Prevalence and antibiotic resistance of bacterial pathogens isolated from dogs/Part I: Skin, urogenital system and milktests

This study is to give a survey of the infectious bacterial agents isolated from dogs and of their antimicrobial susceptibility. The results of routine bacteriologic examinations of a broad variety of clinical samples from dog s during the years 1991 through 1994 at the Institute of Microbiology and I nfectious Diseases, Hannover Veterinary School, Germany, were compiled and evaluated with regard to other studies published. Among the 4692 samples in cluded in this study there were specimens from the skin, the conjunctiva, t he urogenital tract, the respiratory tract, from the bones and joints, the intestinal tract and organs from dead puppies. Staphylococcus (Staph.) intermedius was among the most frequently isolated bacteria. It predominated in samples from the skin (87,4 % of the skin spec imens containing bacteria), the mucous membranes of the body orifices (for example 31,9 % of the vaginal swabs, 45,5 % of the conjunctival swabs) as w ell as in samples from bones and joints (68,6 % and 24,3 % respectively). B eta-hemolytic Streptococci were cultivated from similar sites as Staph. int ermedius though less frequently (16,4 % of the skin samples, 29,1 % of the vaginal samples, 9,0 % of the conjunctival swabs, 4,0 % of the bones and 2, 8 % of the joints). The bacterium most common in urogenital samples was Esc herichia (E.) coli. It was grown from 55,2 % of the urine samples, from 72, 8 % of the uterine swabs and from 56,5 % of the samples obtained from the p rostata. Samples from the respiratory tract often contained Pasteurella mul tocida or other Pasteurella spp. (for example 35,5 % of the tracheal swabs) but also E. coli and alpha- or gamma-hemolytic Streptococci, the significa nce of the latter depending on the circumstances of the particular case of a diseased dog. The evaluation of the 3562 results of sensitivity testings showed that in infections with Staphylococci, Enterococci, Pseudomonas spp. , E. coil and Proteus spp. one has increasingly to be aware of resistances of these bacteria against the routinely used antibiotics. Most staphylococc al strains were resistant to P-lactam antibiotics with exception of oxacill in (resistance rate 3,2 %), cephalexin (resistance rate 6,0 %) and amoxicil lin-clavulanic acid (resistance rate 2,0 %). Many isolates of E. coli prove d to be resistant to broad spectrum antibiotics such as chloramphenicol (34 ,6 %), oxytetracyline (46,5 %) and trimethoprim-sulfamethoxazole (28,2 %). Pseudomonas spp., Enterococci and Proteus spp. were susceptible to hardly a ny of the antibiotics tested.