Antimicrobial susceptibility profile of klebsiella species associated with mastitis in cattle from Ssembabule District, Uganda

Abstract

Mastitis is one of the major burdens affecting the dairy sector lowering both the quality and quantity of milk. In an attempt to manage or prevent mastitis, farmers have resorted to frequent and irrational use of antimicrobial drugs that have resulted in the development of resistance to some of the frequently used antimicrobials. This study aimed to establish the prevalence of Klebsiella spp. in mastitis cases and the antimicrobial susceptibility profile of the isolates. A total of 224 lactating cows in selected herds were examined for both clinical and subclinical mastitis. Screening for subclinical mastitis was done using the California Mastitis Test (CMT) while that of clinical mastitis was through clinical examination. Milk from CMT positive cases were taken to the laboratory for bacteriological analysis. Klebsiella spp. were isolated and then identified by morphological and biochemical tests. The antimicrobial susceptibility patterns of Klebsiella isolates were determined using Kirby-Bauer disc diffusion method. The prevalence of subclinical mastitis in the 224 cows screened was 47.39% and that of Klebsiella spp. was 39.1%. Almost all the Klebsiella isolates (95.56%) were resistant to Erythromycin, while most of the isolates (84.44%) were sensitive to Gentamycin. The isolates exhibited variable susceptibility to Ceftriaxone, Cotrimoxazole, Meropenem, Tetracycline, Ceftazidime, Cefepime and imipenem; and over four isolates demonstrated multiple drug resistance. Among Gram-negative bacteria, Klebsiella spp. potentially causes bovine mastitis and exhibited resistance to some of the commonly used antimicrobials in livestock and dairy production systems. There was high prevalence of Klebsiella spp. isolated from milk samples of bovine mastitis cases, with highest resistance demonstrated against antimicrobial classes of Macrolide followed by third generation Cephalosporin and then Tetracyclines. Highest susceptibility was exhibited for aminoglycoside followed by carbapenems. Farmers are encouraged to regularly screen their lactating cows for mastitis so that the infected are given early treatment. Then veterinary practitioners are required to conduct antimicrobial susceptibility testing to guide the choice of drug for appropriate treatment.