Feasibility of achieving different protein targets using a hypocaloric high-protein enteral formula in critically ill patients

Background and aims Combining energy and protein targets during the acute phase of critical illness is challenging. Energy should be provided progressively to reach targets while avoiding overfeeding and ensuring sufficient protein provision. This prospective observational study evaluated the feasibility of achieving protein targets guided by 24-h urinary nitrogen excretion while avoiding overfeeding when administering a high protein-to-energy ratio enteral nutrition (EN) formula. Methods Critically ill adult mechanically ventilated patients with an APACHE II score > 15, SOFA > 4 and without gastrointestinal dysfunction received EN with hypocaloric content for 7 days. Protein need was determined by 24-h urinary nitrogen excretion, up to 1.2 g/kg (Group A, N = 10) or up to 1.5 g/kg (Group B, N = 22). Variables assessed included nitrogen intake, excretion, balance; resting energy expenditure (REE); phase angle (PhA); gastrointestinal tolerance of EN. Results Demographic characteristics of groups were similar. Protein target was achieved using urinary nitrogen excretion measurements. Nitrogen balance worsened in Group A but improved in Group B. Daily protein and calorie intake and balance were significantly increased in Group B compared to Group A. REE was correlated to PhA measurements. Gastric tolerance of EN was good. Conclusions Achieving the protein target using urinary nitrogen loss up to 1.5 g/kg/day was feasible in this hypercatabolic population. Reaching a higher protein and calorie target did not induce higher nitrogen excretion and was associated with improved nitrogen balance and a better energy intake without overfeeding. PhA appears to be related to REE and may reflect metabolism level, suggestive of a new phenotype for nutritional status. Trial registration 0795-18-RMC.

Functional diversity vs monotony: The effect of a multi-forage diet as opposed to a single forage diet on animal intake, performance, welfare, and urinary nitrogen excretion

The objective of this study was to determine the effect of offering animals a multi-forage choice of fresh herbages on dry matter intake (DMI), live weight gain and animal welfare, in comparison with a monotonous diet of ryegrass (Lolium perenne L.). Twenty ram lambs [30.5 ± 0.9 kg initial live weight; mean ± standard error of the mean], were randomly allocated to either a diet consisting of diverse multi-forage choice (MF) or a single forage ryegrass (SF) diet (n = 10 per treatment) for 35 days. Both diets were fed ad libitum; however, the MF diet was composed of set dry matter ratios of: 24% chicory (Cichorium intybus L.), 30% lucerne (Medicago sativa L.), 25% plantain (Plantago lanceolata L.), and 21% ryegrass. The DMI of the MF lambs was 48% greater (P < 0.01) and the within animal day-to-day coefficient of variation (CV) of intake was 26% lower (P < 0.01) than the SF lambs. The average daily gain (ADG) of lambs offered the MF diet was 92% greater (P < 0.01) than the lambs offered the SF diet. The within animal day-to-day CV of intake was negatively related with ADG (r = -0.59: P < 0.01). The MF lamb’s urinary N concentration was 30% lower (P < 0.01) than that of the SF lambs. The SF lambs spent more time (P < 0.05) exhibiting stereotypic behaviors in the afternoon and spent more time observing other animals than the MF. Overall, allocating a multi-forage choice of fresh herbages as opposed to a single forage diet of ryegrass increases DMI and thereby animal performance, while potentially reducing urinary N excretion.

Urea Utilization by Cattle as Influenced by Casein

THE influence of casein on urea-nitrogen utilization by cattle was investigated in two studies. In a fattening study, the inclusion of casein to a soybean meal (SBM) or urea-supplemented ration depressed both average daily gain (ADG) and average daily feed intake (P<.05}. Casein addition, on the other hand, significantly (P <.05 increased rumen :ammonia concentration. The second and metabolism study involved the use of identical rations as in the fattening study. Cattle fed rations with casein did not show any significant decrease in nitrogen retention as compared to cattle fed rations without casein. However, there was a non-significant drop in nitrogen retention, and an increase in urinary nitrogen excretion attributable to casein. Ruminal histamine observed for steers on the fattening study was higher than that noted for steers on the metabolism study. Part of the poor performance of steers on the casein diets could be attributed to the higher urinary nitrogen excreted and the elevated ruminal histamine levels observed.

