Bakeretal.(1981a,b)postulatedthatmaximuminvolution of the reproductive organs is essential for optimum postmolt performance. Variability of BW loss, and therefore differing degrees of reproductive involution, was suggested as an explanation for the conflicting results obtained by investigators using similar molting procedures. Loss of primary flight feathers also has been used as an indicator of the completeness of reproductive involution (Kreuger et al., 1977). However, some techniques such as molting by high dietary I may not cause any loss of feathers (Arrington et al., 1967). Hansen(1960)andLenetal.(1964)reportedanassociation between improvements in both postmolting egg quality and production and the length of the rest period. The degree of improvement in postmolting performance was associated with an increase in the number of days during which no eggs were produced. Baker (1981) and Baker et al. (1981a,b) found that improvements in postmoltingperformancewereassociatedwithincreasingBW loss of hens up to 31% of original BW. Hens that lost the greatestamountofweightexhibitedthegreatestimprovements in eggshell quality and highest egg production after molting. Reduction of BW beyond 35% may exert detrimental effectsonlifeofflockeggproduction.Althoughpostmoltingeggproductioncontinuedtoimprovewithincreasing BW loss beyond 30%, the recovery period, during which no eggs were produced, was prolonged such that overall eggnumberswerereducedforthelifeoftheflock(Carter and Ward, 1981).