TAGRA 2025

This study provides a comprehensive assessment of the macro- and micromorphological changes in yak (Bos grunnies) hindlimb muscle during storage under refrigeration (+4 °C) and freezing (-22 °C) conditions. Meat is a complex, nutritionally valuable food source, composed of muscle fibers, fat, connective tissue, blood, nerves, and vascular structures, with its quality dependent on the structural interplay among these components. Muscle and fat tissues are particularly critical in determining nutritional and functional properties. For experimental analysis, approximately 500 g of hindlimb muscle were collected from three yaks. An initial 50 g sample was fixed in 10% neutral buffered formalin as a control. The remaining tissue was subdivided into 12 samples of 50 g each, allocated to refrigeration (six samples) and freezing (six samples), and stored in dedicated plastic containers. Histological sections were prepared and stained using hematoxylin-eosin. The results revealed distinct macro- and micromorphological features, providing a detailed reference for veterinary-sanitary evaluation and for differentiating pathological changes in muscle tissues of varying origins. Refrigerated yak muscle should be stored for no longer than 7–10 days, as prolonged refrigeration leads to significant structural deterioration and promotes microbial growth, including pathogenic species. In frozen storage exceeding two months, muscle fiber deformation intensifies, accompanied by autolytic processes, inevitably resulting in qualitative deterioration. These findings provide standardized morphological data that can serve as a reference in future studies on meat quality, storage practices, and muscle tissue integrity in wild ungulates. The study emphasizes the critical influence of storage conditions on preserving the structural, nutritional, and hygienic properties of game meat.