The relevance of functional amino acids to support the health of growing pigs

On commercial farms, young growing pigs are frequently affected by health problems from multifactorial origins (e.g. environmental changes, biosecurity, management, and feed) that result in inflammation and activation of body defenses. Inflammation states alter animal metabolism in such a way that nutrients (particularly amino acids) are diverted from the use for growth towards the production of defense-related proteins and low-molecular-weight compounds (e.g., nitric oxide, H2S, and glutathione) for supporting the activity of rapidly dividing cells such as immune cells and enterocytes. Furthermore, amino acids may act specifically as signaling molecules to regulate metabolic pathways during inflammation. Thus, new knowledge on the specific role and metabolism of each amino acid is needed to refine nutritional recommendations for pigs of different phenotypes and genotypes, with the objective of maintaining animal health and performance under sub-optimal rearing conditions. This paper aims at summarizing recent advances in research on the functional roles of amino acids related to swine health. Specifically, the review highlights current knowledge on the impact of inflammation on the intake and metabolism of amino acids; their relevance for the physical gut mucosal barrier and antioxidant defense, as well as their roles in the syntheses of defense molecules and in the regulation of immune response. Practical implications for feeding strategies adapted to various health conditions of growing pigs are also discussed along with our general perspectives on related research

Glutamine and cystine-enriched diets modulate aquaporins gene expression in the small intestine of piglets

Research Areas: Science & Technology ; Other TopicsABSTRACT - The regulation of glycerol permeability in the gastrointestinal tract is crucial to control fat deposition, lipolysis and gluconeogenesis. Knowing that the amino acid glutamine is a physiological regulator of gluconeogenesis, whereas cystine promotes adiposity, herein we investigated the effects of dietary supplementation with glutamine and cystine on the serum biochemical parameters of piglets fed on amino acid-enriched diets, as well as on the transcriptional profile of membrane water and glycerol channels aquaporins (AQPs) in the ileum portion of the small intestine and its impact on intestinal permeability. Twenty male piglets with an initial body weight of 8.8 ± 0.89 kg were allocated to four dietary treatments (n = 5) and received, during a four week-period, a basal diet without supplementation (control) or supplemented with 8 kg/ton of glutamine (Gln), cystine (Cys) or the combination of the two amino acids in equal proportions (Gln + Cys). Most biochemical parameters were found improved in piglets fed Gln and Cys diet. mRNA levels of AQP3 were found predominant over the others. Both amino acids, individually or combined, were responsible for a consistent downregulation of AQP1, AQP7 and AQP10, without impacting on water permeability. Conversely, Cys enriched diet upregulated AQP3 enhancing basolateral membranes glycerol permeability and downregulating glycerol kinase (GK) of intestinal cells. Altogether, our data reveal that amino acids dietary supplementation can modulate intestinal AQPs expression and unveil AQP3 as a promising target for adipogenesis regulation.info:eu-repo/semantics/publishedVersio

Influence du croisement génétique sur le métabolisme postprandial du tryptophane chez le porc

National audienceTryptophan (Trp), an indispensable amino acid, is involved in numerous metabolic pathways. Previous data showed that Trp conversion into kynurenine and nicotinamide may differ among studies and such differences cannot be explained by different dietary niacin supply. We hypothesized that pig genotype influences Trp metabolism and thus the conversion of Trp into metabolites. The objective of this study was to compare plasma appearance of Trp and related metabolites in 12 Duroc and 12 Piétrain crossbred growing pigs after a meal test. Pigs were fitted with a catheter in the jugular vein to perform frequent blood samplings. Within each genotype, 6 pigs were fed a limiting or non‐limiting Trp diet (15 and 22% Trp:Lys DIS, respectively). After an overnight fasting, 350 g of the experimental diets was offered to each pig and plasma concentrations of Trp, kynurenine, nicotinamide and serotonine were measured for 6 hours. The activities of Trp degrading enzymes were measured in different tissues collected after pig slaughtering. Our data showed an increase in plasma concentrations of Trp and its metabolites after the meal and with the Trp dietary content. However, plasma concentrations of Trp metabolites and enzyme activities were not significantly different between Duroc and Piétrain crossbred

Influence du croisement génétique sur le métabolisme postprandial du tryptophane chez le porc

Tryptophan (Trp), an indispensable amino acid, is involved in numerous metabolic pathways. Previous data showed that Trp conversion into kynurenine and nicotinamide may differ among studies and such differences cannot be explained by different dietary niacin supply. We hypothesized that pig genotype influences Trp metabolism and thus the conversion of Trp into metabolites. The objective of this study was to compare plasma appearance of Trp and related metabolites in 12 Duroc and 12 Piétrain crossbred growing pigs after a meal test. Pigs were fitted with a catheter in the jugular vein to perform frequent blood samplings. Within each genotype, 6 pigs were fed a limiting or non‐limiting Trp diet (15 and 22% Trp:Lys DIS, respectively). After an overnight fasting, 350 g of the experimental diets was offered to each pig and plasma concentrations of Trp, kynurenine, nicotinamide and serotonine were measured for 6 hours. The activities of Trp degrading enzymes were measured in different tissues collected after pig slaughtering. Our data showed an increase in plasma concentrations of Trp and its metabolites after the meal and with the Trp dietary content. However, plasma concentrations of Trp metabolites and enzyme activities were not significantly different between Duroc and Piétrain crossbred

