Fear responses and postmortem muscle characteristics of turkeys of two genetic lines

Abstract

Commercial turkey production has increased greatly in recent decades. Along with increased production, problems with turkey meat quality have also increased. Research with other species has demonstrated that differences in meat quality exist among pigs and cattle differing in characteristics such as fearfulness. However, associations between fear responses and postmortem (PM) muscle characteristics related to the meat quality of turkeys have not been examined. This study evaluated the test–retest repeatability of responses of male commercial (COMM) and randombred (RB) turkeys in an open field (OF) test, which is used to assess fear and activity levels of poultry. Another objective of this study was to evaluate the relationship between behavioral OF responses and PM breast muscle characteristics (pH and R-value) that are related to meat quality. Thirdly, this study evaluated differences in pH and R-value between the turkey lines. Male COMM and RB turkeys were each housed in groups in 4 pens. Turkeys were individually tested in an OF (2.74 × 2.74 m, divided into 81 squares) at 1, 4, and 11 wk (COMM N = 27; RB N = 33). Turkeys were then grouped into clusters based on a cluster analysis of OF behavior. Turkeys were processed and meat quality characteristics were evaluated at 15–17 wk for COMM and 20–21 wk for RB turkeys. Results were analyzed using a mixed model (SAS 9.4). Breast muscle pH and R-value did not differ between genetic lines, and there were no differences in pH and R-value among clusters within genetic lines. These findings suggest that OF responses measured during rearing are not related to PM breast muscle pH and R-value, which ultimately affect meat quality. Further research is needed to assess whether other types of fear responses are associated with meat quality and whether differences in R-value between genetic lines are associated with differences in other meat quality characteristics.