RESUMO
Multidrug-resistant bacteria have become the predominant etiology in bovine female reproductive tract infections and thus require effective treatment approaches. The main goal of this study was the molecular detection of mecA, blaZ, tetK, and aacA-aphD genes in Staphylococcus aureus (S. aureus) responsible for methicillin, beta-lactam, tetracycline, and aminoglycoside resistance respectively. Phylogenetic analysis was conducted to check the homology of staphylococcal genes with NCBI sequences. The in-vitro efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) in combination therapies against MDR S. aureus was evaluated using well diffusion assay and checkerboard method. Vaginal swab samples (n = 384) collected from bovines suffering from endometritis, pyometra, and retained placenta were tested for S. aureus. Results showed a 17.96% overall prevalence. Both phenotypic and genotypic resistance was observed among S. aureus isolates with 50.72% and 37.68% isolates being confirmed as methicillin-resistant (MRSA), 36.23% and 18.84% isolates exhibiting beta-lactam, 40.58%, and 27.54% isolates showing tetracycline, and 33.33% and 36.23% isolates showing aminoglycosides resistance based on disc diffusion and gene confirmation, respectively. Phylogenetic analysis indicated homology with previously reported Pakistani isolates suggesting the possibility of MDR S. aureus transmission within and between animals. Synergy testing indicated that combinations of ceftriaxone-ketoprofen (153.77%), ceftriaxone-meloxicam (149.55%), amoxiclav-flunixin meglumine (106.06%), and oxytetracycline-flunixin meglumine (104.47%) showed synergy on well diffusion assay. Based on the fractional inhibitory concentration index by checkerboard method, oxytetracycline-meloxicam and gentamicin-ketoprofen combinations exhibited synergistic interaction. In conclusion, MDR S. aureus resistance was mitigated in-vitro through the combination of antibiotics (oxytetracycline, gentamicin) with NSAIDs (meloxicam, ketoprofen) that could be used to create therapeutic strategies for bovine reproductive issues.
RESUMO
Camel is a multipurpose animal bred to produce milk, meat, and transport and serves as a financial reserve for pastoralists by playing an important role in social prestige and prosperity. Camel milk is a good substitute for human milk because of its exceptional nutritional properties. Udder infections are considered one of the main limitations to camel farming. In recent decades, the disease has been reported by numerous camel-producing countries in Africa and Asia, such as Egypt, Somalia, Sudan, Kenya, Saudi Arabia, and Iraq. The current review provides an overview of the forms of camel mastitis, which can be clinical mastitis characterized by hardening and swelling of the breast, pain on palpation, and visible changes in the colour and texture of the milk or subclinical mastitis refers to the presence of inflammation with no obvious signs and it can be detected by indirect tests such as the California mastitis test (CMT), somatic cell count (SCC), and microbiological examination. Major pathogens of camel mastitis are Staphylococcus aureus, Streptococcus agalactiae, Escherichia coli, and Corynebacterium bovis. Regarding the risk factors for camel mastitis, this study provides an overview of the most important risk factors such as severe tick infestation, teat injuries, hygienic milking protocols, and physiological disorders causing mastitis. The use of indirect tests and bacteriological studies as diagnostic tools and their values for detecting camel mastitis will also be reviewed. Based on the above, further epidemiological studies on camel mastitis are needed to have solid scientific data on disease transmission, pathogen characterization, other possible risk factors or diagnostic methods, and the impact of the disease on public health. Proper control strategies should be adopted through early diagnosis, treatment and by avoiding potential risk factors to get good quality milk from camels.
