ABSTRACT
The biological process of avian incubation is the culmination of species-specific behavioural and physiological traits that have been studied and documented for over two hundred years (Reaumur, 1749, as cited by Henderson, 1939). It was recognized by Dareste (1891), and later confirmed by Eycleshymer (1907), that the parental movement of eggs was necessary to prevent embryonic attachment to the shell, resulting in embryonic mortality. From a commercial perspective, similar observations were subsequently confirmed by Martin and Insko (1935) in turkeys and Kaltofen (1961) in chickens where low or reduced rate of egg turning increased early embryonic losses. It is now well recognized that numerous factors influence the overall process of successful embryonic development (Landauer, 1967).
