Conjunctival cytological examination, bacteriological culture, and antimicrobial resistance profiles of healthy Mediterranean buffaloes (Bubalus bubalis) from Southern Italy

ABSTRACT

Objective: To assess normal conjunctival cytological and bacteriological/fungal flora features in the Mediterranean buffalo (. Bubalus bubalis). Methods: Swabs were taken from the inferior conjunctival sac of both eyes of 57 healthy female buffaloes aged 24-36 months, with no evidence of ocular disease, farmed in Campania region (Southern Italy), for microbiological analysis. Conjunctival eye specimens of both eyes were subsequently obtained by a cyto-brush, for cytological analysis. The antimicrobial susceptibility of bacterial isolates was also determined using the disk-diffusion method on Mueller Hinton agar plates. Results: Cytological examination of conjunctival swab specimens (114 eyes) revealed epithelial cells (basal, intermediate, columnar and superficial) in all samples, whereas neutrophils, lymphocytes and plasma cells were present in 70%, 10% and 2% of samples, respectively. Microorganisms, for a total of 261 aerobic bacteria and 6 fungi, were isolated from 112/114 conjunctival samples [98.25%; 95% confidence interval (. CI) 93.18-99.70]. Only two conjunctival swabs did not yield bacteria and/or fungi (2/114, 1.75%; 95% CI 0.30-6.82). Gram-positive aerobes were most commonly cultured (181/261, 69.35%; 95% CI 63.31-74.81), with Enterococcus faecium and Staphylococcus lentus predominating. Escherichia coli was the most frequently isolated as Gram-negative bacteria (80/261, 30.65%; 95% CI 25.19-36.69). The antimicrobial resistance patterns of the isolated bacteria showed amoxycillin/clavulanic acid and cephalothin as the least sensitive antibiotics for both Gram-positive and Gram-negative bacteria. Conclusions: These results provided first information on normal conjunctival ocular microflora and cytological features in Mediterranean buffalo.