Nutrição inovo: Injeção de ácido fólico e aminoácidos sulfurados em ovos férteis de frangos de corte

Abstract

Folic acid (FA) and súlfur amino acids (AAS) such as methionine and cysteine are substances that participate in various metabolic processes in the animal, favoring tissue development and zootechnical performance. Thus, the objective was to determine the effect of in ovo injection of FA and AAS on the expression of myogenic genes, performance and carcass characteristics, organ weight and hematological and histological parameters of the small intestine and pectoral muscle of broiler chickens at hatch and in the productive phase. A total of 1200 eggs weighing 65± 0.74 g were divided into five experimental groups (240 eggs each): G1 - control group (intact eggs without inoculation); G2 - saline solution; G3 - 0.150 mg of AF; G4: 5.90 mg of L-methionine (Met 99%) + 3.40 mg of L-cysteine (cyst) and G5: AF (0.150 mg) + Met (5.90 mg) + Cistein (3.40 mg). In each injected egg, 0.5 ml of 75% NaCl was used as vehicle. After hatching, the chicks from each experimental group were housed in six boxes with 30 birds each, totaling 180 birds/group, which were kept until 42 of age. AF injection reduced (P < 0.05) feed conversion at 21 and 42 days of age, while AF + AAS increased (P < 0.05) the relative weight of lymphoid organs and ileum crypt depth at 21 days old. There were no differences (P>0.05) in hematological variables, muscle fiber area and carcass characteristics at day 1, 21° and 42° of age. Injection into fertile egg with folic acid (FA) increase the expression of PAX7 and MYF5 gene in the pectoral muscle in chicks and improve the feed conversion ratio of broilers at 42 days of age. The combination of AAS + AF benefit the relative weight of the spleen and thymus on the 21st day of life, as well as the depth of the ileum crypt on the 1st day. It is concluded that an inoculation of 0.15 mg/egg of AF on the first day of incubation can be used to improve gene expression and zootechnical performance of broiler chickens. The use of AAS at the doses tested should not be used at this age.