Vol. 10, Issue 10, Part C (2025)

Author(s): K Jayalakshmi, N Babu Prasath, M Saravanan, R Lakshmi, PK Ramkumar, K Vijayakaran, DVishnugurubaran and A Vijayarajan

Abstract: A study was carried out to identify the etiology of gangrenous mastitis in dairy cattle. A total of 615 cattle was presented with mastitis during January 2024 to March 2025. Out of 615 cattle, 19 dairy cows showed the gangrenous changes like reddish or blackish discolouration of affected quarter with brown coloured haemolytic secretion, anorexia and recumbency. The milk samples were collected from gangrene affected quarters; the bacterial culture was sequentially performed in nutrient agar, mannitol salt agar and MacConkey agar. In bacterial culture, Staphylococcus spp, Klebsiella spp, E. coli, Pseudomonas spp and Bacillus spp were identified based on colony morphology. These bacterial isolates were confirmed with PCR. In PCR, out of 19 isolates, 4, 2, 1 4, 3, 3 and 2 samples were positive for Staphylococcus sciuri, Staphylococcus aureus, mixed infection of Staphylococcus sciuri and Staphylococcus aureus, Bacillus cereus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, respectively. The S. sciuri and B. cereus were predominantly identified in gangrenous mastitis followed by E. coli and K. Pneumoniae. In Klebsiella pneumoniae infection, the gangrenous changes were observed 3 days after infection. The animals were treated with Inj. Ceftiofur sodium @ 2.2 mg/Kg IM along with supportive therapy for 7 days. The prognosis in gangrenous mastitis depends on extend of severe kidney damage. The severe kidney damage was observed in Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa infection compared to Staphylococcus aureus and Staphylococcus sciuri and Bacillus cereus. The prognosis is fair to good with respect to liveability of animals especially infected with Staphylococcus aureus, Staphylococcus sciuri and Bacillus cereus.

DOI: 10.22271/veterinary.2025.v10.i10c.2628