Laying Hen Performance and Yolk Iodine, Cobalt and Iron Content Increased by Dietary Supplementation of Potassium Iodide, Vitamin B12 and Ferrous Sulfate

Abstract

In this experiment, 320 laying hens of HyLine W-36 strain were used in a 2 🞩 2 🞩 2 factorial arrangement with 8 treatments with 8 birds in each pen,including 0 and 400 mg.kg of iron salt (Fe), 0 and 450 mg.kg of iodide (I) and 0 and 0.1 mg.kg of vitamin B12 in 5 replicates and replicate in from 26 to 39 weeks in a completely randomized design. Dietary experiments had significant effects on the performance of laying hens at the end of the experiment period (P < 0:05). The use of I, B12 and Fe salts had significant effects on the content of these microelements of egg yolks in the main effects and interactions (P < 0:05). In the interaction of Fe and I, the use of 450 mg.kg of I and 0 level of Fe increased the I content of egg yolks (P < 0:05). In 400 mg.kg of Fe combined with I, or the use of 400 mg.kg of Fe with 0 level of iodine salt caused a sharp decrease in the I content of eggs (P < 0:05). Supplementation of laying diets with Fe and I had no significant effects on egg yolk content of Fe and Cobalt (Co) (P > 0:05). However, I content in yolk was significantly reduced (P < 0:05). In the interaction of treatments containing Fe and vitamin B12, the lowest amount of Co and the highest level of I were observed at the 0 level of both of these supplements (P < 0:05) whereas, the combined use of Fe and vitamin B12 increased the level of cobalt and decreased the iodine content of eggs (P < 0:05). Interactions of I and vitamin B12 showed the lowest levels of I and cobalt at 0 levels of these two salts in hens' diets, while the combined use of these salts increased the iron, cobalt and iodine content of eggs (P < 0:05). In the three-way effects between these salts, iron content, cobalt of eggs increased and the highest amount of iodine was observed in the third treatments which contained iodine without vitamin B12 and iron (P < 0:05). Treatments had no significant effects on cobalt content of eggs (P < 0:05). Overall results showed that the use of iron, iodine, and vitamin B12 salt supplements has improved the performance of hens, as well as the egg content, including iron, iodine, and cobalt, and improved some of the economic characteristics of hens.