Studies on production performance of layers supplemented with dietary melatonin

Twenty four layer birds of 24 weeks were randomly assigned to three groups of eight birds in each. Melatonin was added to feed @ 2mg./Kg (M-I) and 8mg./Kg.(M-II) for the period of 3 weeks. Third group was left unsupplemented as control. The birds were raised on continuous lighting, feed and water was available ad lib. Heperinized blood was collected from all the groups at the end of third week for hematological and biochemical profiles. Similarly eggs were also collected to analyze the parameters viz. egg weight, egg volume, albumin and yolk volume, egg shell weight and thickness. Melatonin supplementation in layer birds resulted in increase in egg parameters except egg production, which was decreased significantly in both the supplemented groups. Only slight variations were observed in hematological parameters with an increase in hemoglobin percentage, number of heterophils, basophils, monocytes and decrease in packed cell volume, total erythrocyte count and eosinophils count. The level of blood glucose and total protein increased significantly in the group M-I as compared to M-II and control groups. In contrary, declining trend was observed in the levels of calcium and phosphorus in both the supplemented groups. It may be concluded that melatonin supplementation at 2.0 mg/kg feed improves the egg weight, egg volume, albumen and yolk volume, egg shell weight and thickness. The level of blood glucose and total protein increased significantly in treated groups.