Assessing greenhouse gas and ammonia emissions: A comparison of three egg production systems in Québec, Canada
Bibliographic record
Abstract
In Quebec, the phase-out of the conventional cage (CC) system for egg production, is expected to be completed by 2036, with a transition to alternative systems such as enriched colonies (ECs) and cage-free (CF) housing. This study aimed to assess Greenhouse gas (GHG), and ammoniac (NH3) emissions associated with those systems. The investigation involved one visit per farm to 30 commercial laying hen facilities in Southern Québec, Canada. The findings revealed that the CF system exhibited the highest numerical average of CO2 emissions (3207 ± 2423 mg h-1 hen-1), followed by CCs (2835 ± 877 mg h-1 hen-1) and ECs (2597 ± 949 mg h-1 hen-1). Furthermore, the EC system had the lowest average CH4 emissions (0.93 ± 0.54 mg h-1 hen-1), while CC (1.07 ± 0.41 mg h-1 hen-1) and CF (1.27 ± 1.11 mg h-1 hen-1) facilities had higher values. Emissions of N2O were similar across all three systems (0.04 to 0.05 ± 0.05 mg h-1 hen-1). The study revealed significant differences in NH3 emissions among CC (2.0 ± 1.0 mg h-1 hen-1), EC (2.5 ± 2.0 mg h-1 hen-1), and CF egg production systems (11.2 ± 15.9 mg h-1 hen-1).
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 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".