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Dietary amino acid requirements of gestating sows vary depending on genetic strain, energy intake, body weight, and other factors. Estimation of amino acid requirements for gestating sows in a defined situation should be directed toward achieving a high rate of protein accretion and a modest rate of fat accretion. More information is needed to set target accretion rates precisely. A simple mathematical model was developed with the limited objectives of 1) aiding in understanding the interactions among energy intake, amino acid intake, protein accretion potential, and body weight in affecting the amount of body protein and fat accreted by pregnant sows and 2) providing general guidelines for feeding programs. Predictions from the model suggest that the daily lysine requirement varies markedly with variation in ME intake but that the requirement as a percentage of the diet is more stable as ME intake varies. At moderate ME intake, the lysine requirement seems greater during late gestation than earlier. The lysine requirement of heavy sows is less than that of light gilts at a similar ME intake, and this offers opportunity for modest cost savings in pork production. A compromise is necessary between the goals of a high rate of protein accretion and a modest rate of fat accretion. It seems that a sow's potential protein accretion rate is rarely limiting.

Seventy-two gilts were used to determine the effect of reducing excess amino acid intake on growing-finishing pig performance. Separate diets were formulated for the growing (20 to 55 kg BW) and finishing (55 to 100 kg BW) periods. For each period, three diets were formulated that varied in total crude protein level and contained similar levels of digestible ideal protein. Crystalline amino acids were added to the low protein diets to overcome potential deficiencies. The grower diets contained .66% apparent ileal digestible lysine and contained 16.6, 15.0, and 13.0% CP, respectively; for the finisher diets, these values were .55% digestible lysine and 14.2, 12.8, and 11.0% CP, respectively. Amino acid analyses and a separate digestibility trial were conducted to confirm digestible amino acid levels in the dietary ingredients. During the growing and the overall growing-finishing period, daily gain, feed intake, and gain:feed were not affected (P.10) by dietary treatment. Daily gain tended to be lower (P = .06) and gain:feed was poorer (P.05) for pigs fed the 11.0% CP diet during the finishing phase. Although backfat thickness tended to be greater (P = .07) for pigs fed the lower-CP diet, estimated carcass lean yield was not affected (P.10) by dietary treatment. Results of this study show that dietary CP can be reduced to 13% in the growing and 12.8% in the finishing diets of pigs as long as crystalline amino acids are added to match the apparent ileal digestible amino acid ratios in an assumed ideal protein.

The amount of metabolic fecal amino acids (MFAA) in dependence on the amino acid intake was determined for graded maize rations with 15N-labelled rats and the quota of labelled endogenous amino acids in faeces was calculated according to the isotope dilution method. The excretion of amino acids and MFAA in faeces are described as functions of the amino acid intake for 17 amino acids and regressively calculated. For all 17 amino acids investigated, there was a more or less steep increase of MFAA according to an increasing amino acid intake. In contrast to MFAA in N-free feeding, MFAA in feeding with pure maize (16.5% crude protein) increase to the 2- to 4.5-fold value. The thesis of the constancy of the excretion of MFAA can consequently be no longer maintained. The true digestibility according to the conventional method is, on an average of all amino acids, 7.3 units below the one ascertained according to the 15N-isotope method. For the limiting amino acids lysine and threonine the difference is biggest (23 resp. 17 units). Tryptophane as first limiting amino acid could not be determined. The true digestibility of nearly all amino acids ascertained for maize according to the isotope method is above 90%. For the limiting amino acids the expenditure resp. the loss of endogenous amino acids is biggest.

Parenteral feeding of preterm infants has been accepted as an alternative form of nutrition in those infants unable to accept oral feeding. The amount of amino acid nitrogen and the composition of the amino acid solution to be used, however, have not yet been defined. The amino acid intake and the plasma amino acid concentration of three groups of preterm infants were compared. Twenty-three infants were fed parenterally. Of these, 16 were studied during the first week of life (group I) and 7 during the second week (group II). A control group of 9 infants fed with oral formula was also studied in the second week (group III). In general, plasma amino acid concentrations in the parenterally fed groups were higher than in the orally fed group, in spite of a lower intake. Comparison of the amino acid intake of groups I and II relative to group III, with the plasma amino acid concentrations of groups I and II relative to group III, revealed a rather constant ratio with the exception of tyrosine and aspartic acid, where higher values were found. It is concluded that further increase in the amino acid nitrogen in parenteral feeding of preterm infants requires a more adapted preparation.

