Comparison of bones of 4 strains of laying hens kept in conventional cages and floor pens ,
Bibliographic record
Abstract
The maintenance of bone strength has been an important issue in the debate over cage use for laying hens. Bone strength depends on adequate mechanical load and cages restrict movement. Four laying crosses (Lohmann White, Lohmann Brown, H&N White, and Rhode Island Red × Barred Plymouth Rock cross hens) were housed in conventional cages or in floor pens equipped with perches and nest boxes to measure the effect of the housing system on bone strength. Approximately 15 hens of each genotype from each housing system were killed at 50 wk of age and the radius and tibia of each were removed for analysis. There were no differences between the Lohmann White and H&N White (White Leghorn) hens, likely because of their similar genetic background. The Lohmann Brown and the cross hens (brown-egg layers) were larger and they had heavier bones, but the bone density was not different from that of the other lines. The radius was heavier for hens kept in floor pens than for those kept in cages, but the tibia was not. When hens were kept in floor pens, both bones had greater cortical bone density and cross-sectional area, but the difference between housing systems in cortical bone cross-sectional area was much greater for the radius than it was for the tibia. Although the movement of hens in cages is limited, they spend a great deal of time standing, which puts a mechanical load on the tibia. Hens in floor pens are able to stretch their wings or fly, in contrast to hens kept in cages, which likely explains why the difference between housing systems in cortical bone was greater for the radius than for the tibia.
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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 | 0.002 | 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".