PSIII-A-3 - An Investigation of the Effect of Folic Acid and Its Delivery Routes on Broiler Chickens’ Hatch and Growth Performance, Blood Biochemistry, and Antioxidant Status

Abstract: This study investigated the effect of folic acid (FA) and its delivery routes (in-feed or in ovo) on broiler chicken’s hatch and growth performance, blood biochemistry, and antioxidant status. A total of 1,860 Cobb 500 hatching eggs were incubated for 21 days. On d 12 of incubation, viable eggs were randomly allotted to 3 groups: the non-injected group, in ovo folic acid 1 (FA1), and in ovo folic acid 2 groups (FA2) and subsequently injected with 0.1 ml FA containing 0.1 mg and 0.15 mg/egg, via the amnion, respectively. At hatch, chicks were re-allotted to 5 new treatment groups: FA1, FA2, in-feed folic acid (FA3; 5mg/kg), in-feed bacitracin methylene disalicylate (BMD; 55 mg/kg), and negative control (NC; corn-wheat-soybean diet) in 6 replicate pens (22 birds/pen) and raised in starter (d 0 -14), grower (d 15-24) and finisher (d 25-35) phases. Hatch parameters were assessed on d 0, and body weight and feed intake (FI) were determined weekly. On d 25, 1 bird/cage was euthanized, and immune organs weighed. Blood samples were collected for biochemistry and antioxidant (Superoxide dismutase-SOD and Malondialdehyde-MDA) analysis. Data were analyzed in a randomized complete block design. While FA1 and FA2 decreased (P< 0.001) hatchability in a dose-dependent manner, FA2 caused a 2% increase (P< 0.05) in average chick weight compared to the non-injected group. Compared to the BMD treatment, FA3 decreased (P< 0.05) average FI across all feeding phases. However, only in the grower phase did BMD treatment record a lower (P< 0.05) feed conversion ratio (FCR) compared to the NC treatment. Other treatments recorded intermediate FCR values. FA1 and FA2 recorded a tendency (P< 0.1) to increase MDA levels and SOD activity by 50% and 19%, respectively, compared to the NC treatment. Besides its negative effect on hatchability, FA2 may help improve embryonic development and antioxidant status in broiler chickens.