Urinary nitrogen excretion at the early stage of severe acute pancreatitis

Aim. To study urinary nitrogen excretion at the early stage of severe acute pancreatitis. Materials and methods. Prospective, single-center, cohort study. Inclusion criteria: diagnosis of acute pancreatitis and presence of at least one of the predictors of severe course. Among all patients (n = 72), a cohort of patients with severe acute pancreatitis (n = 32) was allocated. Three groups were formed in it: the first one – all patients, the second one – survivors (n = 24), the third one – deceased (n = 8). Urinary nitrogen excretion was determined using the Deacon formula. Measurements were performed on the first, third and fifth days of the disease. Statistical processing of the material was carried out by the SPSS software package. The null hypothesis was rejected at p < 0.05. Results. In the first week of the disease in all groups, the maximum urinary nitrogen excretion occurs on the 3rd day. When comparing the results of the second and third groups, it was found that the urinary nitrogen excretion on the first and fifth days did not have a statistically significant difference between the groups (respectively, p = 0.138, p = 0.572), and the results of the third day have (p = 0.014). A similar pattern remains when recalculating the nitrogen loss in the urine to the ideal weight; for the third day, the differences between the second and third groups were statistically significant (p = 0.007). ROC analysis of urinary nitrogen excretion of the third day calculated to the ideal body weight showed an area under the curve of 0.813 (p < 0.009). The value at the cut-off point is defined as 0.65 g/kg/day. The sensitivity of the model was 0.75%, specificity – 0.83%. Conclusion. If in a patient with acute pancreatitis, there is urinary nitrogen excretion on the third day from the onset of the disease, calculated to an ideal body weight of ≥ 0.65 g/kg/day, an unfavorable outcome of the disease is predicted.

Effects of enriched mesquite piperidine alkaloid extract in diets with reduced crude protein concentration on the rumen microbial efficiency and performance in lambs

The objective of this study was to evaluate the effects of enriched mesquite piperidine alkaloid (MPA) extract at 31 mg/kg of dry matter (DM) in diets with 16% or 13% of crude protein (CP) compared to a diet with 16% CP without additive (control) and diets with monensin (MON) at 31 mg/kg DM and 16% or 13% CP. The intake, ingestive behaviour, apparent digestibility, body weight gain, microbial protein synthesis and nitrogen balance were evaluated. A total of 30 uncastrated crossbred Santa Inês × Bergamasca lambs were used and allocated in a completely randomized design. No effects of additives on dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), and non-fibre carbohydrate (NFC) intake were observed in diets with 16% and 13% CP compared to the control diet. The total digestible nutrient intake (g/kg BW) for the diet with MPA 13% CP was lower than for the control diet, while the metabolisable energy intake (MJ/kg BW) did not differ between diets. The DM feeding rate (g/min) was reduced for the diet with MON 13% CP compared to the control diet. There was no difference between MON or MPA with CP 16% or 13% and the control diet in the digestibility of DM, OM, NFC, and NDF. MON in the diet with 13% CP reduced the BW gain, which differed from the control diet, while MPA 13% CP did not differ from the control diet. The microbial protein synthesis efficiency was higher for diets with MPA compared to MON 13% CP and the control diet. Dietary nitrogen retention (g/kg metabolic weight) was lower in diets with 13% CP that differed from the diets with 16% CP. The nitrogen retained as a percentage of ingested and digested nitrogen was unchanged with the use of MPA or MON 13% CP due to lower urinary nitrogen excretion. The MPA 13% CP diet does not affect the performance of lambs by increasing the microbial synthesis efficiency in the rumen.

Protein metabolism in the organism of growing borrows at the addition of 20-hydroxyexdisone to the diet

