Identificación de la carga bacteriana en la cavidad oral de Canis lupus familiaris con disbiosis en el refugio Milagrinos, Suba, Bogotá D. C.

Abstract

Canine oral dysbiosis is associated with inflammation and periodontal deterioration; however, information on culturable bacteria in shelter animals remains limited. This study aimed to identify and quantify the culturable bacterial load in the oral cavity of dogs at Milagrinos Shelter in Suba, Bogotá D.C., and assess bacterial diversity, dominance, and antimicrobial susceptibility. Oral swab samples were collected from 30 geriatric dogs with clinical signs consistent with dysbiosis. Procedures included aerobic and anaerobic culture, serial dilutions, colony counts on BHI agar, isolation using enriched and selective media, Gram staining, and biochemical identification using VITEK 2 Compact. Selected isolates underwent agar diffusion susceptibility testing, and ecological indices were calculated using Python. Eight aerobic and two anaerobic morphotypes were identified, the latter corresponding to Veillonella sp. and Fusobacterium necrophorum. Staphylococcus accounted for 53.3% of aerobic recoveries. The Shannon–Wiener (1.997), complementary Simpson (0.853), and Pielou (0.960) indices indicated diversity and high evenness among aerobic morphotypes. Estimates from quantifiable cultures ranged from 20,000 to 1,740,000 CFU/mL. Antimicrobial susceptibility tests showed susceptibility to amoxicillin/clavulanic acid and ampicillin/sulbactam, with variable responses to the remaining antibiotics. In conclusion, the culturable fraction comprised a heterogeneous polymicrobial community. Its characterization provides a basis for the microbiological management of oral health and highlights the importance of using susceptibility testing to guide antimicrobial use.