Total Urinary Nitrogen Research Articles

Effects of dietary niacinamide and CP concentrations on the nitrogen excretion, growth performance, and meat quality of pigs.

Reducing the dietary CP concentration in the formulation of low-protein diets without adverse effects on animal growth performance and meat quality remains challenging. In this study, we investigated the effects of nicotinamide (NAM) on the nitrogen excretion, growth performance, and meat quality of growing-finishing pigs fed low-protein diets. To measure the nitrogen balance, we conducted two trials: in nitrogen balance trial 1, four crossbred (Duroc×Landrace×Large White) barrows (40±0.5kg BW) were used in a 4×4 Latin square design with four diets and periods. The diets consisted of a basal diet+30mg/kg NAM (a control dose), basal diet+90mg/kg NAM, basal diet+210mg/kg NAM, and basal diet+360mg/kg NAM. In nitrogen balance trial 2, another four barrows (40±0.5kg BW) were used in a 4×4 Latin square design. The diets consisted of a basal diet+including 30mg/kg NAM (control), basal diet+360mg/kg NAM, low-protein diet+30mg/kg NAM, and low-protein diet+360mg/kg NAM. To measure growth performance, two trials were conducted. In growth performance trial 1, 40 barrows (37.0±1.0kg) were randomly allocated to one of four dietary treatments (n=10 per group), whereas in growth performance trial 2, 300 barrows (41.4±2.0kg) were randomly allocated to one of four dietary treatments, with each dietary treatment conducted in five repetitions with 15 pigs each. The four diets in the two growth performance trials were similar to those in nitrogen balance trial 2. Supplementing the diet with 210 or 360mg/kg NAM reduced urinary nitrogen excretion and total nitrogen excretion and increased nitrogen retention comparted with the control diet (P<0.05). Compared with the control diet, the low-protein diet with 360mg/kg NAM reduced faecal, urinary, and total nitrogen excretion (P<0.05) without affecting nitrogen retention and average daily gain (P>0.05). Pigs fed the low-protein diet with 360mg/kg NAM showed a decreased intramuscular fat content in the longissimus thoracis muscle when compared with pigs fed the control diet (P>0.05). Our results suggest NAM as a suitable dietary additive to reduce dietary CP concentration, maximise nitrogen retention and growth performance, and decrease fat deposition in pigs.

PSII-B-20 Altering the Particle Size of Supplemental Zeolite (Clinoptilolite) in Finishing Cattle Diets: Manure Characteristics and Ammonia Emissions

Abstract A potential strategy to limit ammonia (NH3) emissions from feedlots is the feeding of supplemental clinoptilolite (CLN), which has a high affinity for ammonium (NH4+). The particle size of CLN could influence its efficacy in binding NH4+ in the rumen and manure. Therefore, our objective was to determine the effects of feeding CLN (2% of diet DM) of two different particle sizes (30 and 40 µm) on manure N profile and NH3 emissions. Six beef heifers were used in a replicated 3 × 3 Latin square design with 21 d periods. Dietary treatments were: 1) finishing ration with no supplement (CON), 2) CON + 30-µm CLN (CL-30), and 3) CON + 40-µm CLN (CL-40). Grab fecal and spot urine samples were collected (d 19 to 21) for analysis. To determine NH3 emissions, six rectangular vented, non-steady state, closed chambers interfaced with a Fourier Transform Infrared Spectroscopy analyzer were used. Soil was added to chambers to a depth of 10 cm before addition of manure and incubated over a 7-d period. Data were analyzed using SAS. There was no diet effect (P ≥ 0.78) on urinary total nitrogen (N) and urea-N concentrations. However, urinary NH3-N concentration, which was less (P = 0.03) for CON than CL-40 heifers did not differ between CON and CL-30 heifers. Fecal N concentration, which tended to greater (P = 0.07) for CL-30 than CL-40 heifers did not differ between CON and CL-40 heifers. However, there was no diet effect (P = 0.25) on fecal NH3-N concentration. Ammonia emissions, which were less (P = 0.02) for manure from CL-40 than CL-30 heifers, did not differ between CON and CL-30 heifers during the first 48 h of incubation. In summary, feeding CL with different particle sizes resulted in changes in the manure N profile and NH3 emissions.

Influence of crude protein content and flint maize processing methods on the performance of early-weaning Nellore calves

