Dietary supplementation with glutamine or glutamic acid for weanling piglets

Abstract

The objective of this work was to evaluate the effects of dietary glutamine and glutamic acid supplementation on carbon turnover (δ13C) in the muscles of piglets, on animal performance, and on feed economic feasibility. The diets consisted of: control (C), 1% glutamine (G), and 1% glutamic acid (GA). In experiment I, 111 piglets were used to assess carbon turnover in the Masseter, Psoas major, and Abdominal internal oblique muscles in terms of their isotopic composition and 13C substitution over time. In experiment II, 72 piglets were assigned randomly to blocks (eight replicates per treatment and three animals per experimental unit), in order to evaluate animal performance and feed economic feasibility. The GA diet promoted the best 13C acceleration in the studied muscles. No diet effects were observed on performance variables. The G and GA diets presented higher costs than the C diet. Although supplementation with 1% glutamine or glutamic acid accelerates carbon turnover in the studied muscles, which suggests a faster recovery during post-weaning and proves the anabolic effect of these additives, its use is not economically viable for weanling piglets.

Review: The roles and functions of glutamine on intestinal health and performance of weaning pigs

“…In spite of the positive effects of glutamine on small intestinal villus morphology and plasma net xylose absorptive concentration in 28-day-old weaning pigs, 1% or 2% glutamine supplementation in a corn-soybean meal diet did not significantly affect growth performance during the 21-day treatment period (Hsu et al, 2010). Similar results were obtained by (Amorim et al, 2018) who also did not observe any significant effects of 1% glutamine or 1% glutamate on growth performance variables in pigs fed a rice grit and…”

“…Glutamine had the adverse effect of weaning on growth, villus height but not totally overcoming the stress of weaning on intestinal structure and function Wang et al (2014) 21 days old Mixtures of glutamine and glutamate (the ratio between glutamine and glutamate was unknown); five treatments: basal diet supplementation with 0, 0.5%, 1.0%, 1.5% mixtures and positive control (basal diet þ4% porcine plasma) for 21 days in corn and soybean meal-based diet soybean-based diet. Different diets, weaning age, experimental duration or dosage of glutamine may contribute to differing growth performance responses to glutamine or glutamate supplementation (Kitt et al, 2002;Di et al, 2003;Amorim et al, 2018).…”

Dietary Glutamic Acid Modulates Immune Responses and Gut Health of Weaned Pigs

“…Several studies reported that some feed additives, such as plant extracts, exogenous enzymes, and GLU, had beneficial effects on growth performance and gut barrier functions of pigs [ 8 , 14 , 15 , 28 ]. In particular, GLU is regarded as one of the most promising performance-enhancing additives with amino acid synthesis properties [ 8 ]. However, the correlations of dietary GLU on growth performance and intestinal barrier and immune functions of pigs are not fully understood.…”

“…These observations are in agreement with previous studies, suggesting that dietary GLU may give more beneficial effects on growth performance of weaned pigs around the first 10 to 21 days after weaning [ 9 , 29 , 30 ]. These results indicate that dietary GLU promotes the growth performance of pigs by increasing feed intake and performing as a metabolic fuel that more effectively increases cell turnover rate during intestinal development [ 8 , 9 ]. Moreover, it is well known that GLU has umami properties that may have an important role in the taste, palatability, and acceptability of the feeds [ 6 , 31 ].…”

“…Moreover, GLU is an important precursor for intestinal formation and immune system in the small intestine and can contribute to the immediate effect on nutrient absorption [ 7 ]. Previous studies reported that GLU improved the performance of weaned pigs [ 7 , 8 , 9 ]. The potential mechanisms of its action are as follows: (1) stimulation of oral and visceral sensory fibers [ 10 ], (2) an energy source to form the intestinal barrier structure and functions [ 11 ], and (3) regulation of intestinal nervous and immune systems as a signaling compound [ 12 ].…”