Caprine Subclinical Mastitis: Prevalence and Etiological Study in Central Iran

Document Type : Original Article

Authors

Department of Veterinary Medicine, Faculty of Veterinary and Agriculture, Shabestar branch, Islamic Azad University, Shabestar, Iran

10.22103/VCBR.2026.25632.1083

Abstract

Subclinical mastitis is a significant problem in dairy goat husbandry and has a negative impact on milk production and animal health. This study investigated the microbial pathogens associated with subclinical mastitis in goats from Isfahan province, focusing on the identification of bacterial species, evaluation of their biofilm-forming ability, and assessment of their antibiotic resistance patterns. A total of 200 goats were randomly selected from three livestock-rich districts in Isfahan. Samples were collected from apparently healthy goats, and the Somatic Cell Count (SCC) was measured to assess udder health. Polymerase Chain Reaction (PCR) was used to detect pathogenic bacteria, including Staphylococcus spp., Staphylococcus aureus, Escherichia coli, and Streptococcus spp. The results showed that 97% of the samples had an SCC value of less than 600,000 cells/mL. Of the 54 samples tested by PCR, 42.59% contained Staphylococcus genes, 25.92% contained S. aureus, and 14.81% contained both Streptococcus spp. and E. coli. In addition, 62.96% of the isolates formed moderate biofilms, while 22.22% exhibited strong biofilm formation. Alarmingly, all isolates showed resistance to amoxicillin, ciprofloxacin, and ceftriaxone. These results underline the need for improved hygiene practices on dairy farms and continuous monitoring of milk quality to effectively address the challenges posed by pathogenic bacteria and antibiotic resistance. In addition, the development of alternative therapeutic methods to treat resistant infections is also recommended.

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Main Subjects

References

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Veterinary and Comparative Biomedical Research
Volume 3, Issue 1
March 2026
Pages 20-28

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