meal phytate by MP and acid phosphatase at 40°C reported
by Zyla and Koreleski (1993). However, in subsequent
studies by the same authors, phytase addition
could not completely dephosphorylate phytates in corn–
soybean meal diets under simulated turkey gastrointestinal
tract conditions (Zyla et al., 1995). The lack of
intestinal microorganisms in the in vitro system and
the high calcium content of the diet could explain the
incomplete in vitro phytate hydrolysis in the current
study and that of Zyla et al. (1995). It has been reported
that phytate hydrolysis is greatly reduced as calcium
content of the diet is increased (Ballam et al., 1985)