Methionine Supplementation of Maternal Diet Improves Hatching Traits, Initial Development, and Performance in Japanese Quail Fed Different Levels of Methionine During Growth

This study examined the effects of dietary levels of methionine on lipid and intestinal metabolism in Japanese quail hens and their progeny. The experiment was conducted according to a 3 × 3 factorial design, with three maternal and three progeny diets, as follows: low-methionine (LMET), recommended methionine (MET), and high-methionine (HMET). Methionine supplementation improved reproductive performance during laying (p < 0.05). Intestinal morphometry revealed that MET and HMET diets increased duodenal villus width and crypt depth in hens (p < 0.05). Hens fed the HMET diet showed higher expression of amino acid transport and barrier function genes. Hens fed LMET produced offspring with lower body weight at 15 days of age and lower weight gain (1–15 days of age) than hens fed MET and HMET (p = 0.0002). During the grower phase, chicks fed LMET diet had lower body weight at 15 (p < 0.0001) and 35 (p < 0.0001) days and worse feed conversion ratio (p = 0.0006) than chicks fed MET and HMET. Progeny from MET or HMET hens had improved intestinal histomorphometry. Overall, methionine supplementation of quail diets enhances intestinal function and reproductive performance in hens, improving chick performance in the starter and grower phases.