AbstractThis study aims to determine the effects of dietary crude protein (CP) content of early-weaned calves; and the influence of flint maize processing methods on intake, total tract nutrient digestibilities and performance of Nellore heifer calves. Fifteen early-weaned Nellore female calves (4 ± 0.5 months; 108 ± 13.1 kg) were used. In phase 1, animals were fed one of the following diets for 112 days: 130, 145 or 160 g CP/kg dry matter (DM). In phase 2, animals received one of the two diets for 84 days: 0.60 dry ground maize grain, 0.30 whole-plant maize silage plus 0.10 mineral-protein supplement or 0.90 snaplage plus 0.10 mineral-protein supplement. In phase 1, intake and digestibility of dietary components were not affected (P &gt; 0.05) by increasing dietary CP content. Daily total urinary nitrogen (N) and urinary urea N increased (P &lt; 0.05) in response to increasing dietary CP content. Animal performance was not affected (P &gt; 0.05) by dietary CP content. In phase 2, maize processing methods did not affect (P &gt; 0.05) intake and digestibility of dietary components as well as animal performance, carcase characteristics and carcase composition. Therefore, based on the current experimental condition, we conclude that dietary CP concentrations of 130 g/kg DM can be indicated for early-weaned Nellore calves. However, more studies are recommended to validate this result and to evaluate concentrations below 130 g CP/kg DM for early-weaned Nellore calves. Moreover, snaplage could be used as an exclusive fibre and energy source for finishing cattle in feedlot.

On-farm examination of sainfoin supplementation effects in dairy cows in a roughage-based feeding system: Indicators of protein utilisation

A case study was conducted with the objective to determine the effects of the tanniferous legume sainfoin (Onobrychis viciifolia) on protein utilisation of dairy cows, which were exposed to excessive dietary crude protein during autumn pasture grazing in a zero-concentrate feeding system. The study was conducted under practical conditions, deliberately accepting a certain lack of controllable variables. In order to assess a system applicable in practice, relatively small amounts of sainfoin were offered, and graded supply levels were compared by varying the duration of offer instead of dietary concentration. Within one dairy herd of 60 Swiss Fleckvieh cows, 30 individuals were chosen and randomly allocated to three groups balanced for milk yield, milk urea concentration, days in milk and parity. Over a period of 5 weeks, 2 kg per cow and day of sainfoin pellets were provided either intermittently, for 2 × 5 days (SST) in weeks 3 and 5 of the experiment or continuously over 35 days (SLT). A control group (CON) received 2 kg per cow and day of ryegrass pellets during the 5 weeks. The entire herd grazed on a protein-rich natural sward and was kept overnight in an open-space barn receiving fresh grass and hay ad libitum. Experimental pellets were offered individually twice per day in buckets. Feed, milk, faeces and urine samples were collected in weeks 0 (baseline), 3 and 5. Milk was analysed for fat, protein and urea, urine for purine derivatives, creatinine and nitrogen, and faeces for protein, fibre and particle fractions. During three sampling weeks, chewing activity was recorded by sensor halters. Treatment SST increased rumination time in the first half of the day, which was the only treatment effect on intake and rumination behaviour. Milk fat and protein yields were greater in SST compared to CON, but no treatment effect on concentration and yield of milk urea was found. The proportion of particle fractions in faeces was smaller in both sainfoin treatments compared to CON. In urine, the ratio of purine derivatives to creatinine tended to be higher in SST than in CON, and total urinary nitrogen excretion was lower, indicating a slightly better protein efficiency in SST. In summary, the study revealed small positive effects on protein metabolism and yield when sainfoin was applied short-term over two short periods, whereas long-term application had no effect.

Estimating purine derivatives and nitrogen compound excretion using total urine collection or spot urine samples in grazing heifers.

The study aimed to evaluate the excretion of purine derivatives (PDs) and nitrogen compounds (NCs) and their ratios with creatinine in supplemented Zebu heifers kept on pastures by comparing total urine collection and spot sampling. Five Nelore heifers (400±15kg) were used in a 5×5 Latin square design. The treatments were the amount of concentrate (220g of crude protein/kg dry matter) offered (0, 3, 6, 9 and 12g/kg BW). In each period, the total urine collection was performed continuously for 3days (subsampled at intervals of 4h, 00:00-04:00h, 04:00-08:00h, 08:00-12:00h, 12:00-16:00h, 16:00-20:00h and 20:00-24:00h). The spot urine samplings were performed (in each period) for 24h (0, 4, 8, 12, 16 and 20h). Creatinine, total urinary nitrogen (UN), urea nitrogen (UreaN), allantoin and uric acid were analysed. Creatinine excretion was 23.01±0.19mg/kg BW and was not affected by collection day, treatment or their interactions (p>0.05). Treatments affected (p<0.05) PD excretions, however did not affect the ratio PD:creatinine (p>0.05). Treatments and collection time affected (p<0.05) NC excretion, whereas the UN:creatinine and UreaN:creatinine ratios were not affected (p>0.05). Creatinine excretion and the PD:creatinine ratios in the urine samples estimated by the total or spot sampling were not different (p>0.05). However, sampling method affected (p<0.05) the UN:creatinine and UreaN:creatinine (p<0.05) ratios. Creatinine can adequately estimate urinary excretion in grazing heifers, and a single spot urine sample at any time of the day can be used to estimate PD excretion in grazing heifers. But two spot urine samples are needed for proper NC excretion estimations in grazing heifers' urine.

