ISOLATION AND IDENTIFICATION OF STAPHYLOCOCCUS SPECIES FROM DOG AND HUMAN

This study aimed to isolate and identify the Staphylococcus species from otitis externa samples of dogs as well as from the tonsillitis, rhino sinusitis and skin lesions of human. The study plan was divided into two parts. The first one including the collection of 100 swabs involved 50 from humans and 50 from dogs from different location in Baghdad governorate during November (2021) to March (2022). Then the sterile swab samples were inoculated on Mannitol salt agar, purified, and identified according to colony morphology, Gram stain, and biochemical tests. The bacterial isolates were confirmed by VITEK technique. The rates of prevalence of staphylococci using the traditional bacteriological methods among the tested samples of dogs and human were showed a significant variation (P0.05) in their values. Significant increases (P0.05) in prevalence of Staphylococci were detected in ear of dogs (60%) and nasal cavity of human (60.6%) when compared to other human samples; 25% in tonsils and 0% in skin. Using the VITEK system, different species of Staphylococcus species were detected in the tested samples of dogs and humans (Table 2). In dog, the predominant species in otitis samples was S. pseudintermedius (43.3%), which followed by S. lentus (16.6%), and S. warneri (13.3%). In human, the predominant species in tonsillitis S. aureus (100%) and the predominant species in rhinosinusitis samples and S. hominis (35%) followed by S. epidermidis (30%). However, no positive samples for different Staphylococcus species were found in skin lesions. The findings of biochemical tests revealed that the isolates of all Staphylococcus species were positives for Gram stain, catalase and high salt containing media; whereas, S. aureus and S. pseudintermedius were the only positive species for coagulase; and the other Staphylococcus species were negatives. This study concluded that the presence of S. pseudintermedius is a fact in infection of areas concluded in this study but in previous studies this bacteria was misdiagnosed with S. aureus that appeared with low number of isolates. Furthermore studies are of great importance to demonstrate the culture and genetic characteristics of different species of Staphylococcus isolated from dogs or other domestic and wild animals.