Effects of supplementation of graded level of glutamic acid to crude protein reduced diets on the performance of growing pigs.

A total of 150 growing pigs ([Landrace × Yorkshire] × Duroc) with an initial average body weight (BW) of 24.45 kg were used in a 6-week trial to estimate the optimum lysine to glutamic acid ratio in pigs fed low-protein diets supplemented with increasing level of synthetic glutamic acid (Glu). Pigs were randomly allotted to 5 dietary treatments consisting of either control diet (CON) formulated to have 157 g crude protein (CP) or negative control diets (NC, NC1, NC2 and NC3) with 20 g CP reduction and addition of Glu (1.1, 3.9, 6.8 and 9.6 g/kg feed respectively). Supplementing the increasing level of Glu to low CP diets did not exert any linear or quadratic responses in the growth performance parameters as well as nutrient digestibility. The serum creatinine concentration in pigs receiving CON diet showed trends (p = 0.063) in increment compared with pigs receiving NC diet. However, with the increase in the supplementation of Glu, there were no linear or quadratic responses on serum blood urea nitrogen (BUN) and creatinine concentrations. There was a tendency in the reduction (p = 0.088, p = 0.064) of backfat thickness and lean percentage, respectively, at week 3 and a trend in the reduction (p = 0.092) in lean percentage at week 6 in pigs fed NC diet compared with those fed CON diet. The increase in the supplemental level of Glu tended to show quadratic responses in the backfat thickness and lean percentage at week 3 and 6. In conclusion, the growth performance parameters as well as carcass traits with Lys: Glu ratio 1: 2.71 were very close with the mean values of CON diet indicating that 6.8 g Glu when supplemented to 2% CP reduced diet could achieve the comparable growth performance and carcass trait as that of standard basal diet.

The GH/IGF1 axis in the kidney of young goats fed a protein-reduced diet.

Feeding approaches for ruminants are changing to reduce N excretion as a major source of pollution. Based on the ruminohepatic cycle of N, it was assumed that the metabolism of ruminants could tolerate a reduced-protein diet well. However, metabolic changes such as a reduction in hepatic IGF1 mRNA expression, resulting in lower blood IGF1 levels due to decreased hepatic growth hormone receptor (GHR) expression, were found. Therefore, the aim of the present study was to determine the effect of a low-protein diet on the expression of GHR and subsequent IGF1 signalling in the renal cortex of young male goats to verify whether organ-specific synthesis of IGF1 mRNA expression occurs. Kidney cortex samples were obtained from eight goats fed a control diet (20% CP) and nine animals fed a reduced-protein diet (9% CP). The expression of GHR in the kidneys was reduced, whereas the expression of Janus kinase 2 (JAK2), suppressor of cytokine signalling 3 and signal transducers and activators of transcription 3 (STAT3) increased significantly. The stimulated JAK2 expression could modulate the expression of STAT3, which led to increased renal IGF1 mRNA expression. These results suggest that this increase in IGF1 mRNA expression in the kidneys is tissue-specific. This could be due to the autocrine/paracrine IGF1 effect on renal cell metabolism during a protein-reduced diet. These signalling pathways need further investigation to understand how and why low levels of protein stimulate IGF1 synthesis differently in the kidney than in the liver.

Economic Analysis of a Ketoanalogue-supplemented Very Low-protein Diet in Patients With Chronic Kidney Disease in Vietnam.

PURPOSE: The aim of this study was to estimate the cost-effectiveness of a very low-protein diet (VLPD) supplemented with ketoanalogues of essential amino acids compared with a conventional low-protein diet (LPD) in Vietnam. METHODS: The study was conducted from payer (base case), patient, and societal perspectives. A Markov model simulated costs and quality-adjusted life-years (QALYs) for patients with chronic kidney disease stage 4 or 5 (CKD4+) who were followed up during their lifetimes. Patients received a VLPD (0.3- to 0.4-g/kg/d diet) supplemented with ketoanalogues (5 kg/d [1 tablet]) versus LPD (0.6 g/kg/d, mixed proteins). In each model cycle, patient transitions among the health states-CKD4+ (nondialysis), dialysis, and death-were based on transition probabilities taken from the published literature. The time horizon covered the cohort's lifetime. Utilities and costs were estimated from literature review and projected for the lifespan considered in the model. Probabilistic and deterministic sensitivity analyses were performed. FINDINGS: The ketoanalogue-supplemented VLPD increased survival and QALYs compared with the LPD. From a payer's perspective, total cost of care in Vietnam was ₫216,854,268 (€8684/$9242) per patient with LPD versus ₫200,928,819 (€8046/$8563) per patient with a supplemented VLPD (sVLPD) (difference, -₫15,925,449 [-€638/-$679]). From a patient's perspective, total cost of care in Vietnam was ₫217,872,043 (€8724/$9285) per patient with LPD versus ₫116,015,672 (€4646/$4944) per patient with sVLPD (difference, -₫101,856,371 [-€4,079/ -$4341]). From a societal perspective, total cost of care in Vietnam was ₫434,726,312 (€17,408/-$18,527) per patient with LPD versus ₫316,944,491 (€12,692/ $13,508) per patient with sVLPD (difference, -₫117,781,820 [-€4716 €/$5020). IMPLICATIONS: Ketoanalogue-supplemented VLPD lowered costs compared with LPD in all 3 perspectives considered.

