Effects of dietary copper supplementation on performance, egg quality parameters, yolk cholesterol and fatty acid profiles in laying hens

The present study envisaged the effects of different levels of dietary copper supplementation on performance, egg quality parameters, serum and yolk cholesterol and triglyceride levels, and yolk fatty acid profile in laying hens. Total 96 Lohman laying hens (38 weeks old) were randomly divided into four groups (n=24 each). Experimental diets were prepared by adding copper (0, 200, 250 or 300 mg/kg) to basal diet and feeding was lasted 12 weeks. Dietary copper supplementation decreased egg weight and feed intake but did not affect other performance parameters compared to the control diet. Shape index, shell weight, shell thickness, yolk color, yolk index, albumen index, and haugh unit were not influenced by dietary copper supplementation, whereas shell strength increased due to the inclusion of copper in the basal diet. Copper supplementation did not affect the fatty acid profile of the egg yolk. The yolk cholesterol ratio decreased by 7.22% in the presence of 250 mg/kg copper supplementation compared to control diet. Therefore, high levels of dietary copper supplementation in the diet of laying hens can be beneficial for improving shell strength and reducing the cholesterol content of the yolk.