Meta-analysisindependent cross-checkabstract checked I-RES-112 standard review
Antibiotic growth promoters improve feed efficiency by only about 3%
Effect of antibiotic growth promoters (AGPs) on feed conversion ratio (FCR) of broiler chickens: A meta-analysis.
Overview
El-Fateh M et al.. Poult Sci 2024 · PMID 39504822 · DOI 10.1016/j.psj.2024.104472
On average, antibiotics improved feed conversion by 2.8%, with large variation.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
What is the overall effect of AGP on FCR in broilers?
- How was the study done?
Meta-analysis with meta-regression (PRISMA)
- How many people, animals or samples were studied?
42 articles, 74 experiments, 19,562 chickens
- What was actually found?
Overall FCR improvement 2.8% (95% CI 1.3-4.3%; prediction interval -10 to 16%). Breed, dose and location explained 53% of variation.
- How large was the observed effect?
Overall FCR improvement 2.8% (95% CI 1.3-4.3%; prediction interval -10 to 16%). Breed, dose and location explained 53% of variation.
- What do the results mean in everyday life?
Antibiotics are a minor factor in how fast chickens grow today.
- What are the study's limitations?
Heterogeneous studies; FCR only
- What does it say about Elawady's specific claim?
Supports use for growth; limits its importance.
- Do the results apply to Germany and Europe?
EU: banned.
- What can explicitly not be concluded from this study?
Does not measure residues or human effects.
Scientific in-depth review
1. Full reference
- Authors
- El-Fateh M et al.
- Journal
- Poult Sci
- Year
- 2024
- Identifier
- PMID 39504822 DOI 10.1016/j.psj.2024.104472
- Verification
- verified – PubMed efetch 2026-10-26; Crossref 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
not stated in abstract
2. Research question
What is the overall effect of AGP on FCR in broilers?
3. Study design and population
- Study design
- Meta-analysis – Meta-analysis with meta-regression (PRISMA)
- Population
Broilers in 74 experiments
- Country
multinational
- Period
literature to 2024
- Sample size
42 articles, 74 experiments, 19,562 chickens
- Inclusion and exclusion criteria
as described in the abstract
4. Methods and endpoints
- Exposure / intervention
AGP supplementation
- Comparator
Diets without antibiotics
- Endpoints
Feed conversion ratio
- Statistical methods
as reported in the abstract
5. Actual results
- Results
Overall FCR improvement 2.8% (95% CI 1.3-4.3%; prediction interval -10 to 16%). Breed, dose and location explained 53% of variation.
- Absolute risks
not reported
- Authors' conclusion
An overall marginal improvement with wide variation; the authors recommend against using AGP.
6. Strengths
- Prediction interval reported
- Meta-regression
7. Weaknesses
- Heterogeneous studies
- FCR only
8. Risk of bias
- Orienting tool
- AMSTAR 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Abstract only.
9. Assessment of the statistical interpretation
Average effect small; prediction interval includes harm and benefit (stats/C-RES-05_agp.py).
10. Relevance to the specific claim
Quantifies the size of the growth-promoting effect.
11. Independent contrary findings
12. Transferability to Germany and Europe
13. Overall methodological judgement
On average, antibiotics improved feed conversion by 2.8%, with large variation.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | moderate |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
15. Linked fact checks
- Antibiotics were (and are) used in poultry production to make chickens grow faster. – Studies with mixed or unclear results