Location: Quality and Safety Assessment Research UnitTitle: Relationship between the woody breast and white striping myopathies in broiler breast meat
Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/14/2018
Publication Date: 7/23/2018
Citation: Bowker, B.C., Zhuang, H., Yoon, S.C. 2018. Relationship between the woody breast and white striping myopathies in broiler breast meat. Poultry Science Association Meeting Abstract. 97:223.
Technical Abstract: The woody breast (WB) and white striping (WS) myopathies that occur in the Pectoralis major muscles of broilers are both associated with the fast growth rate and large size of modern broilers. These myopathies often occur in the same breast fillet. The two myopathies seem to have similar effects on the histology and composition of the muscle tissue. However, the relationship between these two myopathies is not well defined. The objective of this study was to evaluate the relationship of the occurrence and degree of severity between the WB and WS myopathies in broiler breast fillets. Over 2800 breast fillets were collected from the deboning line of a commercial processing plant that slaughters large broilers (3.6-4.1 kg live weight). Individual breast fillets were weighed and assessed independent WB and WS scores from 1.0 to 3.0 in 0.5 score increments (normal = 1; moderate = 2; severe = 3). Data were analyzed using chi-square, frequency, and correlation analysis. Chi-square analysis indicated that there was a significant relationship between the WB and WS conditions (P < 0.0001). Approximately 94% of all WB fillets (WB score = 1.5) also exhibited WS. Of the fillets that did not exhibit WB, 54% exhibited WS. Of the fillets that exhibited severe WB, 28% had severe WS, 51% had moderate WS, and 21% had mild or no WS. Approximately 83% of all WS fillets (WS score = 1.5) exhibited WB. Of the fillets that did not exhibit WS, 26% exhibited WB. Of the fillets that exhibited severe WS, 41% had severe WB, 46% had moderate WB, and 13% had mild or no WB. Overall, there was a significant positive correlation between WS and WB scores (r = 0.55, P < 0.0001), but the incidence of the myopathies varied by fillet weight. Fillet weight (465 ± 91 g) was moderately correlated to WB (r = 0.44, P < 0.0001) and WS (r = 0.32, P < 0.0001) scores. For fillets less than 407 g (lowest quartile range), 27% of fillets had moderate or severe WS and 22% of fillets had moderate or severe WB. However, for fillets > 528 g (highest quartile range), 70% of fillets had moderate or severe WS and 77% of fillets had moderate or severe WB. The strength of the relationship between WS and WB scores changed with fillet weight (r = 0.63 for fillets < 407 g; r = 0.51 for fillets 407-469 g; r = 0.43 for fillets 469-528 g; r = 0.39 for fillets > 528 g). Data suggest that although the occurrence of the WS and WB myopathies in breast fillets are closely related, breast fillets exhibiting WS without WB are more likely to be observed than WB fillets without WS. Furthermore, data suggest that the strength of the relationship between the WB and WS myopathies in breast meat from large broilers is influenced by fillet weight.