EN
The research material included 96 slaughter rabbit carcasses. Half of them came from the animals managed in small-scale backyard farming units where animals were fed a natural ingredient diet, while the other half was from rabbits kept under commercial production conditions and fed commercial rabbit pellets. The thigh and saddle muscle samples were collected from each carcass to establish a content of ubiquinone (CoQ10) and crude protein along with its collagen level. Determination of tissue coenzyme Q10 (UQ10) was carried out by high-performance liquid chromatography with some modification. Crude protein concentration was estimated using Kjeldahl procedure, while total collagen content by the method of Stegemann modified by Hurych-Chvapil, using hydrolysis according to Möhler and Volley. Ubiquinone level in slaughter rabbit tissue ranged between 76 and 127 µg/g tissue. The studies indicated that rabbit rearing sy stem and muscle type are determinants of CoQ10 content. Meat of rabbits managed under the traditional backyard farming system exhibited higher CoQ10 concentration as compared to that determined in rabbits from the commercial rabbitry. Additionally, the CoQ10 level in the saddle was significantly higher than that in the thigh muscles, and the relationships was noted in both types of rabbit production systems. When the CoQ10 content was expressed per gram of fibrillar protein, there were not significant differences between saddle and thigh muscles. The correlation coefficient between ubiquinone and fibrillar protein averaged to 0.94. The studies also demonstrated a higher protein level in the saddle than in thigh muscles. However, no differences in protein concentration were reported in respect to the rabbit farming system. The protein composition in the saddle muscles, irrespective of a rabbit production system, revealed significantly lower collagen content compared to the proteins in thigh muscles. The obtained results and data from literature provide evidence that rabbit meat, especially from the traditional (organic) management system, is one of the best sources of animal protein and ubiquinone Q10.