Table 1.
Summary of data collected from the questionnaire and Environment Canada weather stations for the analysis of the occurrence of breast myopathies.
Table 2.
Descriptive statistics of 15 continuous variables from 37 chicken broiler flocks surveyed in a study on the occurrence of breast meat myopathies in Ontario, Canada (2019–2020).
Table 3.
Descriptive statistics of 18 categorical variables from 37 chicken broiler flocks surveyed in a study on the occurrence of breast myopathies in Ontario, Canada (2019–2020).
Fig 1.
Pie charts illustrating the prevalence of spaghetti meat (SM), woody breast (WB), and white striping (WS).
The prevalence of SM (SM1) was 36.3%. The prevalence of moderate WB (WB1) was 70.5%, and the prevalence of severe WB (WB2) was 11.8%. The prevalence of mild WS (WS1) was 93.8%, and the prevalence of moderate WS (WS2) was 2.2%. There was no severe WS (WS3) observed in our samples (n = 9,250; average live weight at slaughter: 2.36 kg).
Fig 2.
Venn diagram illustrating the incidence counts of spaghetti meat (SM), woody breast (WB), and white striping (WS) in 9,250 fillets.
A total of 7,876 fillets presented multiple myopathies together. Within 7,876 fillets, 3,038 fillets presented SM and WB and WS together. Out of 9,250 scored fillets, only 305 fillets did not show myopathies. SM0: SM absent, SM1: SM present. WB0: WB absent, WB1: WB moderate, WB2: WB severe. WS0: WS absent, WS1: WS mild, WS2: WS moderate.
Fig 3.
Seasonal variations in the prevalence of spaghetti meat (SM) and severe woody breast (WB2).
A total of 4,750 fillets (19 flocks) were scored at a processing plant that employs air-chilling. The prevalence of SM1 was the highest during the summer (39.8%), whereas the prevalence of WB2 was the highest during spring (26.6%). Different letters above bars indicate significant differences among groups (Kruskal Wallis test with Dunn’s test for multiple comparisons, p < 0.05) of SM, and WB in each season.
Table 4.
Results of the final random intercept 2-level (flock-fillet) multivariable logistic regression model for spaghetti meat, in a cohort of 9,250 chicken breast fillets collected at two processing plants between 2019–2020 in Ontario, Canada.
Table 5.
Results of the final random intercept 2-level (flock-fillet) multivariable regression model for woody breast, in a cohort of 9,250 chicken breast fillets collected at two processing plants between 2019–2020 in Ontario, Canada (n = 9,250 fillets).