This means, potentially, that less calcium (Ca) is available for eggshell calcification (Rao & Roland, 1989; Roberts, 2004) and some producers have been confronted with serious shell quality problems.Hence, poor eggshell quality has been a major economic concern to commercial egg producers with serious economic losses due to levels of downgraded eggs ranging from 6% to 20% (Roland, 1988; Keshevarz & Nakajima, 1993; Hunton, 2005).