Influence of In Ovo Leptin Injection into Yolk Sac on Embryo Development, Blood Biochemical Parameters and Lipid Metabolism of Broiler Chicks during Early Post-Hatching Period

The study aimed to investigate the effect of in ovo (IO) leptin injection on yolk sac concentration, embryo development, blood lipid metabolism, and biochemical parameters broiler chicks during early post-hatching period. Hatching eggs were weighed placed an incubator with 100 eggs/4 replications/group. groups were: non-injected group (C); 3 injected μl phosphate buffer solution (PBS); 0.5 (L0.5), 1 (L1) PBS. Pure hormone dissolved PBS was into day 7 incubation. Yolk/yolk concentrations at onset incubation, days 15 hatching determined. Embryo/chick development determined all ages. Serum leptin, tri-iodothyronine (T3), thyroxine (T4), creatine kinase, total protein, uric acid, profiles measured chick age. level similar hatching. Leptin a higher 7th than other IO injection* age significant for serum level, which one-day L0.5 T3, T4, profiles, embryo/chick did not change leptin. HDL C application affects metabolism depending dose male post-hatch period, without affecting development.Leptin development.