Respiratory Pathogens in Québec Dairy Calves and Their Relationship with Clinical Status, Lung Consolidation, and Average Daily Gain
Bibliographic record
Abstract
BACKGROUND: Bovine respiratory disease (BRD) is 1 of the 2 most important causes of morbidity and mortality in dairy calves. Surprisingly, field data are scant concerning the prevalence of respiratory pathogens involved in BRD in preweaned dairy calves, especially in small herds. OBJECTIVES: To identify the main respiratory pathogens isolated from calves in Québec dairy herds with a high incidence of BRD, and to determine if there is an association between the presence of these pathogens and clinical signs of pneumonia, lung consolidation, or average daily gain. ANIMALS: Cross-sectional study using a convenience sample of 95 preweaned dairy calves from 11 dairy herds. METHODS: At enrollment, calves were weighed, clinically examined, swabbed (nasal and nasopharyngeal), and lung ultrasonography was performed. One month later, all calves were reweighed. RESULTS: Twenty-two calves had clinical BRD and 49 had ultrasonographic evidence of lung consolidation. Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni were isolated in 54, 17, and 12 calves, respectively. Mycoplasma bovis was identified by PCR testing or culture in 19 calves, and 78 calves were found to be positive for Mycoplasma spp. Bovine coronavirus was detected in 38 calves and bovine respiratory syncytial virus in 1. Only the presence of M. bovis was associated with higher odds of clinical signs, lung consolidation, and lower average daily gain. CONCLUSIONS AND CLINICAL IMPORTANCE: Results suggested that nasopharyngeal carriage of M. bovis was detrimental to health and growth of dairy calves in small herds with a high incidence of BRD.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| 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".