Do flickering LED lights reduce productivity of layer pullets and hens?
Bibliographic record
Abstract
Most characteristics of artificial light sources are well studied, however light-flicker frequency (F) has been overlooked. The purpose of this study was to determine the effect of F on performance of Lohmann LSL-Lite (LW) pullets and Lohmann Brown-Lite (LB) pullets. In addition, pullets were followed through to the laying phase to evaluate long-term effects of F during rearing on productivity. Two trials were conducted with 3 F (30, 90, or 250 Hz) treatments. LW and LB pullets (n = 2,688 per strain [S]) were randomly assigned to floor pens within 8 light-tight rooms (15 pen replicates per F × S for 30 and 250 Hz; 18 pen replicates per F × S for 90 Hz). At 16 wk, pullets were transferred to conventional layer cages, with no flicker treatment applied. Pullet data collected included BW, feed disappearance, flock uniformity, and overall mortality. Hen data collected included BW, feed intake (feed efficiency calculated), mortality, egg production, and egg quality. Data were analyzed using Proc Mixed (SAS 9.4) and differences were considered significant when P ≤ 0.05. Frequency did not affect pullet uniformity or feed disappearance (0-8 wk and 0-16 wk). Pullets reared under 30 Hz had higher mortality (caused by "other") than those reared under 250 Hz. Lohmann Brown-Lite pullets reared under 30 Hz had the highest feed disappearance. Overall mortality was higher for LW pullets reared under 30 Hz compared to LB reared under 30 Hz or 250 Hz. Lohmann Brown-Lite hens reared under 30 Hz were heavier at the beginning of the hen phase (17 wk), however differences related to F were not seen at 40 or 48 wk. Hen day production (%) was higher for hens reared under 30 compared to 90 Hz (P = 0.03), however no other egg parameters were affected by F. Hen feed efficiency and mortality were unaffected by F. These results indicate minor effects of F, during either the pullet or hen phases. The data also suggest that S (LW vs. LB) may affect response to F.
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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 | 0.000 | 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".