Effects of supplemental phytase on the mineral content in tibia of broilers fed different cereal based diets

A 21-day experiment with day-old broilers was conducted in order to assess the effect of phytase supplementation to cereal-soybean meal based diets on the mineral content in tibia (Ca, P, Fe, Mg, Cd, Zn). Diets were formulated to contain 4 different cereals (maize, wheat, triticale and barley), 2 levels of dietary calcium (0.6 and 1.0%) and 3 levels of supplemental phytase (0, 500 and 1 000 PU/kg). Supplemental phytase increased the mineral levels in tibia. A statistically significant increase was observed for Fe (P < 0.024) and Mg (P < 0.024), but not for Ca, P, Cd and Zn contents in tibia. In the case of Fe and Mg contents significant cereal × phytase interactions were also observed (P < 0.036 and 0.002, respectively). Cereals influenced the contents of Fe (P < 0.0001), Mg (P < 0.0001), Cd (P < 0.0001) and Zn (P < 0.003) while dietary calcium levels affected only calcium content (P < 0.008).