Détermination par méta-analyse du besoin en tryptophane pour les porcelets

National audienc

Tryptophan metabolism, growth responses, and postprandial insulin metabolism in weaned piglets according to the dietary provision of niacin (vitamin B) and tryptophan

International audienceThe present experiment aimed to determine if Trp metabolism and growth responses to dietary Trp are modulated by dietary niacin (B) in weanling piglets. Piglets weaned at 3 wk of age were distributed 1 wk later (7.6 kg of BW, SEM = 0.1) in 52 pens of 2 animals each. Pens were assigned to factorial dietary treatments with 2 additions of B, 15 mg/kg (LB3) vs. 45 mg/kg (HB3) and 2 additions of Trp, 0 mg/kg (-Trp) vs. 1 mg/kg (+Trp) for Trp to Lys ratios of 0.16 vs. 0.24, respectively. Growth performance was recorded every week from 4 to 10 wk of age. Fasting blood samples were taken at 4, 6, 8, and 10 wk of age. From 4 to 10 wk of age, ADFI tended to be greater ( = 0.10) in HB3 than in LB3 (1,031 vs. 1,003 g, SEM = 7), and this was reflected ( = 0.06) by ADG (642 vs. 623 g, SEM = 7). No treatment effect was observed on plasma Trp or kynurenine (Kyn), an intermediate metabolite of Trp catabolism. The response of plasma nicotinamide (Nam), a product of Trp catabolism and an indicator of B status, to dietary B differed according to treatments (interaction Trp × B, < 0.01) with values of 1.4, 3.3, 4.1, and 5.3 μM (SEM = 0.1) in LB3-Trp, HB3-Trp, LB3+Trp, and HB3+Trp, respectively. At 11 wk of age, postprandial blood samples were collected from 6 piglets per treatment for measurements of Trp and insulin metabolism. Postprandial plasma Trp (96.4 vs. 72.2 μ, SEM = 3.4) and Kyn (1.7 vs. 1.3 μ, SEM = 0.1) were greater ( < 0.01) in +Trp vs. -Trp. Postprandial plasma Nam was greater ( < 0.01) in +Trp vs. -Trp (3.4 vs. 1.9 µ, SEM = 0.3) and in HB3 vs. LB3 piglets (3.4 vs. 1.9 µ, SEM = 0.3). Postprandial peaks and areas under curves of C-peptide and glucose were not affected by treatments. However, for insulin, the postprandial peak was lower in +Trp vs. -Trp piglets in the LB3 group (interaction Trp × B, < 0.05); values were 1.3, 1.0, 0.7, and 1.0 n (SEM = 0.1) in LB3-Trp, HB3-Trp, LB3+Trp, and HB3+Trp, respectively. The peak value of the molar ratio insulin:C-peptide was lower ( < 0.02) in +Trp vs. -Trp piglets (0.56 vs. 0.73, SEM = 0.05). The responses observed on growth performance and plasma Nam suggest that the LB3 level was suboptimal. According also to plasma Nam, it appears that supplemental dietary B can attenuate Trp oxidation toward niacin metabolites. Postprandial profiles of insulin and C-peptide indicate that Trp action is exerted on insulin clearance rather than on insulin secretion in piglets, without apparent consequences on glucose utilization

Amino acid requirements in piglets with special emphasis on tryptophan and valine

International audienc

Le besoin en tryptophane des porcs charcutiers

Session : AlimentationSession : AlimentationA meta‐analysis was performed to estimate the tryptophan to lysine requirement ratio, on a standardized ileal digestible basis (SIDTrp:Lys),that maximises average daily gain (ADG), average daily feed intake (ADFI) and gain to feed ratio (G:F) of pigs between 25 and 120kg body weight. A database of87trials was established. The nutrient composition of diets was recalculated from feed ingredients and information from INRA tables. Among the trials, 13weredesigned to express the requirement relative to Lys (i.e., Lys was the second limiting factor after Trp) while testing at least four levels of Trp, and these trials were considered in the metaanalysis. The curvilinear‐plateau model was used to estimate the animal response to SID Trp:Lys. The estimated SID Trp:Lys requirements were20.9, 19.9 and 21.0%, for ADG, ADFI and G:F, respectively, with an average value of 20.6%. The response between 17 and 21% SID Trp:Lys levels was estimated to be +6.7 and +3.6%, for ADG and G:F, respectively