Susceptibility to antibiotics of bacterial microorganisms most commonly isolated from clinical and subclinical forms of mastitis in cows

Mastitis is an increasing problem in dairy farms and in the dairy industry. The paper presents changes in susceptibility of strains of bacteria isolated from quarter milk cows from mastitis in 2011, 2012, 2013, 2014, 2015 in the Factory Laboratory of Dairy Cooperative in south-eastern Poland. In total, 3409 strains of staphylococci, 2774 strains of streptococci and 423 strains of E. coli were isolated in these years. Susceptibility to antibiotics was examined by the disc diffusion method on Mueller-Hinton base. On the basis of the research it can be concluded that the highest sensitivity of staphylococci in all study periods is found for cefguin (from 91.2% to 96.1%) and cefapirin (92.2% to 96.2%), and the smallest for tetracycline (18 %), streptomycin (11.9%) and amoxicillin (9.3%). The highest sensitivity of bacteria from the Streptococcus family are cefapirin (97%), cefquinome (96.1%), amoxycycline (95.6%) and cefalexin (89.9%) on average in all years of research. The highest resistance was found for neomycin and streptomycin. They show that during the period under study over 90% of Escherichia coli were sensitive to streptomycin. Sensitivity at the level of 70%-80% was noted for amoxicillin, neomycin and cefapirin. The highest resistance of E. coli bacilli evolved for cefallaxin and tetracycline. Accordingly, early diagnosis of a pathogenic pathogen, and then selecting the appropriate form of treatment, gives you the opportunity to minimize the loss of mastitis in dairy cows.