Isolation and identification of Acinetobacter spp. from healthy canine skin

Background: Acinetobacter species can exhibit widespread resistance to antimicrobial agents. They are already recognized as important nosocomial pathogens of humans, but are becoming increasingly recognized in opportunistic infections of animals. Hypothesis/objectives: This study aimed to determine whether Acinetobacter spp. are carried on skin of healthy dogs and, if present, to identify the species. Animals: Forty dogs were sampled at veterinary practices and rescue centres. They were free from skin disease and receiving no systemic or topical treatments. Methods: Skin swab samples were collected from four sites on each dog and cultured. Acinetobacter spp. isolates were detected by biochemical tests and gas chromatography. The species was determined by sequencing the RNA polymerase β-subunit (rpoB) gene. Isolates were screened for OXA carbapenemase genes and class 1 integrons capable of carrying resistance genes, and subjected to antimicrobial susceptibility tests. Results: For 25% dogs sampled (10 of 40), Acinetobacter spp. were isolated at one or more skin sites. Thirteen Acinetobacter spp. isolates were recovered from 160 samples. The most frequently cultured was A. lwoffii (seven of 13), followed by A. baumannii (two of 13), A. junii (one of 13), A. calcoaceticus (one of 13), A. pittii (one of 13) and a novel Acinetobacter species (one of 13). Class 1 integrons and bla_{OXA -23-like} were not detected. Isolates were susceptible to most antibiotics. Conclusions and clinical importance: The study confirms that Acinetobacter spp. can survive on canine skin, where they may be potential reservoirs for infection. This highlights the importance of good hygiene in veterinary practice, adhering to aseptic principles in surgery, and treatment based on culture and susceptibility testing where possible.