Corn processing and crude protein content in calf starter: Effects on growth performance, ruminal fermentation, and blood metabolites

This study aimed to investigate the effects of feeding dairy calves starter diets containing corn grain processed by different methods (ground versus steam-flaked; GRC vs. SFC) and either 18% or 21% crude protein (CP) contents (dry matter basis) on growth performance, digestibility, ruminal fermentation, urinary purine derivatives, and blood metabolites of dairy calves. Holstein dairy calves (39.3 ± 1.9 kg of body weight, n = 12 calves per treatment, 6 males and 6 females) were randomly distributed to experimental diets in a 2 × 2 factorial arrangement of treatments. The 4 dietary treatments were (1) starter diet containing GRC and 18% dietary CP (GRC-18CP; geometric mean particle size, GMPS = 0.73 mm); (2) GRC and 21% dietary CP (GRC-21CP; GMPS = 0.71 mm); (3) SFC and 18% dietary CP (SFC-18CP; GMPS = 2.21 mm); and (4) SFC and 21% dietary CP (SFC-21CP; GMPS = 2.16 mm). Calves were weaned on d 63 and remained in the study until d 83 of age. The starter feed intake did not differ among treatments; however, average daily gain and feed efficiency (FE) were improved and final body weight was higher for SFC diets compared with GRC diets. The organic matter and nonfiber carbohydrate digestibilities were greater for calves fed the SFC diets than for those fed the GRC diets. The ruminal total volatile fatty acid concentrations and the molar proportions of propionate and butyrate were greater, and the molar proportion of acetate and NH3-N concentrations were lower, for calves fed the SFC diets than for those fed the GRC diets. The excretion of allantoin and total purine derivatives, and subsequently microbial protein synthesis, were greater for calves fed the SFC diets than the GRC diets. The total urinary nitrogen excretion and its proportion of N intake were lower for calves fed the SFC diets than the GRC diets. The blood concentrations of insulin (pre- and postweaning), glucose (postweaning), and β-hydroxybutyrate (preweaning) were greater and blood urea nitrogen (preweaning) was lower for calves fed the SFC diets than the GRC diets. The protein content of the concentrate did not affect feed intake, growth performance, or ruminal fermentation of the calves. The neutral detergent fiber digestibility was greater for calves fed the 21% CP diets than the 18% CP diets. No interaction between main effects was observed regarding the starter intake, average daily gain, body weight, FE, ruminal fermentation, and nutrient digestibility of calves. The interaction between corn grain processing and starter protein content was significant for withers and hip heights with the greatest values found for SFC-21CP treatment. Our results show that steam flaking of corn improved the organic matter and nonfiber carbohydrate digestibilities, weight gain, FE, and ruminal microbial protein synthesis, and reduced urinary nitrogen excretion compared with grinding corn. Regardless of the marginal benefit derived from feeding the diet containing SFC and 21% CP in the height of calves, lower starter protein content (18% CP) may be used efficiently when calves are fed the SFC diets.

Comparison of Methods Used to Correct Self-Reported Protein Intake for Systematic Variation in Reported Energy Intake Using Quantitative Biomarkers of Dietary Intake

Multiple methods of correcting nutrient intake for misreported energy intake have been proposed but have not been extensively compared. The availability of the Women's Health Initiative (WHI) data set, which includes several objective recovery biomarkers, offers an opportunity to compare these corrections with respect to protein intake. We compared 5 energy-correction methods for self-reported dietary protein against urinary nitrogen-derived protein intake. As part of the WHI Nutritional Biomarkers Study (NBS) 544 participants (50- to 80-y-old women) completed a FFQ and biomarker assessments using doubly labeled water (DLW) for total energy expenditure (TEE) and 24-h urinary nitrogen. Correction methods evaluated were as follows: 1) DLW-TEE; 2) the Institute of Medicine's (IOM's) estimated energy requirement (EER) TEE prediction equation based on sex, height, weight, and age; 3) published NBS total energy TEE prediction (WHI-NBS-TEE) using age, BMI, race, and income; 4) reported protein versus reported energy linear regression-based residual method; and 5) a Goldberg cutoff to exclude subjects reporting energy intakes <1.35 times their basal metabolic rate. Efficacy was evaluated using correlations obtained by regressing corrected protein against biomarker protein (6.25 × urinary nitrogen/0.81). Unadjusted self-reported protein intake from the FFQ (mean=66.7g) correlated weakly (r=0.31) with biomarker protein (mean=74.9g). DLW-TEE-corrected self-reported protein intake (mean=90.7g) had the strongest correlation with biomarker protein (r=0.47). Other energy corrections yielded lower, but still significant correlations: EER, r=0.44 (mean=92.1g); WHI-NBS-TEE, r=0.37 (mean=90.4g); Goldberg cutoff, r=0.36 (mean=88.4g); and residual method, r=0.35 (mean=66.7g). Our data indicate that proportional correction of reported protein intake using a measure of energy requirement from DLW-TEE or IOM-EER performed modestly better than other methods in this cohort. These energy adjustments, however, yielded corrected protein exceeding the biomarker protein, indicating that energy adjustment alone does not eliminate all self-reported protein reporting bias.

Value of the urea/creatinine index in isolated urine to estimate severe protein hypercatabolism in ventilated patients.

