Judgment bias, fear, and stress responses of Red Junglefowl and Athens Canadian Random Bred chickens
Bibliographic record
Abstract
Understanding how poultry perceive and interpret their environment is essential to enhancing their welfare. Animal welfare science relies on measures of the behavioral and physiological components of affective states (positive and negative) as welfare indicators. There has been growing interest in using the judgment bias test (JBT) to study birds’ affective states by assessing their responses to ambiguous cues. The objective of this study was to investigate the affective state of two chicken breeds with different evolutionary histories: the Red Junglefowl (RJF), the primary ancestor of modern chickens, and the Athens Canadian Random Bred (ACRB), a rustic domesticated breed, using the JBT at two ages. Another objective was to explore the effect of the JBT on the fear and stress responses of the chickens that participated in the JBT compared to those that did not (NJBT) on days (D) 35 and 63. Fear was evaluated using the tonic immobility test, and stress was measured noninvasively from thermal images of the eye and beak. Chickens successfully discriminated between positive (POS) and neutral (NEU) JBT cues, showing shorter latencies to approach the POS cue (P < 0.0001). While there were no breed differences on D29 of the JBT, RJF chickens exhibited shorter latencies to approach cues than ACRB on D60 (P < 0.001). Independent of testing at both ages, RJF had a longer duration of tonic immobility than ACRB (P < 0.01), indicating higher fearfulness. While the JBT did not affect D35 tonic immobility, JBT chickens had longer tonic immobility durations than NJBT on D63 (P < 0.05). Chickens that participated in the JBT had lower eye and beak minimum surface temperatures than NJBT (P < 0.05), indicating that the JBT may have increased stress post-testing. These findings highlight the influence of domestication on the affective states and the importance of considering fear and stress in measuring the affective states of chickens.
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 | 0.001 |
| 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 | 0.000 |
| 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".