Influence of calcium source and a novel microbial phytase on broiler performance and bone

Introduction The total dietary Ca requirement for broilers has previously been determined using limestone, monoor di-calcium phosphate, and in the presence of dietary phytate (Bar et al., 2003). Phytate has been reported to increase the total dietary Ca requirement of chickens from 0.50% to 0.95% (Nelson et al., 1968). The use of exogenous phytase promotes phytate hydrolysis and allows for a marginal reduction in dietary Ca without negatively influencing growth performance (Dilger et al., 2004). Other factors such as Ca source and particle size, may also influence the total dietary Ca requirement of broilers. For example, total dietary Ca may be substantially reduced when young broilers are fed a highly soluble source of Ca (Vistacal, AB Vista Feed Ingredients, Marlborough, UK) in the presence of a novel microbial phytase (Quantum Blue, AB Vista Feed Ingredients, Marlborough, UK; Walk et al., 2012).