ObjectiveTo study the ability of the urea/creatinine index to identify severe protein catabolism from the isolated urine of critically ventilated patients.MethodsThis was a prospective, observational study. It included 52 patients without kidney failure. Variables: total urinary nitrogen estimated from the urea in 24-hour urine on the second (T1) and fourth days (T2) and urea/creatinine index in isolated urine before 24-hour urine collection.ResultsSevere protein hypercatabolism (estimated total urinary nitrogen > 15g) was present in 14 patients (26.9%) at T1 and in 29 (55.7%) at T2. Eighty-four percent of patients had low nutritional risk by the Nutrition Risk in the Critically Ill score. At T1, the Pearson correlation between the estimated total urinary nitrogen and the urea/creatinine index was 0.272 (p = 0.051), and at T2 it was 0.276 (p = 0.048). The urea/creatinine index at T2 had a tendency to better discriminate severe protein hypercatabolism than Acute Physiology and Chronic Health Evaluation II and Nutrition Risk in the Critically Ill (AUC 0.741 versus 0.669 and 0.656, 95%CI: 0.602 - 0.880; 0.519 - 0.818 and 0.506 - 0.806, respectively). The optimal cutoff value of the urea/creatinine index for the diagnosis of severe protein hypercatabolism was 16.15, with a sensitivity of 79.31% (95%CI: 59.74 - 91.29), specificity of 60.87% (95%CI: 38.78 - 79.53), positive predictive value 71.88% (95%CI: 53.02 - 85.60), negative predictive value 70.0% (95%CI: 45.67 - 87.18), LR (+) 2.03 (95%CI: 1.18 - 3.49), and LR (-) 0.34 (95%CI: 0.16 - 0.74).ConclusionThe urea/creatinine index measured on the fourth day has a certain ability to estimate severe protein hypercatabolism (as defined by estimated total urinary nitrogen) but does not replace total urinary nitrogen in critically ventilated patients without kidney failure. Due to its reasonable sensitivity, it could be used as a screen to identify which patients to take a 24-hour urine sample from.

Twelve-Hour Urine Collection Can Be Utilized to Estimate 24-Hour Total Urinary Nitrogen in Critically Trauma Patients

Abstract Patients suffering from trauma, burns, and sepsis are frequently in a hypermetabolic state, and as the majority of urinary nitrogen comes from amino acid metabolism, the determination of total urinary nitrogen (TUN) provides an accurate measurement of all nitrogen excreted in urine and can be used as an indicator of catabolic stress. To evaluate whether time of collection influences the performance of TUN test, 12-hour urine specimens were collected from ICU trauma patients and the 12-hour results were correlated with results from 24-hour collections. Two consecutive 12-hour urine samples were collected (06:00-18:00 hours and 18:00-06:00 hours) from surgical ICU patients. Total urinary nitrogen levels were measured in each 12-hour sample, as well as in a pooled sample (24 hours). Pyrochemiluminescence was used to determine TUN level on an Antek 9000N elemental analyzer. In this approach, the urine sample is completely oxidized at high temperature in a quartz pyrotube. Nitrogen is converted to nitric oxide (·NO), then mixed with O3 (ozone) to form nitrogen dioxide (NO2). Light is emitted and specific wavelengths between 650 and 900 nm were measured in a photomultiplier tube. The measured chemiluminescent emission is specific and proportional to the amount of nitrogen in the sample. Fifty 12-hour urine samples from 16 patients were collected. One patient was excluded from the study due to acute renal injury during the collection period. There was no significant observed circadian effect on measured TUN. The 12-hour TUN (g/total volume) was multiplied by 2 to compare to 24-hour TUN for statistical analysis. There was strong correlation between either day or night 12-hour TUN and corresponding pooled 24-hour TUN, with correlation coefficients ranging from 0.93 to 0.98 and regression slopes ranging from 0.98 to 1.01. No statistically significant difference was found between the 12-hour TUN and 24-hour TUN approaches. A 12-hour TUN collection was overall highly predictive of 24-hour TUN collection and has the advantage of convenience of sample collection and improved clinical efficiency. Serial 12-hour urine collection is therefore preferred for monitoring nitrogen balance and adjusting protein intake for critically ill ICU patients.

Relationship between the NUTRIC nutritional risk scale and protein hypercatabolism in critically ventilated patients

