EFFECT OF IODINE SOURCES AND DIETARY ENERGY LEVELS ON PRODUCTIVE, PHYSIOLOGICAL AND IMMUNOLOGICAL PERFORMANCE OF BANDARAH LAYING HENS

A total number of 330 Bandarah chicken (300 females and 30 males) 40-wks-old, were randomly distributed equally into six experimental groups to investigate the effect of supplementing iodine sources (organic and inorganic) with different metabolizable energy levels in 2×3 factorial design on productive, reproductive and immunological traits during the laying period (40-56 wks of age). Laying hens were fed three different metabolizable energy levels being 2606, 2705 and 2803 kcal/kg diet with 0.5 mg iodine from two sources, organic (iodine enriched yeast) and inorganic (Ca (IO3)2∙H2O). Results obtained could be summarized as follow: Chickens fed diet containing 2705 kcal of ME /Kg diet and supplemented with organic iodine recorded significantly the highest laying rate and egg mass and the best feed conversation ratio compared with the other experimental groups. The highest ratio of triiodothyronine to thyroxin were recorded for the groups fed diet containing 2606 or 2705 kcal of ME /Kg diet and supplied with organic iodine compared with the other experimental groups. The group fed diet contained 2606 kcal of ME /Kg diet and supplied with organic iodine had significantly an increase in plasma high density lipoprotein and high density lipoprotein to low density lipoprotein ratio compared with the other experimental groups. Results displayed that there was a significant increase in serum total antioxidant capacity when hens fed diet contained 2606 kcal of ME /Kg diet compared with those fed 2705 or 2803 kcal of ME /Kg diet supplemented with both of iodine sources. Feeding laying hen diet containing 2606 kcal of ME /Kg diet supplied with organic iodine showed significantly the highest Immunoglobulin G value compared with the others.  It could be concluded that the supplementing diets containing 2705 or 2606 kcal of ME /Kg diet with 0.5 mg iodine enriched yeast/Kg diet is the most successful supplement for enhancing productive, hatchability, immunity, antioxidant status, as well as economical efficiency for Bandarah laying hens.