Cross-sectional studyindependent cross-checkabstract checked I-CHK-108 standard review
About 1 in 8 chicken breasts in Ontario were severely 'woody'
Prevalence of breast muscle myopathies (spaghetti meat, woody breast, white striping) and associated risk factors in broiler chickens from Ontario Canada.
Overview
Che S et al.. PLoS One 2022 · PMID 35427383 · DOI 10.1371/journal.pone.0267019
Severe woody breast affected 11.8% of fillets, and almost all fillets had white striping.
Does the study support the specific claim? Yes · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
How common are breast myopathies in Ontario broilers and what are the risk factors?
- How was the study done?
Cross-sectional prevalence survey of fillets from 37 flocks with flock-level risk factors
- How many people, animals or samples were studied?
9,250 fillets (250 from each of 37 flocks)
- What was actually found?
Prevalence: spaghetti meat 36.3% (35.3-37.3), severe woody breast 11.8% (11.2-12.5), mild/moderate white striping 96.0% (95.6-96.4); 85.1% of fillets had multiple myopathies. WB odds increased with live weight (OR 1.23; 1.03-1.47) and in flocks not vaccinated against coccidia (OR 1.86; 1.51-2.29).
- How large was the observed effect?
Prevalence: spaghetti meat 36.3% (35.3-37.3), severe woody breast 11.8% (11.2-12.5), mild/moderate white striping 96.0% (95.6-96.4); 85.1% of fillets had multiple myopathies. WB odds increased with live weight (OR 1.23; 1.03-1.47) and in flocks not vaccinated against coccidia (OR 1.86; 1.51-2.29).
- What do the results mean in everyday life?
Woody breast is common in fast-growing chickens, but most breasts are not severely affected.
- What are the study's limitations?
One province; CIs do not appear to account for clustering by flock (stats/C-CHK-03_woody_breast.py)
- What does it say about Elawady's specific claim?
Supports the existence and frequency of the condition; links it to growth, not antibiotics.
- Do the results apply to Germany and Europe?
Same fast-growing hybrids are used in the EU; prevalence may differ.
- What can explicitly not be concluded from this study?
Says nothing about human health effects.
Scientific in-depth review
1. Full reference
- Authors
- Che S et al.
- Journal
- PLoS One
- Year
- 2022
- Identifier
- PMID 35427383 DOI 10.1371/journal.pone.0267019
- 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
How common are breast myopathies in Ontario broilers and what are the risk factors?
3. Study design and population
- Study design
- Cross-sectional study – Cross-sectional prevalence survey of fillets from 37 flocks with flock-level risk factors
- Population
Commercial broiler flocks (2 processing plants)
- Country
Canada
- Period
May 2019-March 2020
- Sample size
9,250 fillets (250 from each of 37 flocks)
- Inclusion and exclusion criteria
as described in the abstract
4. Methods and endpoints
- Exposure / intervention
Flock factors (live weight, temperature, vaccination)
- Comparator
Flocks without the factor
- Endpoints
Prevalence of spaghetti meat, severe woody breast, white striping
- Statistical methods
as reported in the abstract
5. Actual results
- Results
Prevalence: spaghetti meat 36.3% (35.3-37.3), severe woody breast 11.8% (11.2-12.5), mild/moderate white striping 96.0% (95.6-96.4); 85.1% of fillets had multiple myopathies. WB odds increased with live weight (OR 1.23; 1.03-1.47) and in flocks not vaccinated against coccidia (OR 1.86; 1.51-2.29).
- Absolute risks
not reported
- Authors' conclusion
High prevalence of myopathies; environmental conditions and husbandry are associated with their development.
6. Strengths
- Random fillet sampling from many flocks
- Representative design claimed
7. Weaknesses
- One province
- CIs do not appear to account for clustering by flock (stats/C-CHK-03_woody_breast.py)
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Observational risk-factor analysis.
9. Assessment of the statistical interpretation
Severe WB in about 1 of 8 fillets; risk rises with bird weight. Reported CI equals a simple binomial CI, so precision is overstated.
10. Relevance to the specific claim
Quantifies how often 'woody' breast occurs in modern fast-growing broilers.
11. Independent contrary findings
12. Transferability to Germany and Europe
13. Overall methodological judgement
Severe woody breast affected 11.8% of fillets, and almost all fillets had white striping.
| 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
- Because of intensive production, modern chicken breast has become 'like wood' (woody breast). – Studies supporting the claim