the Nutrition Risk in Critically Ill (NUTRIC) score does not include a variable that objectively estimates protein hypercatabolism (PHC), one of the main metabolic changes experienced by critical patients. to evaluate the correlation of the NUTRIC score with PHC in critically ventilated patients. prospective, observational study. Mixed ICU. It included ventilated patients ≥ 18 years old, without anuria or chronic renal failure. The modified NUTRIC score, which replaces IL-6 for PCR, was obtained at admission and 24-hour urine was collected at the 2nd (T0) and 4th day (T1) to determine the total urinary nitrogen (TUN). a total of 69 patients were included. Average age: 43 years (± 17.01); 73% were males. Admission pathologies: trauma (39%) and sepsis (20%). 17 (± 6.66). Seventeen patients presented acute renal failure (ARF). NUTRIC score mean: 3.13 (± 1.94); 84% presented low nutritional risk. The Pearson correlation between NUTRIC and TUN in T0 and T1 was: -0.150 (p: 0.218) and -0.053 (p: 0.663). The mean length of staying in ICU and mechanical ventilation was: 13.35 (± 12.37) and 9.84 (± 10.82) days, respectively. Mortality in ICU: 36%. In the non-ARF subgroup with low risk according to NUTRIC score, 27% presented severe PHC at T0 and 52% at T1. The correlation was: 0.070 (p: 0.620) and 0.138 (p: 0.329), respectively. no correlation was found between the estimators of the stress metabolic response of the NUTRIC score and the PHC in critically ill patients ventilated; therefore, it would not be possible to substitute the measurement of the same in the assessment of the nutritional risk.

Nutritional assessment as predictor of complications after hematopoietic stem cell transplantation

IntroductionNutritional support is pivotal in patients submitted to hematopoietic stem cell transplantation. Nutritional status has been associated with time of engraftment and infection rates. In order to evaluate the association between nutritional parameters and clinical outcomes after transplantation a cohort of transplant patients was retrospectively evaluated.MethodsAll 50 patients transplanted between 2011 and 2014 were included. The nutritional status before transplantation, ten days after transplantation and before discharge was assessed including anthropometry, body mass index, albumin, prealbumin and total urinary nitrogen.ResultsThe median follow-up time was 41 months and the median age of patients was 41 years. Thirty-two underwent allogeneic and 18 autologous transplants. Diagnoses included acute leukemias (n = 27), lymphoma (n = 7), multiple myeloma (n = 13), and aplastic anemia (n = 3). Thirty-seven patients developed mucositis (three Grade 1, 15 Grade 2, 18 Grade 3 and one Grade 4), and twenty-two allogeneic, and five autologous transplant patients required total parenteral nutrition. Albumin and total urinary nitrogen were associated with length of hospital stay and platelet and neutrophil engraftment. None of the nutritional parameters evaluated were associated with overall survival. Non-relapse mortality was 14% and overall survival was 79% at 41 months of follow-up.ConclusionsAfter hematopoietic stem cell transplantation, high catabolism was associated with longer length of hospital stay, the need of total parenteral nutrition and platelet and neutrophil engraftment times. Nutritional parameters were not associated with overall survival.

EFFECT OF DIFFERENT SOURCES OF NITROGEN ADDING TO GROUND DATE PALM STON ON LOCAL KIDS PERFORMANCE

This experiment was conduct at Ruminant Research Station/State Board for Agricultural Research/Ministry of Agriculture for the period from 01/ 02/ 2012 until 03/05/2012. The experiment lasted 93 days .Twenty crossbred growing male goats weighted 26.11 ± 1.91 kg and 7-8 month old were equally divided into five groups (4 animals/ treatment).The dietary treatments were as follows: T1:concentrat diet without ground dates stone ,T2:concentrate diet contain 30% ground dates stone and 0.80 % urea, T3: concentrate diet contain 30% ground dates stone and 1.20 % urea, T4: concentrate diet contain 30% ground dates stone and 5.80 % soybean meal, T5: concentrate diet contain 30% ground dates stone and 7.80 % soybean meal. Animals were fed concentrate at the level of 2.5% of body weight, alfalfa hay was given as ad libitum basis as the roughage.Results showed that total and daily weight gain and feed conversion efficiency had higher values (P<0.05) in diet T5 than the other experimental groups. The in vivo crude protein digestibility was significantly (P<0.05) higher in T1 compared to other groups. The highest (P<0.05) value of nitrogen free extracts and crude fiber digestibility were recorded in groups T4 and T5. Total digestible nutrients (TDN) was significantly (P<0.05) higher in group T1. Moreover, nitrogen intake showed higher values (P<0.05) in groups T2 and T3. Fecal and urinary nitrogen and total nitrogen secreted was maximum in group T5. Digestible and retained nitrogen were highest (P<0.05) in T5.

How much protein and energy are needed to equilibrate nitrogen and energy balances in ventilated critically ill children?

