickettsies, Faculte de Medecine, Universite de la Mediterranee, Marseille, France) and negative controls (sterile water instead of template DNA) were used. PCR products were purified, and both strands of each amplicon were subjected to sequence analysis. Nucleotide sequence homologies were searched by using BLAST (www.ncbi.nlm.nih.gov/blast/Blast.cgi). When rpoB primers were used, Bartonella spp. were found in 4 C. felis (4.8%) fleas from cats and in 4 P. irritans (4.8%) fleas from dogs. The same 8 samples were positive when primers for gltA gene and 16/23S rRNA intergenic region were used. Unfortunately, none of the 82 specimens were positive when PCR primers targeting the groEL gene were used. In all experiments, negative controls remained negative. Sequencing of the 825-bp rpoB fragments from the 4 C. felis fleas indicated that they were most closely aligned with the gene sequences of B. clarridgeiae (n = 2, >99% similarity) and B. henselae (n = 2, 100% similarity). Using gltA (380 bp), we found 100% similarity with B. clarridgeiae and B. henselae. Accordingly, the 16/23S rRNA amplicons from these specimens exhibited 100% similarity with the corresponding sequences of B. clarridgeiae (154 bp) and B. henselae (172 bp). Amplicons for the rpoB fragment gene obtained from 4 P. irritans fleas showed highest similarity (97.2%–99.5%) with rpoB of B. rochalimae. Three were identical, and we deposited the consensus sequence in GenBank in 2006 under the name “uncultured Bartonella sp.” and accession no. {type:entrez-nucleotide,attrs:{text:DQ858956,term_id:111378444,term_text:DQ858956}}DQ858956. The sequence differed from those described for all known Bartonella spp. and phylogenetically was most closely related to B. clarridgeiae (8). The sequence of the protein encoded by rpoB in these 3 specimens (protein_id {type:entrez-protein,attrs:{text:ABH09235,term_id:111378445,term_text:ABH09235}}ABH09235) had 3 aa changes (121I→V, 233K→I, and 274N→E) with respect to the deduced sequence of the RpoB protein for B. rochalimae. The importance of these changes remains unknown. The remaining nucleotide sequence was recently submitted to GenBank under accession no. {type:entrez-nucleotide,attrs:{text:FJ147196,term_id:205289911,term_text:FJ147196}}FJ147196, designated B. rochalimae because isolation of this new Bartonella spp. was reported in 2007 (1). These 4 specimens also yielded positive PCR products for gltA (380 bp) and 16/23S rRNA (≈175 bp). Subsequent nucleotide sequence analysis showed 100% homology with the corresponding partial nucleotide sequences from B. rochalimae. In 2002, Parola et al. (9) amplified Bartonella DNA by using PCR with Pulex spp. fleas collected from persons in Peru and suggested the existence of a new Bartonella sp. The nucleotide sequence of the 16S-23S ribosomal RNA intergenic spacer obtained from 1 genotype (clone {type:entrez-nucleotide,attrs:{text:F17688,term_id:4824584,term_text:F17688}}F17688) was nearly identical to the corresponding sequence of B. rochalimae. This finding suggests that Pulex spp. fleas could be vectors. Cat scratch disease has been reported in Chile, and B. henselae has been found in cats in Chile (10). Thus, our finding of B. henselae and B. clarridgeiae in C. felis fleas from Chile confirms the risk for exposure of humans in contact with cat fleas. Furthermore, our finding of B. rochalimae in P. irritans fleas from dogs in Chile supports the possibility that P. irritans fleas could be vectors for B. rochalimae. These findings are of public health importance because they identify possible vectors of these human pathogens.

Anaplasma platysin Dogs, Chile

We conducted a 16S rRNA nested PCR for the genus Ehrlichia and Ehrlichia spp. with blood samples from 30 ill dogs in Chile. Phylogenetic analysis was performed by using groESL gene amplification. We identified Anaplasma platys as 1 of the etiologic agents of canine ehrlichiosis.