Isolation and molecular profiling of tetracycline-resistant Staphylococcus aureusisolates from cases of gangrenous dermatitis in poultry

Gangrenous dermatitis (GD) is a major disease of the poultry industry responsible for causing significant economic losses. A plethora of microorganisms are responsible for causing gangrenous dermatitis in poultry, with the major causative agents being Clostridium septicum, Clostridium perfringens type A, as well as aerobic bacteria such as Staphylococcus aureus. The current study aimed to molecularly characterize Staph. aureus in sporadic outbreaks of gangrenous dermatitis in poultry farms of Nagpur. A total of 05 samples suspected of gangrenous dermatitis were collected and subjected to conventional and further molecular methods to detect tetK-resistant S. aureus isolates. The study revealed the presence of Staphylococcus aureus in 03(60%) samples by PCR amplifying nuc gene. Antibiotic susceptibility assay revealed that 02(66.66%) isolates were resistant to Tetracycline, 01 (33.33%) to Gentamicin, Ceftriaxone, Cefotaxime, Amikacin, Cefaclor, Amoxicillin-Sulbactam, and Chloramphenicol, respectively. Moreover, out of these phenotypic tetracycline-resistant S. aureus isolates, only 01 isolate was ascertained positive by PCR amplifying the tetK gene. This study implies that more research is needed concerning the role of S. aureus in causing gangrenous dermatitis in poultry, as well as the detection of antibiotic-resistant strains of S. aureus to develop better strategies for controlling future outbreaks.