Maternal dietary energy levels affected the lipid deposition of offspring embryos at the end of the laying period of broiler breeder hens

An experiment was conducted to evaluate the embryonic lipid deposition in yolk, embryo serum and tissues during the late laying period of Arbor Acres broiler breeder hens fed diets (21–60 weeks) with different levels of ME, 2.80 Mcal/kg (ND), 2.24 Mcal/kg (LD20) and 1.96 Mcal/kg (LD30) in a completely randomised experimental design. At 60 weeks of age, 100 fertile eggs in each group were collected and hatched. The results showed that low dietary energy decreased egg weight and egg content weight significantly, and embryo weight in LD20 was highest. Serum cholesterol level in LD20 (on each embryonic day) was significantly higher than those in other two groups. As the dietary energy level decreased, serum triglycerides level was decreased significantly, and serum low-density lipoprotein-cholesterol level was increased significantly. Serum high-density lipoprotein-cholesterol level was higher in LD30 than in other two groups on embryonic days 13, 15, 17 and 19, but higher in LD20 on embryonic day 21. In LD20, cholesterol level in the breast muscle and liver tissues and crude fat content in the breast muscle tissues were significantly higher than those in other two groups. LD30 got a lower cholesterol level in the thigh muscle tissues than ND. These results indicate that maternal dietary energy restriction directly affected lipid metabolism in embryos at the end of the laying period.