MORPHOLOGICAL ASPECTS OF GROWTH IN SUBCUTANEOUS AND INTRAMUSCULAR ADIPOCYTES IN CATTLE

The accumulation of subcutaneous fat and intramuscular fat storage (ma rbling of meat) are the results of both hypertrophy and hyperplasia of fat cells. The growth related changes in the fat cell diameter are pr esented under the influence of endogenous and exogenous factors. 60 bu lls of the breeds White-Blue Belgians (WBB), German Angus (DA), Gallow ay (Ga) and Black Pied (SR) were grown up to the age of 24 months and then slaughtered. 10 bulls of each breed were slaughtered at the age o f 2, 4, 6, 12 and 24 months. Shot biopsy samples and post mortem muscl e were used to measure the adipocyte diameter and computer image analy sis of the intramuscular fat islands. The hypertrophy of the subcutane ous fat cells shows characteristic growth curves, that are influenced by breed and nutrition. The increase in number and the enlargement of the intramuscular fat islands could have caused by proliferation and d ifferentiation processes of the adipocytes contributing to the breed s pecific shaping of the marbling clearly. Future examinations should ex plore the regulation of differentiation of adipocytes on cellular and molecular level, as a basis for innovative methods of the farm animal breeding, for the improvement of product quality.