Forced Rest Induced by Molt or Low-Salt Diet and Subsequent Hen Performance

Abstract

Four commercial strains of Single Comb White Leghorn hens were either force-molted by standard methods or force-rested by means of a low-salt diet (no added salt) at 66 weeks of age. After an 8-week molt/rest period, all hens were fed the same standard layer diet for an additional 28 weeks.During the resting period, egg production of the hens fed the low-salt diet declined gradually to a daily low of 13.0 percent after 38 days while the force-molted hens were completely out of production in 7 days.The low-salt treatment adversely affected postmolt hen-day and hen-house egg production, feed efficiency, egg shell thickness, and resulted in more broken eggs (P<.05) as compared to the force-molt treatment. Body weight gain, egg specific gravity, and egg weight were also depressed by the low-salt treatment, although not to a significant extent.The poorer postmolt performance of the hens fed the low-salt diet was believed related to a higher level of sodium in the diet (.13%) than had been calculated (.044%)