Vol. 10, Special Issue 8s (2021)

Author(s):
D Rani Prameela, M Balumahendiran and A Karthik

Abstract:
Skin infection with abscess formation was observed on thigh regions of equines. Pus swabs from abscess were collected for diagnosis. Pus swabs were inoculated into nutrient broth and then streaked on to the blood agar plates for cultural isolation. Small, dry white colonies were observed after 24hrs of incubation initially. Later creamy white haemolytic colonies with a narrow zone of haemolysis were observed after 72hrs suggestive of Corynebacterium pseudotuberculosis. Further, the isolates were confirmed biochemically showing positivity to catalase, methyl red and urease tests and negative for oxidase, indole, voges proskers and nitrate reduction tests. Direct microscopic examination of cultural smears revealed gram positive pleomorphic rods on grams staining. The antibiotic sensitivity/resistant pattern of the isolates revealed sensitivity to Pencillins, followed by Gentamycin, Kanamycin, Streptomycin and Chloramphenicol and resistance to Tetracylins, Amoxicillin, Ampicillin and Nitrofurans respectively.