Antibiotic-resistance, enterotoxin gene profiles and farm-level prevalence of Staphylococcus aureus in cow, sheep and goat bulk tank milk in Jordan

Bulk tank milk was collected from 44 cow, 47 sheep and 26 goat farms to determine antibiotic resistance, enterotoxin gene profiles, and Staphyococcus aureus prevalence in Jordan. S. aureus (n = 169) was detected in 69.2% farms; 65.9% cow, 68.1% sheep, and 76.9% goat farms. Thirty-three (19.5%) isolates harboured enterotoxin genes, sec was the most prevalent (75.8%) and six profiles were observed. Resistance to ≥1 antibiotic class and multidrug resistance were exhibited by 93.5% and 59.2% of the isolates, respectively. One goat and two sheep isolates resisted seven antibiotic classes. More than 50% of the isolates resisted penicillin, ampicillin, and clindamycin and 30-40% resisted tetracycline, gentamicin, rifampin and erythromycin. About 20% resisted cefotaxime, doxycycline and amoxicillin-clavulanic acid. Meanwhile, 10% resisted chloramphenicol, sulfamethoxazole-trimethoprim and ciprofloxacin. The resistance found is alarmingly higher than that elsewhere and necessitates programs to promote judicious use of antibiotics in Jordan.