Large White turkey hens were housed in light-controlled pens in molting experiments. In each experiment, a group of hens was molted (MO) and nonmolted control hens (CON) were maintained in an adjacent room. Body weight and absolute and relative weights (g organ weight/100 g body weight) of the ovary with ova, oviduct, and liver were observed in MO and CON throughout the molting period and after photostimulation. Further determinations were made of the percentage of liver dry matter (PLDM) and ash (PLA). The MO hens lost body weight during feed deprivation but regained it and continued to gain body weight until they were heavier at the beginning of the second cycle than at the end of the first cycle. Hematocrit and body temperature of MO hens exhibited significant (p less than or equal to .05) changes during molt. Hen-day egg production averaged 44.7% +/- 1.3 during the second cycle. Mean value for eggs per hen-housed was 62.6 +/- 1.8. Egg weight remained constant (96.8g +/- .2 g) and egg specific gravity averaged 1.076 +/- .0001 in MO hens. The molt was characterized by significantly (P less than or equal to .05) reduced relative liver weight during feed deprivation, decreased relative ovary and oviduct weights that did not begin to increase until after photostimulation. No consistent differences were observed in PLDM or PLA.

One hundred Medium White turkey hens were randomly placed in cages, photostimulated, and provided a breeder diet and water ad libitum. Once egg production began, eggs were collected daily for 19 weeks. When the first egg laying cycle was completed, 95 hens were moved to floor pens and molted to observe the effects of different body weight losses during the molt on the second egg production cycle. Hens were randomly distributed between replicate pens of two treatment groups and exposed to 24 hr of light per day for 7 days. The photoperiod was then reduced to 6 hr for the remainder of the molt. Water was removed for 3 days and feed was removed for 7 and 18 days, respectively, until a reduction in body weight of 10% for the first Treatment (TRT 1) or 20% for the second treatment (TRT 2) was reached. Upon reaching desired body weight loss, hens were fed a holder diet for 5 weeks, then a prebreeder diet for 2 weeks. All hens were then randomly placed in cages, fed a breeder diet ad libitum, and subjected to a 14-hr/day photoperiod for a 20-week laying cycle. Packed cell volume increased during water deprivation during the molt. Body weights were not different at lighting for the second cycle.Production was signifcantly higher for birds with lower weight loss. Percent hen-housed egg production and total eggs per hen-housed bird were significantly (P< .01) greater in TRT 1 than TRT 2. Percent hen-housed egg production and total eggs per hen-housed bird were significantly (P<.01) greater in the second cycle than in the first cycle. (