Identification of the skin microbiota of healthy dogs and those with pyoderma

Among the diseases of dogs, pyoderma is a frequent reason for referral to veterinary clinics. To effectively treat pyoderma and develop new strategies for preventing this disease, it is necessary to study the causes of formation and the conditions for the manifestation of pathogenic properties in causative agents. The purpose of the study will be to identify the microbiota isolated from the healthy skin of dogs and those with pyoderma. Washes were collected from the skin of various areas in clinically healthy dogs and dogs with pyoderma. The material was sown on selective media for the isolation of specific genera of microorganisms; after cultivation, pure cultures were identified according to the methods generally accepted in microbiological practice (cultural, tinctorial, morphological, and biochemical tests), according to Bergi's determinant. In addition, the following test systems were used: “STAPHY-test 16”, “En-coccus-test 36”, and “NEFERM test-24”. It was established that coagulase-negative and coagulase-positive species of staphylococci belong to the representatives of the autochthonous microbiota of the skin of clinically healthy dogs, which are isolated from different areas in 100 and 60–68.5 % of cases, respectively—the coagulase-positive species S. pseudintermedius and the coagulase-variable species S. schleiferi subsp. Coagulants occupy up to 65 % of the central niche, and СNS accounts for up to 30 % of all identified staphylococci. The causative agent of pyoderma in monoculture was S. pseudintermedius in 85.8 % of cases. In 57.1 % of cases, association with pyoderma was represented by СPS and Escherichia coli, and microbial association with СPS and Pseudomonas aeruginosa was detected 4.0 times less often – 14.3 % of cases. In 28.6 % of cases, microbial associations included СPS, Proteus in combination with intestinal or Pseudomonas aeruginosa. On the share of coagulase-positive staphylococci S. pseudintermedius, S. aureus, and coagulase-variable subspecies S. schleiferi subsp. Coagulants account for the central part of the staphylococcal microbiota (93.1 %), identified from inflammatory skin foci in pyoderma. At the same time, the species S. pseudintermedius significantly prevailed over other species; in particular, its share accounted for 78.4 % of the staphylococci isolated, which is 16.0 times more than S. aureus and 8.0 times more than S schleiferi subsp. coagulants So, in the etiology and pathogenesis of pyoderma in dogs, a significant role is played by СPS, in particular, the species S. pseudintermedius.