The objective of the present investigation was to investigate the nature of the blood amino acid response with amino acid intake in newborn infants. Forty-nine newborn infants of 640 to 4020 g birth weight and 26 to 40 weeks gestational age were placed on one of the following regimes within 48 hr of birth: intravenous dextrose with intravenous feeding of three levels of crystalline amino acid mixture, or of one level of casein hydrolysate, or with oral feeding of two levels of milk formula. Blood amino acid levels at 132 hr after feeding of graded levels of the intravenous amino acid solution were evaluated by regression analyses and com- pared to blood levels when casein hydrolysate was fed intravenously or milk formula was fed orally. At low levels of amino acid intake, such as were achieved with formula feeding, blood levels were relatively unchanged. However, with higher intakes, as were obtained with intrave- nous feedings, blood levels increased at rates which could be defined for each amino acid. This observation suggests that if the composition and rate of delivery of an amino acid solution is known, blood levels may be predicted. Am. J. Clin. Nutr. 30: 1110-1121, 1977.

Summary It appears that neonates, especially those with very low birthweights, may be at especially high risk of developing cholestasis associated with total parenteral nutrition (TPN). Within 2 weeks of starting intravenous alimentation, it would appear highly desirable to be able to start at least small enteral feedings to interrupt the physiology of fasting. Such feedings may not have to be of much nutritional benefit to improve cholestasis. Calorie and amino acid intake should be limited to the requirements of the infant being treated. Whether protection of the TPN infusate from light is of benefit remains to be determined. Drug therapies for TPN-associated cholestasis of infancy have not been proven safe or effective. Additional investigations to further clarify the pathogenesis of this syndrome, and clinical studies of prophylaxis and therapy, are needed to enhance our ability to provide nutritionally effective and metabolically safe parenteral nutrition.

Weanling rats were offered a choice of two diets, varying only in lysine content. The preference test was performed between a 20% gluten diet supplemented with 0.5% lysine HCl and a lysine-deficient amino acid mixture, 20% gluten or 20% gluten plus 0.2% lysine HCl diet, and was done between a 20% gluten diet and a 20% gluten diet containing 3, 5 or 7% lysine · HCl. Weight gain and food intake were not significantly different among all the self-selecting groups, and these values were almost the same as those in rats fed only the 20% gluten supplemented 0.5% lysine · HCl diet which obtained maximal growth. The lysine intake of the combination groups ranged from 67 to 240 mg per day (0.62-2.35% of consumed food). It was demonstrated that rats exhibit a definite ability to regulate lysine intake, and they select sufficient lysine to meet their requirements for this amino acid. The self-selection technique may be useful as a method to determine the requirements for amino acids.

Rats with bilateral lesions of the anterior prepyriform cortex or medial amygdala demonstrate attenuated behavioral sensitivity to a dietary threonine-imbalance. While rats with medial amygdaloid lesions demonstrate an attenuated ability to acquire taste-avoidances, such a deficit is not found in rats with lesions of the anterior prepyriform cortex. The effect of anterior prepyriform and medial amygdaloid lesions on behavioral sensitivity to dietary amino acid imbalances is discussed in terms of the probable roles played by these areas in amino acid intake control.

