Abstract
Gene markers for tenderness have been shown to be related to shear force of meat from cattle (Barendse et al., 2008; Page el al., 2002; White el al., 2005). Four tenderness markers currently available commercially are based on polymorphisms in genes controlling components of the post-mortem tenderisation process, specifically the calpain proteolytic system. The objectives of this study were to quantify the magnitude of effects of tenderness gene markers on growth, feed efficiency, carcass characteristics and beef quality in Brahman cattle, and to quantify interactions within and between tenderness gene markers, gender, hormonal growth promotant, method of carcass hang, and major muscles.