Udder pathogens and their resistance to antimicrobial agents in dairy XXXX in Estonia.

@entity5967 @entity114 @entity794 @entity3639 @entity281 @entity8211 @entity869 @entity803 @entity291 @entity1271 @entity526
BACKGROUND: The goal of this study was to estimate the distribution of udder pathogens and their antibiotic resistance in Estonia during the years 2007-2009. METHODS: The bacteriological findings reported in this study originate from quarter milk samples collected from @entity291 on Estonian dairy farms that had clinical or subclinical @entity1271 . The samples were submitted by local veterinarians to the Estonian Veterinary and Food Laboratory during 2007-2009. Milk samples were examined by conventional bacteriology. In vitro antimicrobial susceptibility testing was performed with the disc diffusion test. Logistic regression with a random herd effect to control for clustering was used for statistical analysis. RESULTS: During the study period, 3058 clinical @entity1271 samples from 190 farms and 5146 subclinical @entity1271 samples from 274 farms were investigated. Positive results were found in 57% of the samples (4680 out of 8204), and the proportion did not differ according to year (p > 0.05). The proportion of bacteriologically negative samples was 22.3% and that of mixed growth was 20.6%. @entity8211 . uberis) was the bacterium isolated most frequently (18.4%) from cases of clinical @entity1271 , followed by @entity526 (E. coli) (15.9%) and @entity5967 . agalactiae) (11.9%). The bacteria that caused subclinical @entity1271 were mainly @entity794 ( @entity794 ) (20%) and coagulase-negative staphylococci (CNS) (15.4%). The probability of isolating @entity794 from milk samples was significantly higher on farms that had fewer than 30 @entity291 , when compared with farms that had more than 100 @entity291 (p < 0.005). A significantly higher risk of Str. agalactiae @entity281 was found on farms with more than 600 @entity291 (p = 0.034) compared with smaller farms. The proportion of @entity794 and CNS isolates that were resistant to @entity114 was 61.4% and 38.5%, respectively. Among the @entity526 isolates, @entity869 , @entity3639 and @entity803 resistance were observed in 24.3%, 15.6% and 13.5%, respectively. CONCLUSIONS: This study showed that the main pathogens associated with clinical @entity1271 were Str. uberis and @entity526 . Subclinical @entity1271 was caused mainly by @entity794 and CNS. The number of @entity794 and Str. agalactiae isolates depended on herd size. Antimicrobial resistance was highly prevalent, especially @entity114 resistance in @entity794 and CNS.
