Egg Production and Biological Activities in Laying Hens are Affected By Different Molting Programs

Abstract

This study was conducted to compare two molting methods by using aluminum sulfate (2.5 g/kg) and diet withdrawal on productivity, eggs quality, and lipid profile of laying hens. A total of 180 Hy-line Brown hens 80 weeks of age were randomly assigned to three replicates of three treatments of 30 hens/treatment from 70–87 weeks of age; hens were exposed to one of the following two molt groups: T1, aluminum sulfate (2.5 g/kg) and T2, feed withdrawal(14 days). Egg production was recorded daily/hen in each cage and weekly for each treatment. Following the forced molting, feed consumption was recorded and calculated weekly. Feed conversion rate as a feed/g egg mass was calculated weekly for each treatment. Haugh unit was determined by [11]. At the end of the experiment blood samples were collected from nine laying hens/treatment from the extrinsic vein using a 5mL sterilized syringe with heparin for biochemical determination parameters. Blood samples were centrifuged at 4000rpm for ten minutes. Plasma and serum were separated and stored (- 20°C) until the biochemical measurement. Cholesterol, Triglycerides, Total Protein, Albumin, Globulin, ALT, and AST were determined in this study. The data were analyzed using (ANOVA) to analyze the difference between treatments. A significant difference was identified between treatments, by using Duncan’s test for multiple comparisons. The results of this study indicated that hens subject to feed withdrawal treatment showed a significant (p < 0.05) percentage of body weight loss compared to those in the feed with aluminum (2.5g/kg). We did not find significant (p>0.05) differences in hens performance for all treatments in the post molt for 56 days. Our data showed hens had significantly lower (p < 0.05) in hen day egg production when compared with other treatments after molting, also, the egg weight showed no significant differences between treatments. The results showed a significant (p<0.05) difference in albumin and globulin between molt methods. Our experiment indicated that aluminum sulfate (2.5 g/kg) and feed withdrawal represent a viable alternative to the molting method for the successful induction of molting and retention of post molt performance.