Protein and energy requirements in critically ill children are currently based on insufficient data. Moreover, longitudinal measurements of both total urinary nitrogen (TUN) and resting energy expenditure (REE) are lacking. The aim of this study was to investigate how much protein and energy are needed to equilibrate nitrogen and energy balances in ventilated critically ill children on the basis of daily measurements of TUN, REE and protein and energy intakes. Comparisons were made with the guidelines of the American Society for Parenteral and Enteral Nutrition and the Dietary Reference Intakes. Children with an expected duration of mechanical ventilation ≥72h were prospectively recruited. TUN was measured by chemiluminescence, and REE was measured by indirect calorimetry. Generalised linear models for longitudinal data were used to study the relation between protein intake and nitrogen balance and to calculate the minimum intake of protein needed to achieve nitrogen equilibrium. A similar approach was used for energy. Results were compared to the recommended values. Based on 402 measurements performed in 74 children (median age: 21 months), the mean TUN was high at 0.20 (95% CI: 0.20, 0.22) g/kg/d and the REE was 55 (95% CI: 54, 57) kcal/kg/d. Nitrogen and energy balances were achieved with 1.5 (95% CI: 1.4, 1.6) g/kg/d of protein and 58 (95% CI: 53, 63) kcal/kg/d for the entire group, but there were differences among children of different ages. Children required more protein and less energy than the Dietary Reference Intakes. In critically ill children, TUN was elevated and REE was reduced during the entire period of mechanical ventilation. Minimum intakes of 1.5g/kg/d of protein and 58kcal/kg/d can equilibrate nitrogen and energy balances in children up to 4 years old. Older children require more protein.

Nutritional Assessment As Predictor of Complications Post Hematopoietic Cell Transplantation

▪INTRODUCTION: Nutritional support is pivotal in patients with hematologic malignancies and hematopoietic cell transplantation (HCT). Optimal nutritional status is associated with a shorter time of engraftment and less infection rates during the initial phase. We present our experience in nutritional assessment pre and post transplantation.OBJECTIVE: To evaluate the possible association between nutritional parameters and outcomes such as overall survival and specific complications, in patients who underwent HCT.PATIENTS AND METHODS: Retrospective study in patients with HCT between June 2011 and May 2014 in our center. We assessed nutritional status before transplantation and then 10 days after it. Nutritional assessment included anthropometry, body mass index (BMI), albumin, prealbumin and total urinary nitrogen (TUN). Statistical analysis was made using IBP SSPS v.20.RESULTS: We studied a total of 50 patients between June 2011 and May 2014. Media following time: 35 months. Median age was 41 years (18-67), 33 (66%) were male and 17 (33%) female. Thirty two underwent (64%) allogeneic HCT and 18 (36%) autologous HSCT, with 42 undergoing (84%) myeloablative conditioning and 8 (16%) reduced intensity conditioning. Diagnoses included acute leukemia (26), lymphoma (7), multiple myeloma (13), and aplastic anemia (3). Thirty seven patients developed mucositis and 31 required parenteral nutrition (PN). Twenty three patients developed mucositis and required PN (mild: 2, moderate: 20, severe: 1) Incidence of mucositis between allogeneic and autologous HCT that required PN was similar (75% vs 72%). Albumin levels were 4,1mg/dL before and 3,3 mg/dL 10 days after HSCT (p< 0,05). No difference was found between BMI, dynamometry and TUN before and after HCT. TUN before HCT was associated with more days of PN (p<0,05). Multivariate analysis showed an association between lower albumin levels after HCT and PN requirement, as well as a longer length of stay. High TUN and lower albumin levels after HCT were associated with longer platelet engraftment time (p<0.05). Longer engrafment time was associated with longer duration of PN (p<0,05). Nine patients (28%) in the allogeneic group developed acute gastrointestinal graft versus host disease (GVHD) that required prolonged PN. No association was found between BMI, albumin, prealbumin, TUN or requirement of PN, with the risk of mucositis or infectious complications. None of the evaluated nutritional parameters were associated with overall survive (OS).CONCLUSION: High catabolism was associated with a longer length of stay, the requirement of PN and a prolonged platelet engraftment time. Acute gastrointestinal GVHD was associated with more requirement and a longer duration of PN. Nutritional parameters were not associated with any risk of infection and OS. DisclosuresNo relevant conflicts of interest to declare.

A snapshot of nitrogen balance in endurance-trained women

Indirect estimates of the mean daily protein requirement for female endurance athletes are 1.2-1.4 g·kg(-1)·day(-1); however, an empirical estimate using nitrogen balance is absent. A 72-h nitrogen balance was determined during the mid-follicular phase of 10 female cyclists and triathletes training for 10.8 h·week(-1) (SD 2.8) following 2 habituated protein intakes: (i) normal habitual (NH) (protein 85 g·day(-1)), and (ii) isocaloric high-protein (HP) (∼2-fold increase in protein). Total 72-h nitrogen intake was determined from Leco total combustion of ingested food samples. Nitrogen loss was determined from micro-Kjeldahl analysis of 72-h total urinary nitrogen and representative resting and exercise sweat output, plus estimates for fecal and miscellaneous losses. Habituated (steady state) protein requirement was estimated from the mean regression of adapted nitrogen balance vs nitrogen intake. Mean (SD) 24-h dietary protein and energy intake was NH: 1.4 g·kg(-1)·day(-1) (0.2), energy: 9078 kJ·day(-1) (1492), HP: 2.7 g·kg(-1)·day(-1) (0.3) 8909 kJ·day(-1) (1411). Average 24-h urinary nitrogen and sweat urea nitrogen outputs were 13.2 g·day(-1) (2.4) and 0.33 g·day(-1) (0.08) in NH; 21.5 g·day(-1) (3.9) and 0.54 g·day(-1) (0.12) in HP, respectively. Nitrogen balance was negative in NH (-0.59 gN·day(-1) SD 1.64) but positive in HP (2.69 gN·day(-1) SD 3.09). Estimated mean protein requirement was 1.63 g·kg(-1)·day(-1) (95% confidence interval: 1.1-3.8). In conclusion the snapshot of follicular phase dietary protein requirement conformed with previous estimates for men, but was higher than previous nonempirical estimates for endurance-training women; low self-selected energy and carbohydrate intakes may explain the higher than expected nitrogen turnover, and consequently protein requirement.

