PREVALENCE, ANTIMICROBIAL RESISTANCE PROFILES OF CLINICAL AND SUBCLINICAL MASTITIS IN LACTATING COW WITH ASSESSMENT OF TREATMENT TRIAL

Abstract

This work investigated the prevalence of bovine mastitis in a dairy farm, Ismalia governrate, Egypt with phynotypic and genotypic clarification of the causative bacteria and their antimicrobial susceptibility. Also a treatment trial with a combination of Cafalexin, Kanamycin was evaluated. The total prevalence of mastitis was 31.82% (119/374) at cow level and 17.01% (247/1452) at quarter level. 261 isolates were detected. (74.33%) belong to staphylococcus spp and (25.67%) to streptococcus spp. as major microorganisms (CNS (42.53%) s.aurus (31.80%) s. uberis (12.26%), s. agalactia (8.81%) and s. dysagalactia(4.59%). The isolates were tested against 15 antimicrobial agents and the highest percentage of resistant bacteria was for AMC, P, C and E. while the lowest rate was  for CN, CIP, CL and K. Molecular Characterization of isolated pathogens and antimicrobial resistance genes was performed by PCR on 15 isolates. blaTEM-1 Was the most frequently detected gen followed by aadA1, dfrA1, cmlA, sul1, and tetA. 110 infected udder quarters were enrolled for 21 days to evaluate the treatment with Terrexine LC intramammary suspension 10g on six occasions at 12 h intervals and gentamycin intramuscular injection (1cm/20kg Bw for 3-5 days in cows with systemic reaction. A high significant reduction was recorded for the log10 SSC, log10 TBC and the level of LDH in milk after treatment  compared their level before treatment (P-value <0.0001***).  The milk season for cows, degree of mastitis or type of microorganism isolated before treatment have no effect on the recovery rate P-value ˃0.05.  In conclusion, the emergence of multidrug-resistant strains is greatly increased so antibiotic usage must be Restricted.  PCR can help in the rapid detection of the resistant strains.  Treatment of mastitis with combination of antimicrobial may reduce drug resistance. Bovine mastitis still needs updated knowledge on the causative microbes and their antibiotic resistance patterns for optimal control and treatment.