This study evaluated the effects of short fasting periods and recovery diet protein levels (CP) on molt response and postmolt productivity in 384 aged Hy-Line laying hens over a 19-week period. A 2 × 3 factorial design was implemented, with two molting procedures (2- or 4-day feed withdrawal followed by corn diet) and three resting diets differing in CP content (15.5%, 11.62%, or 8.5%). Positive (non-molted) and negative (conventional fasted molt) control groups were included for comparison. Egg production (EP) declined rapidly within 3–5 days following molt induction across all experimental groups; however, no significant differences were detected among treatments (P > 0.05). Feed intake (FI) during the molting period was not influenced by the molting procedure or resting diet; however, all factorial treatments differed significantly from the control groups (P = 0.001). The applied molting strategies induced moderate body weight losses (6.2–13.7%), lower than the 26.23% loss observed in the negative control (P = 0.001). During the 5–19-week postmolt period, EP, FI, feed conversion ratio, egg mass, egg weight, and peak EP were not significantly affected by molting procedure or resting diet (P > 0.05). Hens subjected to a 4-day feed withdrawal exhibited superior albumen quality during early recovery (P = 0.008), whereas differences in yolk and shell traits were temporary and disappeared at later sampling points (P > 0.05). Overall, the results demonstrate that short fasting periods combined with recovery diets of varying CP levels effectively induce molt and support postmolt productivity in aged laying hens, providing a practical and welfare-oriented alternative to conventional molting programs.
Torki et al. (Sun,) studied this question.