Prediction of urinary nitrogen and urinary urea nitrogen excretion by lactating dairy cattle in northwestern Europe and North America: A meta-analysis

A meta-analysis was conducted on the effect of dietary and animal factors on the excretion of total urinary nitrogen (UN) and urinary urea nitrogen (UUN) in lactating dairy cattle in North America (NA) and northwestern Europe (EU). Mean treatment data were used from 47 trials carried out in NA and EU. Mixed model analysis was used with experiment included as a random effect and all other factors, consisting of dietary and animal characteristics, included as fixed effects. Fixed factors were nested within continent (EU or NA). A distinction was made between urinary excretions based on either urine spot samples or calculated assuming a zero N balance, and excretions that were determined by total collection of urine only. Moreover, with the subset of data based on total collection of urine, a new data set was created by calculating urinary N excretion assuming a zero N balance. Comparison with the original subset of data allowed for examining the effect of such an assumption on the relationship established between milk urea N (MUN) concentration and UN. Of all single dietary and animal factors evaluated to predict N excretion in urine, MUN and dietary crude protein (CP) concentration were by far the best predictors. Urinary N excretion was best predicted by the combination of MUN, CP, and dry matter intake, whereas UUN was best predicted by the combination of MUN and CP. All other factors did not improve or only marginally improved the prediction of UN or UUN. The relationship between UN and MUN differed between NA and EU, with higher estimated regression coefficients for MUN for the NA data set. Precision of UN and UUN prediction improved substantially when only UN or UUN data based on total collection of urine were used. The relationship between UN and MUN for the NA data set, but not for the EU data set, was substantially altered when UN was calculated assuming a zero N balance instead of being based on the total collection of urine. According to results of the present meta-analysis, UN and UUN are best predicted by the combination of MUN and CP and that, in regard to precision and accuracy, prediction equations for UN and UUN should be derived from the total collection of urine.

Effect of different rumen degradable nitrogen levels on microbial protein synthesis and digestibility in sheep fed on finger millet straw (Eleucine coracana) based diet

Studies were conducted to determine adequate rumen degradable nitrogen (RDN) levels for optimum microbial protein synthesis and digestibility of nutrients in adult Bandur sheep fed on finger millet straw (FMS) based diet. Thirty Bandur sheep were divided into five groups of six animals each using a balanced completely randomized design. Animals in all groups were fed FMS as a basal roughage and solvent-extracted soybean meal (SBM) as a nitrogen source. The sheep in group 1 (G1) were offered FMS for ad libitum intake. Animals in group 2, 3, 4 and 5 (G2, G3, G4 and G5) were supplemented with SBM to provide RDN level of 16.2, 20.7, 24.7 and 26.6g/kg digestible organic matter intake (DOMI) or 24.9, 31.8, 38.1 and 41.0g/kg digestible organic matter apparently digested in the rumen (DOMR) respectively, along with FMS. The daily total dry matter (DM) and organic matter (OM) intakes showed a linear increase (P<0.05) with increasing levels of RDN supplementation. Digestibility coefficients of DM, OM (linear: P<0.01), crude protein (CP), ether extract (EE) (quadratic: P<0.001), neutral detergent fiber (NDF) and acid detergent fiber (ADF) (quadratic: P<0.05) increased as the level of RDN supplementation increased from G1 to G5. The values for total purine derivatives (TPD) excretion (mmol/day and mmol/kgW0.75) (quadratic: P<0.05), the levels of microbial purine absorption and microbial nitrogen supply (MNSg/day, g/kgDOMI and g/kgDOMR) (quadratic: P<0.01) increased, while microbial nitrogen to total urinary nitrogen ratio (MN:UN) decreased (linear: P<0.01) with the increased RDN level, indicating the efficient conversion of RDN into microbial protein synthesis for G2 animals among the RDN supplemented groups. This study indicated that 16gRDN/kgDOMI or 25gRDN/kgDOMR may be adequate for optimum microbial protein synthesis and digestibility of nutrients, thereby improving plane of nutrition in sheep fed on finger millet straw based diet. The additional RDN supplied beyond certain limit (above 16gRDN/kgDOMI or 25gRDN/kgDOMR) may not be beneficial for improving the digestibility of diet especially on straw based diets.

