Vaginal microbiota of nulliparous and multiparous cows and their resistance to antimicrobials

Infertility and prenatal mortality are the most important causes of production losses in domestic animals. The presence of pathogenic agents in the female reproductive system of cattle can negatively influence the reproductive performance of the herd. The objective of this study was to isolate, quantify, and characterize the components of the vaginal microbiota of multiparous and nulliparous mongrel cows, focusing on proper health and reproductive management. Samples were collected from 20 healthy animals: 10 nulliparous and 10 multiparous cows. The inoculation was performed simultaneously on four different culture media: BBL CHROM agar Candida, BBL Bile Esculin Agar Slants, Baird-Parker Agar, and MacConkey Agar bile salts. The isolated microorganisms were identified according to morphological and biochemical features. Microorganisms were detected in 80% of the nulliparous and 10% of the multiparous cows, with the following frequency: 88.78% of bacteria had morphophysiological characteristics of Staphylococcus spp., 11.22% of Escherichia coli, and 120 isolated yeast colonies which were identified as Candida tropicalis (69%), C. albicans (24%), and C. krusei. Seventeen isolates of Staphylococcus spp. (53.12%) presented sensitivity to all antimicrobials tested: 65.6% to amoxillin, 46.9% to erythromycin, 71.8% to rifampicin, and 46.9% to tetracycline. The rate of resistance to antimicrobials (MDR) was 0.125. The presence of typical microorganisms was detected. The MDR indicated that the isolates did not show multiresistance, with only two (6.25%) resistant to more than one antimicrobial simultaneously. The bacterial isolates studied were sensitive to the antimicrobial drugs tested, demonstrating the potential for use of these active ingredients.