Morphological composition and quality characteristics of carcasses of Ukrainian Black-and-White dairy breed bulls depending on muscle tissue colour

In numerous global standards, muscle tissue colour is used as a key criterion in evaluating the quality of beef carcasses and determining their market value. The relevance of this study lies in establishing the relationship between beef colour and carcass quality characteristics. The objective was to determine slaughter metrics, morphological composition, and quality traits of carcasses from 18- to 24-month-old bulls of the Ukrainian Black-and-White dairy breed based on muscle tissue colour. Following a 24-hour fasting period with free access to water, the slaughter of bulls was conducted at the slaughterhouse in Kalynivka village, Brovary District, Kyiv Region. Muscle tissue colour was assessed using a seven-point scale by the methodology of the Japan Meat Grading Association. Carcasses were divided into two groups: scores of 1 to 5 (n=24) and scores of 6 to 7 (n = 10). It was established that animals with higher live weight after fasting exhibited superior muscle tissue colour. A tendency is observed towards a reduction in slaughter yield (carcass) by 0.3 percentage points, the proportion of muscle tissue by 0.3 points, including a decrease in extra (by 0.9) and first rates (by 1.3) cuts, fat tissue (by 0.1), bones (by 0.1 points), marbling (by 3.8%), and the loin eye area (by 17.0%). Conversely, the proportion of muscle tissue at the second rate increases by 2.2 points. With a more intense muscle tissue colour, a significant increase (P > 0.999) is observed in the percentage of tendons and ligaments (by 0.5 points), carcass conformation (meatiness) (by 43.3%), fat cover (by 25.0%), subcutaneous fat thickness (by 42.9%), and the colour intensity of fat tissue on the carcass (by 17.8%). The practical significance of this study lies in its applicability for meat processing enterprises to classify carcasses of Ukrainian Black-and-White dairy breed animals according to intended use. Consumers are also provided with additional information for making an informed choice of beef based on the relationship between muscle colour and carcass quality traits