Desempenho e expressão gênica em codornas japonesas submetidas a restrição alimentar pós-eclosão e suplementadas com glutamina e ácido glutâmico

Abstract

The effects of post-hatch feed restriction on performance and organ weight in female Japanese quails supplemented with glutamine and glutamic acid (Gln+Glu) were assessed. The birds were distributed according to a completely randomized design in a 3 x 2 factorial using three restriction periods (immediate access to food or delayed access for 24 or 48 h) and two Gln+Glu supplementation levels (0 or 1%). The weights related to the liver, gizzard, proventriculus, small intestine and large intestine and length of the small intestine at 35 days of age were considered. Live weight, feed intake, weight gain and feed conversion were evaluated from 1 to 35 days of age. Organ relative weights were determined at 35, performance was assessed from 1 to 35 days and relative jejunal gene expression of the nutrient transporters for neutral amino acids (B0AT and ASCT1) and for peptides (PEPT1) were determined at 7 and 14 d. At 35 days, the weight of the large intestine was greater in birds that received food restriction for 48 hours and in birds that received supplementation with Gln+Glu, while the length of the small intestine was affected in isolation by the diet; birds not supplemented with Gln+Glu had a longer small intestine. Gln+Glu supplementation had no separate effect on live weight, weight gain or feed conversion at 35d, by decreased feed intake. Delayed access to feed decreased B0AT expression at 7 and 14d in non-supplemented birds; whereas Gln+Glu supplementation was able to significantly upregulate B0AT expression at 7d in restricted birds, but not significantly at 14d. On the other hand, at 7 and 14d, restriction upregulated ASCT1 expression significantly in non-supplemented birds, and not significantly in Gln+Glu birds. PEPT1 increased in 7-d-old quails that had immediate access to food and were supplemented with Gln+Glu, but not in restricted birds. Quails should be supplemented with glutamine and glutamic acid if access to food will be delayed from hatching until housing to diminish the negative effects on performance, since supplementation potentially increase the ability to absorb these amino acids that can be used as energy sources by the intestinal mucosa.