Bacterial Pathogens Involved in Bovine Mastitis and Their Antibiotic Resistance Patterns in the Adamawa Region of Cameroon

Data on the sensitivity pattern of bacteria are scarce in sub-Saharan Africa, especially in Cameroon. This paper reports the prevalence of bovine mastitis and major bacterial pathogens associated with the disease and their antimicrobial profiles in the Adamawa Region of Cameroon. It was conducted to investigate the sensitivity pattern of bacteria isolated from mastitis cases that could be helpful in the application of appropriate therapeutic measures. For this study, 224 lactating cows were examined. A high average prevalence (59.8%) in subclinical mastitis was recorded as compared to clinical mastitis (3.6%; χ2=163.7, P=10-4). Out of the 135 clinical and subclinical mastitis cases recorded, bacteria were cultured from 115 milk samples (85.2%, n=135). In all, 14 different bacterial pathogens were isolated including: coagulase negative Staphylococci (27.5%), Staphylococcus aureus (23.3%), Escherichia coli (11.3%), Streptococcus agalactiae (7.1%), Streptococcus dysagalactiae (4.2%), Enterococcus faecalis (2.8%), Klebsiella pneumoniae (2.8%), Enterobacter aerogenes (2.1%), Pseudomonas aeruginosa (2.1%), Corynebacterium spp. (1.4%), Proteus spp. (1.4%), Brucella spp. (1.4%), Mycoplasma spp. (0.7%), and Mycobacterium spp. (0.7%). A major variationin the sensitivity of isolated bacteria against 14 different antibiotics was noticed. Overall the sensitivity test revealed that Enrofloxacin, Gentamicin, and to a lesser extent Oxacillin and Amoxicillin/Clavulanic acid, were most efficacious. The study gives a significant contribution to the epidemiology and contributes to reducing the lack of knowledge about the antibiotic resistance patterns of major bacterial mastitis in Cameroon. The application of these antibiotics could be beneficial in resolving the cases of bovine mastitis in dairy herds. Keywords: Antibiotic resistance; Cameroon: Cattle; Mastitis; Pathogenic bacteria