DIAGNOSTIC STRATEGIES AND STRAIN TYPING FOR JOHNE'S DISEASE IN WOOD BISON (BISON BISON ATHABASCAE)
Bibliographic record
Abstract
Cattle diseases are considered a major threat to wood bison (Bison bison athabascae) conservation. Johne's disease (JD) is a chronic infectious enteritis caused by Mycobacterium avium subspecies paratuberculosis (Map), that affects domestic and wild ruminants globally and could negatively impact wood bison health. Clinical manifestation of JD in free-ranging or captive wood bison has not been documented. We studied animals in a captive wood bison herd in Alberta, Canada 1) to detect Map in bison clinically suspected of Johne's disease, by histopathology, quantitative PCR (qPCR), and isolation by culture; 2) to identify optimal tissue samples for Map detection; and 3) to identify the strain(s) of Map isolated. Six wood bison were evaluated with clinical signs suggestive of JD. We performed necropsies within 24-48 h after euthanasia and collected 24 tissue samples from each bison. At necropsy, no evidence of thickening or corrugation of the intestinal mucosa was observed in any bison. On histopathologic examination, granulomatous lesions with acid-fast bacilli were more frequent in the paracortex of the midjejunal lymph node (LN) and distal jejunal LN, followed by ileal LN, in comparison to the rest of the tissue samples evaluated. In general, tissue culture had the highest proportion of positive samples, with 62.5% (90/144) of positive samples, followed by F57/IS900 qPCR with 43.1% (56/130), and histopathology with 29.0% (38/131). We concluded that distal jejunum and its associated lymph nodes were the most reliable tissue samples for detecting Map, regardless of tissue autolysis or the absence of visible gross lesions. Finally, using IS1311 PCR-restriction enzyme analysis and single-nucleotide polymorphisms, we identified a type II (cattle) strain, secondary clade, in tissue samples. These findings have practical relevance for field necropsies as they provide evidence to direct selection of preferred sampling sites to detect Map in wood bison and to choose appropriate diagnostic techniques.
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 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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| 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 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".