Output Of Nitrogen In Urine Research Articles

Effects of Dietary Fiber, Crude Protein Level, and Gestation Stage on the Nitrogen Utilization of Multiparous Gestating Sows

Simple SummaryTwo major concerns for sustainable swine production are the shortage of protein feed resources and the excretion of nitrogen and phosphorus into the environment. Those concerns can be partly alleviated by increasing nitrogen utilization by improving nutrition for pigs. This study observed that a low crude protein and dietary fiber supplemented diet can improve nitrogen utilization and reduce urinary nitrogen excretion. Additionally, late gestating sows have greater nitrogen utilization than those of early gestation, characterized by reduced nitrogen in urine and lower amino acids in serum. These findings offer nutritional solutions for improving nitrogen utilization.To investigate the effects of dietary fiber (DF), crude protein (CP) level, and gestation stage on nitrogen utilization, 28 Landrace-Yorkshire cross gestating sows at parity two were randomly divided into four dietary treatments with seven duplicates of one pig with a repeated-measures design. The diets comprised one with normal crude protein (CP) of 13.3%, one with a low CP diet of 10.1%, and two diets, one with dietary fiber (DF) supplementation of inulin and cellulose at the ratio of 1:1 and one without DF. The total litter size, litter size alive, and newborn birthweight of piglets did not differ between treatment groups. Sows that received high DF levels had greater nitrogen output in feces, lower urinary nitrogen, and increased nitrogen retention. Sows that received a low CP diet had reduced nitrogen excretion in feces and urine, lower nitrogen retention, and an unchanged nitrogen retention ratio. Sows at the late stage of gestation on days 95 to 98 had lower nitrogen excretion in urine and greater nitrogen retention than in the early stage of gestation on days 35 to 38, associated with a significant decrease in serum amino acids in late gestation. Maternal protein deposition was increased by high DF, decreased by low CP, and lower in late gestation compared with early gestation. Collectively, DF improved nitrogen utilization by decreasing urine nitrogen output, and nitrogen utilization increased as gestation advanced.

Relationships of both urine nitrogen output and plasma urea concentration with rumen protein balance in lactating goats

The updated INRA system incorporates the notion of rumen protein balance (RPB, g CP/kg DM) in an attempt to better fit feed evaluation, animal requirements and responses to diets. RPB is the difference between crude protein intake and entrance at the duodenum (excluding NH3) which is not very easy to measure in vivo. The aim of this study was to test the strength of the relationships between dietary RPB values obtained from the diet composition and criteria easier to measure, such as N urinary outputs or plasma urea concentration, both at a treatment level and at an individual level in a large dataset obtained from lactating goats fed different types of diets. RPB was a better predictor of urinary N output and plasma urea concentration than was the former French system for protein digestible in the intestine. Within experiments, RPB was highly and positively correlated with urinary nitrogen outputs and plasma urea concentration. RPB can be used to estimate the urinary N output in lactating dairy goats, but this study also showed that some of the residual variance was due to variability among animals.

Supplementation of Dry Brewer's Grain to Lower Quality Forage Diet for Growing Lambs in Southeast Nigeria

Twenty yearling lambs of Southeast Nigeria dwarf, liveweight (18±1.9 kg) were grouped into 5 treatments. Dry brewer's grain was substituted for maize offal in the experiment diets namely A to E at 0%, 15%, 30%, 45% and 60% respectively, as supplement to low quality, dry season cassava leaf top and Andropogan gayanus hay at 1:1 ratio that lasted for 56 days. After which 5 of the lambs (average bodyweight=24.3±1.5 kg) were transferred to metabolism crates to determine the digestibility and nitrogen/protein balance studies. While the mean group intakes were (945.9, 996.1, 1,040.5, 1,148.5 and 1,037.7 g conc. DM/day), the growth rates were (115.1, 124.1, 152.5, 168.5 and 123.1 g liveweight gain/day), respectively. There was a recorded decline in both intake (p>0.05) and growth rate (p 0.05) together with the organic matter intake. The urine nitrogen output was also significant (p>0.05). The work further revealed that, at a certain critical level of intake, dry brewer's grain is able to support growth rates measurable to or better than those noted when feeding maize offal to lambs, and went on to prove dry brewer's grain as an attractive supplementary feed for the drier months of the year, in the Southeast of Nigeria. (Asian- Aust. J. Anim. Sci. 2003. Vol 16, No. 3 : 384-388)

