Hatching egg characteristics, chick quality, and broiler performance at 2 breeder flock ages and from 3 egg weights
Bibliographic record
Abstract
The objective of this study was to determine the effects of flock age and egg weight on hatching egg characteristics, fertility, hatchability, salable chick production, and broiler performance using a commercial Cobb 500 broiler breeder flock. Hatching eggs from the same breeder flock in 3 weight categories (light, average, and heavy) were obtained from a commercial hatchery when the birds were 29 and 59 wk of age. One group of eggs per age and weight category was selected to assess specific gravity and was broken open to weigh egg components. Another group of eggs was incubated for 21.5 d and incubation parameters were measured. At hatching, all salable chicks were individually weighed and placed in floor pens, where they were grown out for 41 d. Daily mortality, weekly feed consumption, and individual BW at 21 and 41 d were recorded. Irrespective of flock age and egg weight, all eggs had a specific gravity lower than 1.080, the commercial set value. Eggs from the young flock age had a smaller proportion of yolk and a greater proportion of albumen. Age affected fertility, with a lower value observed at 29 wk of age. Chicks from the flock at 59 wk hatched earlier than chicks from the flock at 29 wk, and light eggs hatched earlier than both average and heavy eggs. Broilers from the 29-wk-old breeders had a lower final BW than broilers from the 59-wk-old breeders. The smaller proportion of yolk in eggs from 29-wk-old broiler breeders may be associated with the low final BW observed in their offspring. This could mean that chicks hatching from young broiler breeders, which produce eggs with small yolks, may be at a disadvantage when reared under the same conditions as chicks produced by older broiler breeders whose eggs have larger yolks.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 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".