Physiological and Histological Responses of Broiler Chicks to in ovo Injection with Folic Acid or L-Carnitine During Embryogenesis

Abstract

The aim of the present study was to evaluate the effect of in ovo injection with folic acid or L-Carnitine (L-Car) on performance, some blood biochemical and muscles traits of posthatch chicks. Eggs were obtained from broiler breeder stock and divided into four similar groups at 14 day of incubation. The 1st group received no treatment (negative control) while the 2nd was subjected to in ovo injection of 0.1 ml distilled water/ egg as solvent (S) into the air cell (positive control). The third one was given in ovo folic acid at a concentration of 1 mg / egg and the fourth group was in ovo injected with 1mg / egg of L- Car. The present findings revealed that chicks hatched from eggs treated with folic acid or L-Car has significantly better productive performance (higher LBW, BWG and better FCR) compared with untreated one. Body fat% and intramuscular fat% (on dry matter basis) were significantly reduced with treatments, especially for L- Car. Broiler chicks whose eggs were treated with folic acid or L-Car had lower plasma concentration of total lipid, cholesterol, triglycerides and LDL. Both treatments elevated LDH activity and plasma levels of T3, T4 and IGF-I at 6 weeks of age. Folic acid and L-Car induce myocytes hypertrophy which in turn enhances carcass % and breast muscle yield.