Rumen degradable nitrogen requirements for optimum microbial protein synthesis and nutrient utilization in sheep fed on finger millet straw (Eleucine coracana) based diet

Studies were conducted to determine the rumen degradable nitrogen (RDN) requirement levels for optimum microbial protein synthesis and nutrient utilization in Nellore rams fed on finger millet straw (FMS) based diet. Thirty six Nellore sheep were randomly divided into four groups of nine animals each using the balanced completely randomized design. Animals in all the groups were fed finger millet straw as a basal roughage and groundnut cake (GNC) was offered daily in two equal halves in the morning (8.00AM) and evening (4.00PM) as RDN source. The animals in group I (GI) were fed with ad libitum FMS. Animals in group II, III and IV (GII, GIII, and IV) were offered GNC @ 12.4, 16.6, and 21.1g RDN/kg digestible organic matter (DOM) along with FMS. The daily total dry matter (DM) and organic matter (OM) intakes linearly increased (P<0.05) with increasing level of RDN supplementation while there was no difference in total DM and OM intake/kg W0.75 among different experimental groups. The digestibility coefficients of DM (P<0.001), OM (P<0.001), crude protein (CP) (P<0.001), ether extract (EE) (P<0.001), neutral detergent fibre (NDF) (P<0.01) and acid detergent fibre (ADF) (P<0.03) increased quadratically with increasing level of RDN supplementation from GI to GIV. The purine derivatives (PD) excretion, microbial purine absorption and microbial nitrogen supply (MNSg/day) linearly increased (P<0.001) as the level of RDN supplementation increased. There was no difference in nitrogen capture efficiency (NCE) and microbial nitrogen to total urinary nitrogen ratio (MN:UN) among the RDN supplemented groups. This study indicated that 12g RDN/kg digestible organic matter intake (RDNg/kg DOMI) or 18g RDN/kg OM apparently digested in the rumen (RDNg/kg DOMR) may be adequate for optimum microbial protein synthesis and digestibility of nutrients, there by improved plane of nutrition in sheep fed on finger millet straw based diet.

Digestão dos nutrientes e balanço de compostos nitrogenados em cabras alimentadas com quatro níveis de proteína

Avaliaram-se o consumo de alimentos, o pH e a concentração ruminal de amônia em quatro cabras, nas quais se coletou digesta de omaso via fistula ruminal para estimativa da digestão ruminal dos nutrientes. Para avaliação dos compostos nitrogenados (N), totais urinários de N-uréia no soro (NUS), no leite (NUL) e na urina utilizaram-se 12 cabras não fistuladas, distribuídas em três quadrados latinos 4x4. Os animais foram alimentados com rações constituídas de 50% de silagem de milho e de 50% concentrado à base da matéria seca (MS), e as dietas continham 11,5; 13,5; 15,5 e 17,5% de proteína bruta na MS. Com exceção da proteína, os consumos e digestibilidades dos demais nutrientes não foram influenciados pelos níveis de PB nas dietas. O pH ruminal diminuiu após o fornecimento de alimento. Com o aumento no consumo de N, ocorreram aumentos na concentração ruminal de amônia, nas concentrações de NUS e NUL, no volume urinário e no balanço de N. Conclui-se que o nível de 13,5 % ou 245 gramas de PB é suficiente para cabras com produção diária de 1,6kg de leite e que o método de coletas de digesta no omaso precisa ser avaliado criteriosamente para sua validação em caprinos.

Pharmacology Review: Sodium Phenylacetate and Sodium Benzoate in the Treatment of Neonatal Hyperammonemia

Ammonia is present in all body fluids and exists primarily as ammonium ion at physiologic pH. Hyperammonemia is defined as a blood ammonia concentration greater than about 100 mcmol/L in neonates or 50 mcmol/L in children and adults (precise cut-offs vary, depending on individual laboratory normative ranges). The concentration of ammonia is 10 times higher in tissue than in blood. A 5- to 10-fold increase in blood ammonia concentration usually is toxic to the nervous system. Hyperammonemia in the neonatal period, especially when due to inborn errors of metabolism, can progress rapidly and cause severe neurologic damage or early death. Hyperammonemia can be caused by inborn errors of metabolism as well as by a variety of acquired conditions (Tables 1 and 2). Urgent treatment is required because of the potential for irreversible neurologic sequelae that can, in many cases, be prevented by prompt diagnosis and institution of therapy. | Urea cycle defects | || | Amino acid transporter deficiencies | | Organic acidemias | | Fatty acid oxidation defects | | Pyruvate carboxylase deficiency | | Mitochondrial disorders | | Hyperinsulinism/hyperammonemia syndrome (glutamate dehydrogenase mutations) | | Delta1-pyrroline-5-carboxylate synthase deficiency | Table 1. Inborn Errors of Metabolism Associated With Hyperammonemia | Sampling artifact | || | Cardiovascular | | Perinatal asphyxia | | Liver failure | | Bacterial colonization (urease-positive organisms) | | Iatrogenic | Table 2. Causes of Acquired Hyperammonemia The combination of sodium phenylacetate (NAPA) and sodium benzoate (NABZ) in a 10%/10% solution is an intravenously administered United States Food and Drug Administration (FDA)-approved drug used as adjunctive therapy for …