Pathogenicity and cross protection of infectious bronchitis virus field isolates of Ontario
Bibliographic record
Abstract
Avian infectious bronchitis is an economically important viral disease of poultry resulting in reduced performance, reduced egg quality and quantity, significantly increased susceptibility to concurrent infections and a costly vaccination program. The disease is caused by infectious bronchitis virus (IBV) which is in the family 'Coronaviridae'. IBV is highly infectious and spreads rapidly through horizontal transmission by aerosol or ingestion. In an earlier study sentinel chickens were employed to determine the incidence of IBV in Ontario layers. IBV isolates recovered from the sentinel birds were not vaccine related as shown by genetic analysis of the S1 region. Five of these IBV field isolates were selected for further characterization. Analysis of tracheal lesion scores for each isolate revealed statistically significant differences (p<0.01) between infected groups and negative control group. Moreover, statistically significant differences (p<0.01) were also observed among; particular isolates. Birds exposed to IBV-ON1 and IBV-ON2 had 2.6 and 2.2 grams, respectively, lower average daily weight gains than birds in the negative control group (p<0.01) during the first 11 days of the trial, but not over the entire study period. The protection provided by a commonly used vaccine, MILDVAC-Ma5, was studied by challenging immunized chickens with the respiratory (IBV-ON1) and nephropathogenic (IBV-ON4) viruses. The mean vaccine efficacy for IBV-ON1 was 66.7% indicating that a Massachusetts serotype vaccine would provide some protection against IBV field isolates. (Abstract shortened by UMI.)
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 | 0.000 | 0.000 |
| 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 | 0.000 |
| 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".