# Carcass Yield and Meat Quality of Broiler Chicks Supplemented with Yeasts Bioproducts
## 4 Discussion  
No research appears to have been reported on the effect of inactive _Rlodotorula uncaliagnosa_ biomass supplementation on broilers' carcass yield and meat quality. Furthermore, our study's aim could be considered as a novel applied investigation subject, providing new insights on valuable microbial pigment additives usage in poultry nutrition. In this study, the yeasts dietary supplementation affected the gizzard weight and the abdominal fat deposits of broiler chicks. Gizzard weight was significantly influenced by the highest level of SC supplementation (1.3 g/kg feed), when compared with all experimental groups. Lower abdominal fat deposits were observed by increasing the level of SC dietary supplementation (up to 1.3 g/kg diet). Similar to our findings, [PERSON]'s results [17] suggest that supplementing different levels of SC dietary supplements significantly affects the broiler chicks' gizzard weights and abdominal fat accumulations. Relying on our previous results [18], a possible explanation could be attributed to the SC growth promotive effect, having a direct correlation between the final live body weight and the abdominal fat deposits, rather than lipogenic modulative effects, having no correlation with the broilers' serum triglycerides nor with their serum cholesterol. In our study, pH was not influenced by the inactive yeasts dietary supplementation. The raw broiler meat pH mean values ranged for raw breast (5.97-6.02) and thigh (5.91-6.02) and fitted in the 24 h raw refrigerated broiler's meat normal range of values [31; 32] without abnormality encounters such as pale soft exudative and wooden-like meat characteristics. Generally, the meat pH is an important quality indicator, firmly associated with slaughtering, meat processing, and storage management. In addition, meat pH is strongly correlated with color and appearance attributes [19], indicating the main meat quality characteristics and abnormalities. It is known that darker breast meat is related to high pH values [20; 32]. Color is an important meat attribute since it is directly influencing the consumer's perception, often associated with meat freshness [33] and rearing nutritional conditions [34]. Results obtained on this work suggest that dietary supplementation of SC increases the meat brightness and total color differences (\(p<0.05\)), causing the meat's visual appearance to shift to a paler nuance, when compared with the control group. In accordance with our findings, [PERSON] et al. [35] found that yeast dietary supplementation increases the broiler meat lightness (\(L^{*}\)). However, a recent study [36] reports that live _Saccharomyces sp_. supplementation decreases effects on the lightness (\(L^{*}\)) and yellowness (\(b^{*}\)) attributes, and increases the broiler chickens meat redness (\(a^{*}\)). Moreover, red yeast (RM) dietary supplementation had a major influence on the broiler meat color parameters. Previous studies confirm our results [37; 38], indicating significant effects of red yeast administration on broiler's meat brightness (\(L^{*}\)) and pronounced redness nuance (\(a^{*}\)). A brief explanation for the opposite effect and the color variations in this study concerning the RM dietary supplement on the broiler breast and thigh meat brightness could be attributed to the RM carotenoid complex, mainly constituted by the xanthophylls (torularhodin) and less carotenoids (\(\beta\)-carotene) [39], which has a greater pigmentation capacity [40], thus, directing the broiler carotenoid metabolism towards retinol accumulation via \(\beta\)-carotene conversion and extending the flesh and skin xanthophylls deposits [35]. The broiler meat color was significantly influenced by both SC and RM supplementation, presenting an interaction (\(p<0.05\)) with the thigh meat \(L^{*}\), \(a^{*}\), \(b^{*}\), C, BI, YI, and \(\Delta\)E. The broiler thigh meat lightness, redness, chroma, and total color values were increased, while the yellowness, yellow index, and browning index were decreased, when comparing all experimental groups.