Effects of dietary levels of 6-phytase on performance, nutrient digestibility, and tibia ash of broiler chickens fed corn–soybean meal-based complex diet

This study evaluates phytase’s impact on broiler performance. Two thousand Ross 308 broilers were randomly assigned to 5 treatments based on body weight, with 40 birds per replicate pen and 10 replicate pens per diet. The 39-day experiment followed a four-phase feeding: starter 1 (days 0–4), starter 2 (5–11), grower (12–25), and finisher (26–39). The five treatments include basal diet 0 FTU/kg phytase (CON), CON + 500 FTU/kg (500 FTU/kg), CON + 750 FTU/kg (750 FTU/kg), CON + 1000 FTU/kg (1000 FTU/kg), CON + 1500 FTU/kg (1500 FTU/kg). The body weight increased ( p < 0.05) from starter 2 to finisher, and overall phase in the phytase-supplemented diets. Feed conversion ratio and mortality rate were lower ( p < 0.05) in the starter 2 and starter 1, respectively, in the phytase-supplemented diets. On day 24, the retention of phosphorous increased ( p < 0.05) when the supplementary level of phytase increased from 500 to 1500 FTU/kg. Furthermore, on day 39, the digestibility of dry matter, calcium, and phosphorus increased ( p < 0.05) as the level of phytase increased. The level of tibia ash and myo-inositol increased ( p < 0.05) in the phytase-supplemented diets. We concluded that increasing phytase doses from 500 to 1500 FTU/kg improved broiler performance over CON.