Drug resistance in isolated bacteria from milk of sheep and goats with subclinical mastitis in shahrekord district

Four-hundred milk samples from half udders of 20 flocks of native breed goats were aseptically collected. The samples were examined by California mastitis test [CMT]. Twenty-one [5.25%] of 400 were CMT-positive. The CMT-positive samples were then cultured and the following bacteria were isolated: Staphylococcus aureus in 3 [14.28%], CNS [coagulase-negative staphylococci] in 14 [66.66%], streptococci in 4 [19.04%] and Mycoplasma spp. in 11 [52.38%] samples. The isolated staphylococci were examined to evaluate their resistance to different antibiotics by disc diffusion method. CNS resistance to amikacin was 78.5%, to penicillin was 50%, to tetracycline 50%, to ampicillin 42.8%, and to doxycycline was 28.5%. Four-hundred native breed sheep milk samples were taken from 19 flocks in the same conditions. The samples were examined by CMT test. 19 [4.75%] of 400 were CMT-positive. The CMT-positive samples were cultured and the following bacteria were isolated: S, aureus in 2 [10.5%], CNS in 7 [36.8%], streptococci in 2 [10.5%], Pasteurella in 1 [5.26%] and Mycoplasma in 9 [47.37%] samples. The isolated staphylococci were examined for antibiotic susceptibility. CNS resistance to amikacin was 42.8%, and to tetracycline, ampicillin, oxycycline and penicillin was 14.3%. Both isolates of S. aureus were resistance to penicillin

Isolation and antibiotic resistance patterns of Escherichia coli and coagulase positive Staphylococcus aureus from honey bees digestive tract

In this study antibiotic resistance pattern of E. coli and coagulase positive Staphylococcus aureus isolated from honey bees digestive tract of Shahrekord apiaries were studied. From 45 isolated E. coli strains 35 isolates [77.77%] were resistant to one or more antibiotics. The most resistant patterns were to Erythromycin [77.77%], followed by 14 isolates to Nitrofurantoin [31.11%]. From 22 isolations of S. aureus resistance to Penicillin and Erythromycin were 18 [85.71%] and 11 [50.00%] isolates, respectively. Number of isolations in two seasons [fall and spring] was statistically significant [P<0.005], but profile of the antibiotic resistance of the two bacteria in two seasons are not statistically significant