| This experiment was conducted to study the effect of early feeding by injection embryos of cobb-500 broiler breed with different levels of ascorbic acid (AA) at 17.5 day of incubation and applying feed inside hatching machine immediately after hatching on final productive performance and some blood traits. Three hundred hatching eggs collected from breeders, 29 weeks old were individually weighed and incubated. On 17.5 day of incubation eggs were divided into six equal groups (50 eggs each), then injected according to the following treatment groups; first treatment (T1) without injection (negative control), second treatment (T2) 0.5 ml sterilized distilled water, third treatment (T3) without injection, hatched chicks were immediately fed inside hatching machine, fourth treatment (T4) 0.5 ml of 0.2 % AA, fifth treatment (T5) 0.5 ml of 0.6 % AA, sixth treatment (T6) 0.5 of 1.0 % AA. Hatched chicks were transferred, allocated into pens. Each group was consisted of 3 replicates (pens), 12 birds each. Birds were fed on starter and finisher diets along 5 weeks. Feed and water were available ad libitum. Results revealed that final weight gain (WG) and final feed consumption (FC) were increased significantly in T5 and T1 respectively. A significant improvement was found in feed conversion ratio (FCR) and mortality (M) in T3, T4, T5 and T6. No significant differences was noticed among all treatment groups in the percentage of WG (except T2) and FC, whereas the percentage of FCR and M was improved in T3, T4, T5 and T6. An increase was found in white blood cells, red blood cells, hemoglobin and packed cell volume of T3, T4, T5 and T6. It is concluded that in ovo injection with AA, particularly 0.6 % (T5) and feeding inside hatching machine improved studied productive and blood traits. |