An outbreak in week-old broiler chicks caused by a highly virulent and multidrug-resistant strain of <i>Salmonella</i> Gallinarum
Bibliographic record
Abstract
Salmonella Gallinarum is a bacterium that causes significant economic losses in poultry farming and usually infects adult birds. This study aimed to characterize the unusual histological findings and genetic profile of a Salmonella Gallinarum (SG) strain isolated from a natural outbreak that affected 1500 broiler chicks in their first week of life. To confirm the diagnosis, necropsy, histopathology, and immunohistochemistry were performed on 19 chicks, with bacterial isolation in two of them, followed by confirmation through PCR, genetic sequencing, and genomic analysis. The outbreak revealed unusual gross and histological lesions: in the intestines, there was macroscopic haemorrhage of varying severity and, microscopically, the lesions were characterized by histiocytic and heterophilic transmural typhlitis; in the lungs, there was histiocytic interstitial pneumonia of varying intensities. Additional lesions included splenitis, myocarditis, and hepatitis. Salmonella was in situ-labelled in all mentioned organs using immunohistochemistry. Following the virulome and resistome analysis, which compared the genetic profile of the isolate with a reference SG genome, it was found that the isolate from this outbreak contained 36 exclusive virulence genes and six exclusive antimicrobial resistance genes. These genetic alterations may explain the severe systemic lesions observed in these chicks.RESEARCH HIGHLIGHTSSalmonella Gallinarum infection in chicks resulted in a mortality rate of 42%.Chicks had unusual lesions such as haemorrhagic enteritis and interstitial pneumonia.Whole genome analysis of the SG isolate revealed exclusive antimicrobial resistance genes.Higher number of exclusive virulence genes were related to severe fowl typhoid in chicks.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 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) | 0.000 | 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".