Effects of Postrumen Starch Infusion on Milk Production and Energy Metabolism in Dairy Cows

Two experiments were conducted to determine effects of postrumen starch infusion on milk production and energy and nitrogen utilization in lactating dairy cows. In experiment 1, four cows in early lactation fed grass silage and concentrates were continuously infused into the duodenum with water or 700, 1400, or 2100g of purified maize starch daily for 10 to 12 d in a 4×4 Latin square design with 2-wk periods. Starch infusion increased milk yield linearly and decreased milk fat concentration in a quadratic manner such that increases in fat-corrected milk and calculated milk energy yield were minimal except at the highest rate of infusion. Changes in milk energy output suggest that even at the highest infusion rate metabolizable energy supplied by infused starch was used for tissue energy or oxidized. In experiment 2 energy and nitrogen balance were measured in four cows in late lactation fed a mixture of dehydrated lucerne, grass silage, and concentrates during the last 6 d of 2-wk abomasal infusions of 1200g of purified wheat starch daily or water in a balanced switchback design with 5-wk periods. Measurements of fecal starch concentration indicated nearly all the starch infused was digested, but decreased fecal pH and apparent nitrogen digestion suggested an increase in hindgut starch fermentation. Starch infusion decreased urine nitrogen output in part because of increased tissue nitrogen retention but had no effect on milk nitrogen output. In absolute terms, numerical decreases in feed energy intake and energy digestion reduced the recovery of starch energy infused as digestible and metabolizable energy, but in terms of changes in total energy supply with starch infusion, 79% was recovered as metabolizable energy. Starch infusion had no effects on heat or milk energy but increased net energy for lactation due to a numerical increase in tissue energy, implying that in late-lactation cows, starch digested postruminally was used with high efficiency for tissue energy retention as protein and fat.

THERAPEUTIC AND NUTRITIONAL EFFECT OF AN ORAL REHYDRATION SOLUTION (ORS) CONTAINING GLUTAMINE. A DOUBLE BLIND RANDOMISED STUDY IN 44 DIARRHEIC INFANTS.

The ORS as recommended by the World Health Organisation (WHO) has been a major advance in the treatment of acute diarrhea in children. The ideal composition of the ORS is still controversial, as regards sodium levels, as well as, other proposed components ie. amino-acids or cereals. It has been demonstrated that amino-acid glutamine has an effect on sodium absorption, enterocyte metabolism, immunity and nutritional status. We compared 2 ORS containing 50 mmol/L sodium with the same osmolarity and energy content. The control (C) solution contained only carbohydrates while the tested (G) solution contained 60 mmol/L glutamine. We included 44 infants aged 1 to 9 months with acute diarrhea and more than 5% dehydration. They received 200ml/kg of either C or G solution by continuous intra-gastric tube-feeding during a 24 hour period. Casein hydrolysate (Pregestimil®) was then introduced in increasing amounts over a 96h period, and adding the same ORS up to 150ml/kg/day as total intake. The efficacy as regards rehydration, recovery of diarrhea and nutritional status was studied. Serum glutamine, ammonia and urea levels were measured, as well as, urine nitrogen output. Our results showed that in group G not only did the watery stools end earlier (12,3±3,28h vs 39,2±8,2 p = 0.007), but the first normal stool occurred also earlier (33,2±4,6 vs 52,9±8,6 p = 0.04). The presence of glucose in the stools was rarely observed after 48h in group G (p = 0.04) as compared to group C. In group C the insulin growth factor 1 (IGF1), a marker of nutritional status, fell but it remained stable in group G (p = 0.004). Both ORS had the same efficacy on rehydration and normalisation of blood sodium, potassium and proteins. The glutamine blood level was increased by 60% in group G, the urea level fell more slowly in group G (p <0.0001) while the ammonia level was higher but remained in the normal range in group G (p=0.01). This study suggests that the new ORS containing glutamine is effective in the recovery and nutritional status of diarrheic infants. The low osmolarity in the 2 solutions and the low amount of sodium chloride may explain the results of our study as compared to the single, non conclusive study, promoted by the WHO and published in 1994. This new solution could be of clinical interest when treating children with acute diarrhea, especially in developing countries or in children suffering from malnutrition.

