A high proportion of bacterial isolates from septic neonatal foals in Ontario express multidrug resistance and low susceptibility to first-line antimicrobials
Bibliographic record
Abstract
Objective: To describe common bacterial isolates cultured from sick neonatal foals and their antimicrobial susceptibility and resistance patterns. Methods: Medical records of foals ≤ 30 days of age, admitted to the Ontario Veterinary College from 2020 to 2023, and with a positive aerobic bacterial culture and susceptibility testing performed (Kirby-Bauer method) were included. A descriptive analysis of species isolated and antimicrobial and multidrug resistance profiles was performed. Results: 62 samples from 60 predominantly Thoroughbred (42% [25 of 60]) neonatal foals (median age, 8 days) yielded 104 isolates of 34 bacterial species and genera. Enterococcus spp (22% [23 of 104]), Streptococcus equi subsp zooepidemicus (17% [18 of 104]), Escherichia coli (12% [12 of 104]), Actinobacillus equuli subsp haemolyticus (8% [8 of 104]), and Staphylococcus aureus (8% [8 of 104]) were most frequent. Antimicrobial susceptibility was highest to chloramphenicol (74% [75 of 102]), ceftiofur (68% [71 of 104]), and enrofloxacin (64% [66 of 103]). Gram-positive isolates were most susceptible to chloramphenicol (87% [53 of 61]), ampicillin (75% [38 of 61]), and rifampin (70% [43 of 61]). Gram-negative bacteria were most susceptible to enrofloxacin (81% [34 of 42]) and ceftiofur (71% [30 of 42]). An amikacin plus ampicillin combination had the highest susceptibility (78% [70 of 90]). Multidrug resistance for the 104 isolates was 78% (81 of 104): 66% (41 of 62) for gram-positive isolates and 93% (39 of 42) for gram-negative isolates. Conclusions: S equi subsp zooepidemicus was the most common species and Enterococcus was the most common genus, but a breadth of equine-associated and environmental species were cultured. There was a high proportion of isolates expressing multidrug resistance and low susceptibility to first-line antimicrobials. Clinical Relevance: Ongoing susceptibility monitoring and implementation of an effective antimicrobial stewardship program for this patient population is required.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.003 | 0.006 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".