Streptococcus agalactiae, an important etiological agent of bovine mastitis is poorly studied as a cause of caprine mastitis in India. Thus, the present study aimed at studying the antibiogram and virulence profile of S. agalactiae isolates from cases of caprine subclinical mastitis. In the present study, prevalence of subclinical mastitis in goats was estimated to be 51% by SLS test. Out of a total of 100 milk samples tested, seven S. agalactiae isolates (7%) were obtained and all isolates were obtained from mastitic milk samples. The S. agalactiae isolates were screened for ten virulence genes, of which only six were detected viz., cyl, glnA, cfb, hylB, fnbB and scaA gene. To our knowledge, this is the first report on detection of cyl, glnA, hylB, fnbB and scaA genes in caprine S. agalactiae isolates from India. Out of six antibiotic resistance genes tested, only one gene, i.e. tetM gene was detected by PCR. Antibiotic sensitivity results revealed highest resistance to tetracycline and ampicillin. Moreover, 71.4% of isolates were found to be multidrug-resistant and all MDR isolates exhibited a MAR index more than 0.2 which is reflective of the wide antibiotic usage in goats across Punjab.
Antibiotic Resistance, Caprine Subclinical Mastitis, MALDI-TOF, S. agalactiae, Virulence Genes
© The Author(s) 2025. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License which permits unrestricted use, sharing, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.