Abstract
Authors reported previously on the effect of forced molting induced in spring on the layers. This paper deals with the performance of the laying hens following the forced molting which was induced in autumn.
One hundred twenty commercial laying hens (DeKalb 151) which laid eggs for longer than one year, divided into three groups. In Group 1 and 2, the birds were deprived of both feed and water for 3 days and of feed for succeeding 2 days. The birds in Group 3 were fed ad libitum. The experiment was conducted from October 18, 1967 to the end of October 1968. All birds recieved normal daylight before the start of this experiment. In Group 1 daylength was supplemented with incandescent lamp to give a 14 hours per day at the beginning of the experiment and to increase lighting 15 minutes per week to reach 17 hours of light per day. The birds in Group 2 and 3 were recieved supplemented light to give 15 hours light per day. Egg production, egg weight and feed conversion were recorded, egg quality also checked.
1) Eggs laid within 48 hours after depriving of feed and water were normal, but after 48 hours thin shell eggs and soft shell eggs were laid. The bird stopped laying within 96 hours. Many birds showed severe feathering from 10 to 15 days after deprivation. Most of birds treated recovered egg production before all primary flight feathers did not fall down.
2) No significant difference between Group 1 and 2 was observed in nonlaying days following treatment. Higher egg production in one year after treatment was recorded in treated groups than in control. A significant difference in egg production was observed between Group 2 and 3.
3) There were little differences in feed intake, egg weight and viability among the groups. In height of egg yolk and white (Haugh units), significant differences were observed between the treated groups and control.
