This study investigated whether dietary vitamin E (VE) supplementation could alleviate any detrimental effects of ageing corn in the diet for laying hens on egg performance, egg quality, serum biochemical parameters, cholesterol content and the fatty acid (FA) profile of egg yolks. The experiment consisted of a 2 × 3 factorial design with two corn types (normal corn and ageing corn) and three concentrations of VE (0, 20 and 100 IU/kg). A total of 216 Lohmann laying hens (50‐week‐old) were randomly allocated into six treatment diets for 12 week. Each treatment had six replicates with six hens. The results showed that ageing corn significantly reduced average daily feed intake (ADFI; p < 0.01) and egg weight (p < 0.05). Dietary VE supplementation had no significant influences on egg production performance (p > 0.05). Egg yolk colour was decreased in ageing corn diets (p < 0.01), while 20 and 100 IU/kg VE significantly improved vitelline membrane strength (p < 0.01) compared with feeding of 0 IU/kg VE. Ageing corn also significantly decreased the content of cholesterol including total cholesterol (TC; p < 0.05), low density lipoprotein cholesterol (LDL‐C; p < 0.01) and very low density lipoprotein cholesterol (VLDL‐C; p < 0.05) in the serum. Feeding 100 IU/kg VE significantly increased the content of LDL‐C (p < 0.01) and VLDL‐C (p < 0.05) in the serum. Furthermore, the content of the oleic acid, docosahexaenoic acid and total monounsaturated fatty acid (MUFA) was lower (p < 0.05) and stearic acid and total saturated fatty acid (SFA) was higher (p < 0.05) in egg yolks in ageing corn diets. Ageing corn resulted in reduced feed intake, egg weights and yolk colour, but the effects of VE supplementation were independent of those of age of corn and were unable to counteract the negative effects of feeding ageing corn.

Objective: The objective of this study was to determine whether a dietary vitamin E (VE) supplement could alleviate any detrimental effects of aged corn on lipid metabolism and antioxidant status in laying hens.Methods: The experiment consisted of a 2×3 factorial design with two corn types (normal corn and aged corn (stored for 4 yr) and three concentrations of VE (0, 20, and 100 IU/kg). A total of 216 Lohmann laying hens (50 wk of age) were randomly allocated into six treatment diets for 12 wk. Each treatment had 6 replicates of 6 hens per replicate.Results: The results show that aged corn significantly decreased the content of low-density lipoprotein cholesterol (p<0.05), and reduced chemokine-like receptor 1 (CMKLR1) mRNA expression (p<0.05) in the liver compared to controls. Diet with VE did not alter the content of crude fat and cholesterol (p>0.05), or acetyl-CoA carboxylase, lipoprotein lipase, fatty acid synthase or CMKLR1 mRNA expression (p>0.05) in the liver among treatment groups. Aged corn significantly increased the content of malondialdehyde (MDA) (p<0.05) and decreased superoxide dismutase (SOD) activity (p<0.05) in the liver. The VE increased the content of MDA (p<0.05) but decreased glutathione peroxidase (GSH-Px) activity in serum (p<0.01) and in the ovaries (p<0.05). Adding VE at 20 and 100 IU/kg significantly increased GSH-Px activity (p<0.05) in liver and in serum (p<0.01), 100 IU/kg VE significantly increased SOD activity (p<0.05) in serum. Aged corn had no significant effects on <i>GSH-Px</i> mRNA or <i>SOD</i> mRNA expression (p<0.01) in the liver and ovaries. Addition of 100 IU/kg VE could significantly increase <i>SOD</i> mRNA expression (p<0.01) in the liver and ovary.Conclusion: Aged corn affected lipid metabolism and decreased the antioxidant function of laying hens. Dietary VE supplementation was unable to counteract the negative effects of aged corn on lipid metabolism. However, addition of 100 IU/kg VE prevented aged corninduced lipid peroxidation in the organs of laying hens.

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