Prévalence et antibiorésistance des entérobactéries isolées des mammites chez la vache laitière dans la région d’Ain Témouchent

Abstract

Bovine mastitis is an inflammation of the mammary gland, generally caused by a bacterial infection, which affects the health of dairy cows and has a significant economic impact due to reduced milk production and altered milk composition. This study aimed to evaluate the prevalence and antibiotic resistance of enterobacteria isolated from dairy cows in the Ain Témouchent region, as well as to characterize the antibiotic resistance profiles of isolated bacteria, particularly Escherichia coli and Klebsiella pneumoniae. During this study, 162 lactating cows were screened for subclinical mastitis using the California Mastitis Test (CMT). Milk samples with a positive CMT result then underwent bacteriological analysis. The results highlighted that mastitis remains a major pathology in cattle farms in Algeria, with a prevalence of 29.01% in the Ain Témouchent region. Bacteriological analyses of samples from subclinical mastitis generally showed a predominance of E. coli with a frequency of 19.13%, followed by K.pneumoniae with an isolation frequency of 6.01%.The in vitro sensitivity study of the identified bacteria to antibiotics revealed good sensitivity of E. coli to cefotaxime, chloramphenicol, kanamycin, nalidixic acid, trimethoprim+sulfamethoxazole, and colistin sulfate. For K.pneumoniae, good sensitivity was observed for amoxicillin+clavulanic acid, cefotaxime, nalidixic acid, ofloxacin, and trimethoprim+sulfamethoxazole. Regarding the resistance level, very high resistance was observed for E. coli to amoxicillin+clavulanic acid, ampicillin, amoxicillin, tetracycline, and ofloxacin. For K.pneumoniae, very high resistance was noted for ampicillin, amoxicillin, and tetracycline. These results pave the way for more in-depth studies on certain functions that could be targets for infection control strategies.