Effects of Enriched Charcoal as Permanent 0.2% Feed-Additive in Standard and Low-Protein Diets of Male Fattening Turkeys: An On-Farm Study.

Wet litter is the most important cause of footpad dermatitis in poultry, this in turn being a highly relevant animal-related welfare indicator. This field study was subdivided into two experiments. In Experiment 1, the standard diet was supplemented by 0.2% enriched charcoal, being a non-specific absorber and therefore might be promising in reducing faecal moisture. In Experiment 2, the experimental group received a reduced crude protein diet during weeks 6-13, combined with a 0.2% enriched charcoal supplementation. The trials were each conducted with two batches on three farms under on-farm conditions. The animals were observed at 6, 10, 14 and 18 weeks of age to collect data on body weight and different health parameters. The mortality and litter samples were analysed after slaughtering. In Experiment 1, performance and health were not affected despite higher dry matter content of the litter. In Experiment 2, the weight of birds receiving the protein-reduced diet was decreased significantly throughout the experiment. However, the slaughter weight did not differ. The mortality was reduced by 0.5% in the experimental group. Therefore, it was concluded that 0.2% of enriched charcoal is not a valuable feed-additive regarding animal health, while temporary protein reduction might have positive effects.

Effects of inclusion of Bacillus subtilis (Gallipro) to energy- and protein-reduced diet on growth performance, nutrient digestibility, and meat quality and gas emission in broilers.

A total of 816 1-day-old Ross 308 broiler chicks with an average initial body weight (BW) of 44.01 ± 0.62 g were used in a 6-wk feeding trial. Birds were blocked based on BW and randomly allotted to 1 of 6 dietary treatments (8 replicate pens per treatment with 17 birds per replication pen) in a 3 × 2 factorial arrangement with 3 levels of metabolizable energy (ME) and crude protein (CP) with constant amino acid (100% ME and CP, 98.8% ME and CP, and 97.6% ME and CP) supplemented with or without 500 g/ton of Bacillus-based probiotics. As a result of this study, a significant reduction (P < 0.05) in BW and an increment in feed conversion rate (FCR) were observed with the reduction in the diet density during finisher and overall experiment periods. During the growing and finishing periods, the birds fed probiotic supplemented diets were heavier (P < 0.05) than those fed diets without probiotic. The FCR was also improved (P < 0.05) in probiotic supplemented groups during these periods, but feed intake (FI) remained unaffected compared to birds without probiotic supplemented diets. The apparent total tract digestibility (ATTD) of dry matter (DM) tended (P = 0.051) to be lower in ME- and CP-reduced diets compared with control. In addition, the ATTD of nitrogen (N) and energy was significantly lower (P < 0.05) in ME and CP-reduced diets than the control diet. A trend in the reduction (P = 0.059) of NH3 gas emission from the excreta was observed for birds fed ME- and CP-reduced diets compared with control diets. In addition, birds fed probiotic supplemented diets also showed reduced (P < 0.05) NH3 emission compared to those fed diet without probiotic. In conclusion, inclusion of probiotic to ME- and CP-reduced diet improved performance, had comparable effect on meat quality, and reduced ammonia emission from the excreta. No interactive effects of diet types and probiotic were observed.

Dietary N-Carbamylglutamate Supplementation in a Reduced Protein Diet Affects Carcass Traits and the Profile of Muscle Amino Acids and Fatty Acids in Finishing Pigs.

The aim of this study was to investigate whether dietary N-carbamylglutamate (NCG) supplementation in a reduced protein diet affected carcass traits and meat quality in finishing pigs. A total of 120 gilts were randomly assigned to one of four treatments for 40 days, including a standard protein diet (SP), a reduced protein diet supplemented with 1.7% l-alanine (RP + Ala), a reduced protein diet supplemented with 1.0% l-arginine (RP + Arg), and a reduced protein diet supplemented with 0.1% NCG and 1.7% l-alanine (RP + NCG). NCG supplementation increased the endogenous synthesis of l-arginine. The RP + NCG diet significantly increased the loin eye area (p < 0.05) and tended to decrease the 10th rib fat depth (p = 0.08). NCG supplementation in a reduced protein diet was effective to produce functional pork with a high content of leucine (p < 0.05). The composition of several ω-6 and ω-3 polyunsaturated fatty acids (PUFAs) but not the ratio of ω-6/ω-3 PUFAs in muscles was altered in finishing pigs with dietary NCG supplementation. In conclusion, the RP + NCG diet is effective to increase the longissimus dorsi muscle area, decrease back fat accretion, and produce functional pork with a high content of leucine but without a negative impact on the muscle fatty acid profile in finishing pigs.