Dietary glutamine-glutamate supplementation enhances growth performance and intestinal villi development in cage-farmed Nile tilapia fingerlings

Abstract

The objective of this research was to evaluate the effect of increasing levels of associated glutamine and glutamic acid on growth performance and intestinal development of Nile tilapia, Oreochromis niloticus, fingerlings. Five isoproteic (~344.70 g kg −1 crude protein) and isocaloric diets (~3,925 kcal kg −1 gross energy) were developed containing 0, 5, 10, 15, or 20 g kg −1 of associated glutamine and glutamic acid in extruded diets. Fish (n = 2,000, mean body weight of 2.12±0.53 g) were distributed into twenty 1-m 3 floating net cages in an entirely randomized design with five treatments and four replicates, and each replicate comprised one floating net cage with 100 fish. Fish were hand-fed seven days per week, three times a day until apparent satiety for 45 days. There was a quadratic effect on final body weight, body weight gain, daily weight gain, feed conversion ratio, protein retention efficiency, net protein utilization, and intestinal villi height with optimized values for supplementation of associated glutamine and glutamic acid at 10.

Dietary γ-Aminobutyric Acid (GABA) Promotes Growth and Resistance to Vibrio alginolyticus in Whiteleg Shrimp Litopenaeus vannamei

“…In our study, no significant differences were observed in the whole-body composition analysis of whiteleg shrimp fed diets with different levels of GABA. It was previously shown that dietary glutamine and glutamate, which are precursors of GABA, did not influence whole-body proximate composition of Nile tilapia [53]. Also, the body composition of juvenile grass carp was not influenced by the addition of dietary gamma-aminobutyric acid in the diet [32].…”