Limitations of the Various Methods for Collecting Dietary Intake Data

The dietary intake of population groups may be assessed using food consumption level estimates on a national basis and household food surveys. These may be useful for monitoring secular trends and geographical differences with stable and well-documented populations, but analytical studies of diet and health require data on individuals. Assessment techniques designed to assess the diet of individuals ranging from records with weights of food to questionnaires and biological markers have been critically reviewed in order to assess the accuracy of each. Quantitative estimates of the errors involved will be given. For example, the co-efficients of variation of differences incurred from asking subjects to estimate the weight of food portions, rather than weighing them, may regularly be in the 50% range for foods and 20% for nutrients. A variety of studies suggests that the co-efficients of differences in nutrient intake estimated over 1 day from the 24-hour recall method when compared with observed intakes ranged from 4 to 400%. These errors are believed to be random, and precision can be improved by increasing the numbers of observations on each individual or by increasing the numbers of individuals within each group. However, a substantial loss of power is incurred with errors of this magnitude. A more serious potential source of error is systematic bias due either to differences between different methods of dietary assessment or from deliberate over- or underreporting by the subjects themselves. Studies with the doubly labelled water technique have suggested that substantial underrecording of food intake can occur both in free-living individuals and in athletes. 24-hour urine nitrogen can be used to validate dietary assessments in individuals in nitrogen balance, and on-going studies in Cambridge show that within a group, underreporting occurs in specific individuals rather than in the group as a whole. Independent methods of validating dietary assessments, such as the doubly labelled water technique or the 24-hour urine nitrogen output, must be included in any study of free-living individuals.

Effect of Restricted Water Intake on Urine Nitrogen Output in Man on a Low Calorie Diet Devoid of Protein

Effect of Restricted Water Intake on Urine Nitrogen Output in Man on a Low Calorie Diet Devoid of Protein

Effect of restricted water intake on urine nitrogen output in man on a low calorie diet devoid of protein.

Urine nitrogen was measured in three groups of young men receiving, respectively, daily water allowances of 900 ml, 1800 ml and unrestricted quantity. Food was restricted to 1000 Cal. of carbohydrates, 4.5 gm of NaCl and vitamins. The men were required to expend about 120 Cal. daily in walking. The daily urine nitrogen output at the 5th experimental day (adjusted to 70 kg body weight) averaged 9.4 gm for the men on 900 ml of water, 7.1 gm for the men receiving 1800 ml of water and 5.8 gm for the men on water ad libitum. Nitrogen in the feces was unchanged and that in the sweat was either unchanged, or slightly decreased, by water restriction. The increased nitrogen excretion paralleled the degree of dehydration. An elevation of the blood urea nitrogen was observed by the 5th day of combined food and water restriction in the men on 900 ml of water. On rehydration about 3.4 gm of urea nitrogen was washed out, giving rise to a transient continuation of the high urine nitrogen excretion. The increased nitrogen excretion is considered as a metabolic response to the stress of dehydration, partly related to increased activity of the adrenal cortex glands. This catabolic response does not help the body to economize water, as illustrated by the fact that the men receiving the smallest water allowance excreted more urine water than their mates with a more liberal water allowance, at the day of their maximal dehydration. Submitted on December 19, 1956

Metabolism in the dog before and after splenectomy

SummaryFour dogs in nitrogen equilibrium were studied as to total output of nitrogen in urine and feces, output of ammonia, creatin and creatinin in the urine, and iron and fat in the feces. In each a preliminary control period of seven days was followed by like periods at intervals after splenectomy varying from three days to three months.In three of the four animals the removal of the spleen caused no change in nitrogen metabolism, fat utilization or iron elimination. Two of these animals showed no change in the blood picture and the third only a slight non-progressive anemia. A fourth animal which developed eventually a moderately severe anemia showed slight loss of weight, a disturbance of nitrogen balance and of creatin-creatinin partition and an increased elimination of iron.The following conclusions are reached: (1) that the removal of the normal spleen in an animal which remains otherwise normal causes no disturbance of metabolism: (2) that when disturbances of metabolism occur they are in all pro...