Energy and nutrient intake on white striping, wooden breast and carcass composition in broilers from three genetic lineages at different ages

Increased incidence of myopathies and/or changes in broiler carcass composition leads to poor visual appearance and carcass condemnation on the slaughter line, or even subsequent consumer product rejection, consequently, economic losses. This study,was set to assess the incidence of white striping (WS), wooden breast (WB) and the carcass composition of three different genetic lineages of broilers fed with three different dietary nutrient densities. The experiment was conducted with a 4320 broilers, in a completely randomized, 3 × 3 factorial design, assessing three genetic lineages (Embrapa 021 – moderate growth, Cobb 500 and Ross 308 – rapid growth) and three dietary nutrient densities (ND): low, medium and high. Pelleted feed and water were consumed ad libitum. Daily digestible lysine intake (DdLysI – g/d), daily apparent metabolizable energy (DAMEI – kcal/d) and average daily weight gain (ADWG - g/d) were recorded for each evaluation period. At the ages of 28, 35, 42 and 49 days, 16 animals per treatment were slaughtered and submitted to WS, WB and carcass composition analysis. Ordinal logistic regression was used to analyse the WS and WB data. DdLysI, DAMEI, ADWG and carcass composition data were subjected to analysis of variance and the means compared by Tukey’s test at a 5% significance level. An interaction effect (P