Decreased antibiotic susceptibility and enhanced probiotic production potential of goat milk fermented curd in comparison with cow and buffalo milk

The present study was carried out to characterize and compare the production potential and antibiotic susceptibility of probiotics isolated from goat, cow and buffalo milk. The probiotics isolated from milk fermented curd were compared with regard to their number, morphology, gram staining, motility, bile salt tolerance, pH-resistance, catalase activity, oxidase production and antibiotic resistance. We demonstrated that the probiotics isolated from milk fermented curd of all three species were gram positive, motile, catalase negative, and oxidase negative and were able to produce lactic acid. Further, we observed that buffalo milk is more potent in forming curd with the highest count of probiotics per ml (3.53 × 10!5) as compared to cow (5.8 × 10!6) and goat milk (7×10!7); moreover, goat milk bacterial isolates were more tolerant to acidic pH but were less bile-salt tolerant than cow milk. Also, probiotics isolated from goat milk curd were more resistant to antibiotics (resistant to 12 out of 15 screened antibiotics) than those from cow and buffalo milk (resistant to 8-9 antibiotics). This report shows that goat milk fermented products possess the highest antibacterial potential and are highly acid-tolerant.