Assessment of antibiotic resistance in fecal samples from calves with diarrhea in the Cajamarca region, Peru

Diarrhea is associated with infectious bacteria that cause mortality in calves, such as Escherichia coli, representing a problem for milk and meat producers globally, causing large economic losses. This study assessed the resistance to E. coli strains isolated from diarrheal feces of newborn calves from the Cajamarca region. Fifty two (52) fecal samples from calves from five provinces of the Cajamarca region were collected for the isolation of E. coli on MacConkey agar with sorbitol. The molecular identification of E. coli was performed by amplification of the uidA gene by conventional PCR and then antibiotic susceptibility/resistance was assessed using the Kirby-Bauer methodology and antibiotic discs with neomycin, tetracycline, sulfamethoxazole-trimethoprim and enrofloxacin. The results were that 96.15 % of E. coli strains were resistant to tetracycline, 51.92 % to sulfamethoprim, 26.92 % to neomycin and 9.61 % to enrofloxacin. It was also demonstrated that 30.76 % had resistance to two drugs, 19.23 % to three drugs and 5.76 % to four drugs; a significant difference was found in resistance to tetracycline (P<0.0001). It is concluded that newborn calves from the Cajamarca region that presented diarrhea are carriers of antibiotic-resistant E. coli, representing a problem for cattle farmers, since these strains can cause the death of animals and contribute to the spread of antibiotic resistance.