One of the approaches to the creation of biologically active additives in pig nutrition can be the use of phytopreparations, in par-ticular, 20-hydroxyecdysone (20-GE), which regulates protein metabolism in piglets. The aim of this work is to assess the effect of 20-GE on the metabolism of proteins in the body and to measure their turnover in grow-ing boars. The experiment was carried out on boars (♂ Danish Yorkshire × ♀ Danish Landrace) from 60 to 120 days of age. At the age of 60 days, boars were divided into 2 groups: control and experimental, fed with feed with a content (g / kg) of crude protein 158.7, lysine 7.7, threonine 4.8, methionine 4.6, exchange energy (EE) 12.7 MJ / kg. The ratio of the first limiting amino acid lysine to EE was 61%. The boars of the experimental group were injected with 20-GE at a dose of 1.6 mg / kg of body weight. In boars of the experimental group, compared with the con-trol, there was a decrease in urinary nitrogen excretion (by 26.8%, P≤0.05). Nitrogen re-tention was higher in boars of the experi-mental group by 19.0% (P≤0.001) compared to the control. The results of studies on pro-tein turnover obtained using a stable isotope indicate that the anabolic effect of 20-GE isdetermined by an increase in the rate of pro-tein synthesis at the same rates of their deg-radation, nitrogen flow against the back-ground of a decrease in its endogenous loss-es. 20-GE by activating a signal through protein kinase B provides an increase in bio-synthetic processes at the stage of transla-tion. It was concluded that the use of 20-GE in boars cultivation increases the efficiency of using amino acids for the synthesis and deposition of proteins in the body.

Resting energy expenditure and urinary nitrogen excretion during stress-induced hyperglycemia at an early phase of acute severe pancreatitis

Purpose. To investigate the features of resting energy expenditure and urinary nitrogen excretion during stress-induced hyperglycemia at an early phase of acute severe pancreatitis. Materials and methods. The study design was a prospective single-center cohort study. The inclusion criteria were: diagnosed acute pancreatitis and at least one severity predictor. On day one, three, and five the dark blood glycemic index and urinary nitrogen excretion were measured and resting energy expenditure was determined in all patients. From the total number of cases (n = 72), a cohort of patients with severe acute pancreatitis was singled out (n = 23). In that cohort, three groups were formed. The first group included measurements made over the whole observation period (n = 69), the second – normoglycemia (n = 48), and the third one – hyperglycemia. Stress-induced hyperglycemia was determined as increased blood glucose ≥ 11.1 mmol/L. The raw data were statistically processed using SPSS package. The zero hypothesis was rejected at p < 0.05. Results. A statistically significant difference was found between the second and third groups in the glycemia index (p < 0.001) and urinary nitrogen excretion (p = 0.022), but not in the resting energy expenditure (p = 0.157). The prevalence of glycemia among the deceased amounted to 66.6% and among the survived – 17.2%. To make up the quantity of nitrogen lost with urine, the normoglycemia patients required an uptake of 117.1 nonprotein kcal per 1 g of nitrogen, and the hyperglycemia patients -61.7 kcal. Conclusion. At an early phase of acute severe pancreatitis, urinary nitrogen excretion rises in a statistically significant manner in patients with stress-induced hyperglycemia. To make up the urinary nitrogen loss, the normoglycemia patients require 117.1 nonprotein kcal per 1 g of nitrogen while hyperglycemia patients – 61.7.

Levels of protected lysine and methionine in the diet of lambs: nutritional parameters and protein metabolites

The objective of this study was to evaluate the effect of inclusion of different levels of protected lysine and methionine on the nutritional parameters and protein metabolites of lambs. The experiment was carried out at the Capim Branco Experimental Farm, at Uberlândia Federal University, during the months of September and October 2016. Five blood lambs ½ Dorper × ½ Santa Inês, approximately eight months old and with an average weight of 50 kg, were distributed in a Latin square scheme 5 × 5 (five treatments and five replicates). The treatments consisted of the inclusion in the diet of different levels of lysine and methionine protected from ruminal degradation (MicroPEARLS LM®): 0 g, 8 g, 16 g, 24 g, and 32 g. The diet was composed of corn silage and concentrate in a ratio of 30V:70C. The experiment was divided into five phases. Each phase had a duration of fifteen days (ten days of adaptation of the animals to the experimental diets and five days of data collection). The animals were kept in individual metabolic cages. A digestibility assay was performed to determine the apparent dry matter intake and digestibility (DMI/DDMI), nitrogen balance, and protein metabolites. The DMI (kg day-1) and in relation to the metabolic weight presented a positive linear equation, and was highest for the treatment with 32 g of amino acids, as well as the ingested nitrogen and nitrogen balance, being positive in all treatments. There was no difference (P > 0.05) in the DDMI. The crude protein and urea concentrations remained above the recommended levels and the concentration of creatinine remained below the recommended level. The inclusion of protected amino acids up to 32 g increases DMI and urinary nitrogen excretion without negatively affecting digestibility. The protein metabolism was altered, without causing damage to the performance of the animals.