Effects of multi-strain RISCO–NUTRIFOUR (RNFS) probiotics (with phytochemicals) and their administration mode on breast meat quality, carcass traits and growth efficiency of broilers over a 42-day cycle

This study evaluated the effects of a novel RISCO–NUTRIFOUR (RNFS) probiotic mixture on breast meat quality, texture profile, sensory traits, physicochemical parameters, carcase characteristics and growth efficiency of broilers over 42 d. A total of 288 1-d-old Ross 308 broiler chicks were randomly allocated to six dietary treatments with eight replicates of six birds each. Treatments included RNFS at 0.4%, 0.2% and 0.1% (T1–T3), 0.1% <i>Bacillus subtilis</i> (T4), 0.1% <i>Saccharomyces cerevisiae</i> (T5) and a negative control (T6). Probiotics were administered <i>via</i> drinking water from day 1 to 14 and through feed from day 15 to 42. Breast meat indices were measured at day 42, and performance index (PI), feed efficiency (FE) and European production efficiency factor (EPEF) were calculated from days 1 to 42. Results showed that RNFS, containing 7 microbial strains and antioxidant bioactive phytochemicals, exerted synergistic effects to improve meat quality and growth. Thus, RNFS supplementation, particularly at 0.1%, significantly (<i>p</i> &lt; 0.05) improved meat water-holding capacity (WHC) and reduced cooking loss (CL) compared to the negative control. Also, supplementation with 0.1% RNFS significantly improved growth efficiency, as indicated by a 10% increase in PI and EPEF compared to the negative control and a 15% improvement relative to <i>Saccharomyces cerevisiae</i> treatment. However, texture profile, sensory attributes and carcase traits remained statistically unaffected. In conclusion, these findings suggest that RNFS, especially at a 0.1% inclusion rate, can enhance certain meat quality and growth efficiency in broilers without adverse effects on carcase yield or sensory acceptability. RISCO–NUTRIFOUR (RNFS) at 0.1% significantly enhanced water-holding capacity by 12.6%, reduced cooking loss 43.3%, and improving meat pH shelf stability by 2.4%.RNFS at 0.1% significantly enhanced growth efficiency (PI and EPEF) by 10% compared by negative control and by 15% compared by <i>Saccharomyces cerevisiae</i>.No adverse effects were observed on carcase yield, texture profile, or sensory traits.RNFS outperformed <i>Bacillus subtilis</i> and <i>Saccharomyces cerevisiae</i> in key meat quality indicators.RNFS at 0.1% group is the best for meat quality and growth efficiency RISCO–NUTRIFOUR (RNFS) at 0.1% significantly enhanced water-holding capacity by 12.6%, reduced cooking loss 43.3%, and improving meat pH shelf stability by 2.4%. RNFS at 0.1% significantly enhanced growth efficiency (PI and EPEF) by 10% compared by negative control and by 15% compared by <i>Saccharomyces cerevisiae</i>. No adverse effects were observed on carcase yield, texture profile, or sensory traits. RNFS outperformed <i>Bacillus subtilis</i> and <i>Saccharomyces cerevisiae</i> in key meat quality indicators. RNFS at 0.1% group is the best for meat quality and growth efficiency