Seroprevalence of Lawsonia intracellularis in Ontario swine herds
Bibliographic record
Abstract
Objective: To estimate the seroprevalence of Lawsonia intracellularis in finisher pigs and sows in the province of Ontario. Methods: Serum samples from a total of 1061 pigs in 37 Ontario commercial herds were collected and tested using the indirect immunofluorescent antibody test. Differences in within-herd prevalence for type of herd, continuous flow or all-in, all-out management in the finishing barn, and inclusion of in-feed antibiotics were examined. Results: Seroprevalence of L intracellularis was 90% for sows and 56% for finisher pigs. Seventy-three percent of herds were seropositive. Within-herd prevalence was higher in farrow-to-finish farms than in multi-site operations (P < .001), and lower in herds with all-in, all-out rather than continuous-flow management in the finishing barn (P < .01). Implications: Under the conditions of this study, seroprevalence of L intracellularis was high, suggesting that the organism is widespread in the Ontario swine population. More sows than finisher pigs are seropositive. Serologic tests are valuable tools for determining the status of the herd with respect to L intracellularis infection.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".