Suplementação de metionina na dieta materna e a modulação do metabolismo da progênie de codornas de postura

Abstract

Methionine in poultry diet does not only contribute to protein synthesis but can also influence the lipid metabolism, essential for egg production. In addition, it can improve the development and functioning of the intestinal environment, and thus nutrient uptake. This study evaluated how different levels of methionine supplementation can affect the lipid and intestinal metabolism of both the quail hen and her chicks. To this end, an experiment with a completely randomized 3 x 3 factorial design tested three diets for quail hens: diet without methionine supplementation (LMET); diet supplemented with the recommended level of methionine (MET); and diet with supplementation above the recommended level of methionine (HMET), and for each treatment of the mother hens, their chick were fed the same three diets: LMET; MET; and HMET. The expression of the following genes was evaluated: acetylCoAcarboxylase (ACC), fatty acid synthase (FAS), apolipoprotein A 1 (APOA1), apolipoprotein B (APOB), glucose transporter (SLC2A2), sodium-dependent glucose cotransporter (SLC5A1), sodium-dependent neutral amino acid transporter (SLC6A19), Y+L 1 amino acid transporter (SLC7A7), occludin (OCLN) and intestinal morphometry of both hen and chick. The methionine-supplemented diet contributed to a better reproductive performance during the laying period of the hens, since hens fed with such a diet laid heavier eggs, at higher rates of egg laying and hatching. The processes of laying and consequently, yolk and egg formation, are greatly influenced by lipid synthesis. Methionine supplementation also decreased the expression of the ACC and FAS genes. In addition, the maternal diet influenced the expression of APOA1 in the chick liver. In quails fed with MET, which were offspring of hens also fed with MET, the APOA1 gene was expressed at higher levels. Regarding intestinal morphometry, methionine supplementation increased the duodenum villi width and duodenum and jejunum crypt depth of the hens. The effect of the maternal diet, mainly of HMET, improved the morphological parameters of the chicks. When the chicks were also fed HMET, the results in relation to the morphology of the duodenum, jejunum and ileus of the Japanese quails were even better. The expression of SLC6A19 and SLC7A7 was highest in the duodenum of hens fed with HMET. When chicks from hens that received a methionine-supplemented diet were fed with MET, the expression of SLC2A2, SLC5A1 and OCLN genes increased. It was concluded that a methionine-supplemented diet (MET or HME), was essential to improve the reproductive parameters of the mother hen and the intestinal development process of the chick. In addition, a methionine-supplemented maternal diet optimized the phenotype expression of the offspring.