Effects of Dietary Boric Acid Supplementation on Performance, Eggshell Quality and Some Serum Parameters in Aged Laying Hens

The effects of dietary boric acid (BA) supplementation on feed consumption, feed efficiency, egg production, egg weight, eggshell thickness, eggshell breaking strength, and some serum parameters (Ca, P, and Mg) were examined in 100 layer hens at 60 weeks of age. Commercial corn-soy-based layer diets were formulated as basal diets for the control treatment. Basal diets were supplemented with 25, 50, and 100 mg/kg BA (H3BO3), respectively, in experimental groups I, II, and III. In total, 4 dietary treatments were employed in the experiment. The experiment lasted 75 days. Feed efficiency and egg production values were not affected significantly by dietary treatments during the experiment (P > 0.05). However, layer hens that received diets supplemented with BA had better feed consumption, egg weight, percentage of cracked eggs, and egg shell quality (eggshell thickness, eggshell breaking strength) than the control group. Additionally, serum Mg levels were significantly (P < 0.01) increased by BA supplementation. It was concluded that dietary boron supplementation has positive effects on mineral balance, and therefore reduces the percentage of cracked eggs by improving eggshell thickness and egg shell breaking strength in aged laying hens.