Anotace:
The impact of age, live weight, and growth rate of the bulls of Ukrainian breeds on the area of “muscle eye” (cross-section of m. longissimus dorsi when the carcass is divided into front and rear between the 12th and 13th ribs) was studied. The correlation between the size of the “muscle eye” and the carcass's characteristics and the meat's qualitative indicators was also determined. The research was conducted on the bulls of Ukrainian black-and-white dairy (UBWDB) and Ukrainian meat (UMB) breeds. Living animals “muscle eye” area was determined with the ultrasonic analyser Emperor 860, after slaughter. It was found that UMB bulls have the area of “muscle eye” twice as big as their UBWDB peers. The “muscle eye” area increases when growing the cattle to 400 – 450 kg. In the future, it will be practically independent of the age and weight of the animals and remains stable. An increase in the average daily gains within the breed leads to an increase in the “muscle eye” area. The area of “muscle eye” has a weak negative connection (r = -0.193) with meat tenderness and dry matter content (r = -0.345) and a positive one with slaughter weight (r = 0.614) and slaughter yield (r = 0.653). Of the three parameters (length, depth, and area) of “muscle eye”, the greatest impact on the technological properties of meat has depth. Its increase has a negative connection with meat tenderness (r = -0.810) and moisture (r = -0.474), but it has a positive impact on the moisture retention capacity (r = 0.338) and weight of weighed portion after heat treatment. The obtained results can be used to clarify the optimal growing parameters of the bulls of Ukrainian black-and-white dairy and meat breeds for meat and determine the optimal age and live weight of the cattle slaughter.