Synergistic effects of RISCO–NUTRIFOUR probiotic mixtures as feed additives on growth performance and carcase characteristics of broiler chickens over 28 days

Antibiotic substitutes in the feed can have a positive effect on performance and carcase characteristics and lead to healthier chicks with higher body weight. To investigate the effects of feed-based probiotic RISCO–NUTRIFOUR^® solution (RNFS) at different doses on performance parameters and carcase attributes of broilers. A total of 288 Ross 308–day-old birds were treated with basal diet at six dietary treatment levels (T1–T3 = basal diet with RNFS at level 1, 2, or 3) (0.4%, 0.2%, and 0.1% RNFS/ton feed), T4= basal diet with <i>Bacillus subtilis</i> ‘CLOSTAT^®’, T5= basal diet with <i>Saccharomyces cerevisiae</i> (Baker’s yeast), and T6= basal diet without addition (negative control). Performance indicators were estimated during 0–14, 14–28, and 0–28. On day 28, the absolute and relative weights of carcase characteristics were evaluated. Broilers fed RNFS diets, particularly at level 3, were heavier at 28 days, acquired more weight, and converted feed more efficiently to meat, to a degree higher than the CLOSTAT or Baker’s yeast groups. Throughout the study, the feed treatments had no effect on absolute or relative carcase weight, with the exception of relative breast and leg weights. In conclusion, feeding probiotics RNFS, especially at low doses (0.1% “1 L/ton”), was able to maximise broiler performance while maintaining carcase characteristics.HighlightsBroilers reared to 28 days of age and treated with probiotics RNFS on a feed basis, especially at level 3 (1% RNFS), exhibited higher body weight, breast, and leg yields.In broilers treated with feed-based probiotics RNFS, especially at level 3, daily weight gain was improved during days 14–28 and the entire period.The use of RISCO–NUTRIFOUR^® probiotics at level 3 (1 L RNFS/ton) at 14–28 days of age is recommended on a feed basis to optimise an overall conversion of feed to meat. Broilers reared to 28 days of age and treated with probiotics RNFS on a feed basis, especially at level 3 (1% RNFS), exhibited higher body weight, breast, and leg yields. In broilers treated with feed-based probiotics RNFS, especially at level 3, daily weight gain was improved during days 14–28 and the entire period. The use of RISCO–NUTRIFOUR^® probiotics at level 3 (1 L RNFS/ton) at 14–28 days of age is recommended on a feed basis to optimise an overall conversion of feed to meat.