Renal adaptation to altered dietary sulfur amino acid intake occurs at luminal brushborder membrane. The β-amino acid transport capabilities of rat renal epithelium were assessed using brushborder membrane vesicles (BBMV). Taurine, a metabolically inert sulfur-containing amino acid, was studied with emphasis on the renal adaptation to dietary sulfur amino acid alteration. Three isoproteinic diets were given to Sprague-Dawley rats: low-sulfur-amino-acid diet (LTD), normal-sulfuramino-acid diet (NTD), and high-taurine diet (HTD). Our studies demonstrated that taurine is actively transported into membrane vesicles by a sodium-dependent transport system. This transport is enhanced by hyperpolarization with valinomycin and decreased by dissipation of the sodium gradient by gramicidin. On LTD (compared to NTD), plasma taurine, urinary taurine, and fractional excretion of taurine were reduced. On HTD (compared to NTD), plasma taurine, urinary taurine, and fractional excretion of taurine were elevated. In vitro studies in BBMV from NTD animals revealed a K m of 40 µM and V max of 102 pmoles/mg protein/30sec. Other β-amino acids significantly inhibited BBMV taurine accumulation. BBMV taurine uptake was enhanced after LTD (compared to NTD) and diminished after HTD (compared to NTD). These studies indicate that a renal adaptation to dietary alterations in sulfur-containing amino acids occurs and that the luminal brushborder membrane participates in the adaptation. Renal adaptative mechanisms to dietary change may serve to help conserve amino acids during deprivation and to excrete amino acids during periods of excess. L'adaptation renale a un apport alimentaire altere en acides amines soufres se produit dans la bordure en brosse luminale. Les capacites de transport des acides β-amines de l'epithelium renal de rat ont ete etudiees en utilisant des vesicules de bordure en brosse (BBMV). La taurine, un acide amine contenant du soufre, metaboliquement inerte, a ete etudiee avec un interet particulier pour l'adaptation renale a une alteration alimentaire en acides amines soufres. Trois regimes isoproteiques ont ete donnes a des rats Sprague-Dawley: un regime pauvre en acides amines soufres (LTD); un regime normal en acides amines soufres (NTD), et un regime riche en taurine (HTD). Nos etudes ont montre que la taurine est activement transportee dans les vesicules membranaires par un systeme de transport sodium dependant. Ce transport est stimule par une hyperpolarisation avec de la valinomycine, et est diminue par dissipation du gradient de sodium par la gramicidine. Avec un LTD (par rapport a un NTD), la taurine plasmatique, la taurine urinaire, et l'excretion fractionnelle de taurine etaient diminuees. Avec on HTD (par rapport au NTD), la taurine plasmatique, la taurine urinaire, et l'excretion fractionnelle de taurine etaient elevees. Des etudes in-vitro sur des BBMV d'animaux en NTD ont revele un K m de 40 µM et une V max de 102 pmoles/mg proteine/30sec. D'autres acides β amines ont significativement inhibe l'accumulation de taurine dans les BBMV. L'entree de taurine dans les BBMV etait stimulee apres LTD (par rapport au NTD) et diminuee apres HTD (par rapport au NTD). Ces etudes indiquent qu'il se produit une adaptation renale a des alterations alimentaires en acides amines contenant du soufre et que la bordure en brosse luminale participe a cette adaptation. Les mecanismes d'adaptation renale aux modifications alimentaires pourraient aider a conserver les acides amines pendant une restriction, et a excreter les acides amines pendant les periodes de surcharge.

A study was undertaken to measure the ability of rats to regulate amino acid intake by means of a self-selection method. Weaning rats were simultaneously offered a choice between a 10% casein diet or a 10% amino acid mixture diet lacking methionine or lysine and a 10% casein diet containing different levels of methionine or lysine over 2 weeks. Weight gain and food consumption of rats allowed a choice between the two diets were much greater than those of animals fed on the fixed diets with high levels of methionine or lysine added, and the self-selecting rats had the ability to take in amounts of methionine or lysine appropriate to meet the requirement. Methionine intakes of self-selecting rats were kept to a relatively narrow range (41--100 mg/day), but lysine intakes of self-selecting rats were wide-ranging (86--300 mg/day). It was demonstrated that methionine or lysine intake is closely regulated in rats given a choice of diets containing varied levels of methionine or lysine.

Three chick growth assays were conducted to investigate the effects of monensin on lysine and arginine utilization in crossbred chicks (New Hampshire × Columbian). Chicks were fed either a low lysine corn-sesame meal diet containing graded increments of crystalline lysine·HCl (Assay 1) or an arginine-deficient casein-dextrose diet (Assay 2) supplemented with graded levels of L-arginine·HCl in the presence or absence of supplemental monensin (121 mg/kg). Based upon analysis by slope-ratio methodology (i.e., gain regressed on supplemental amino acid intake), the efficiency of L-lysine or L-arginine utilization was found to be the same in both monensin-fed and control chicks. In Assay 3, effects of monensin on the lysine-arginine antagonism were studied. Chicks were fed an arginine-deficient casein-dextrose diet supplemented with 1 or 2% L-lysine·acetate in the presence or absence of supplemental monensin. Growth performance was depressed by feeding both levels of supplemental L-lysine·acetate. Monensin had no effect on the magnitude of the growth depression caused by supplemental lysine. These results support the view that neither lysine nor arginine utilization is impaired by feeding monensin.

1. Two experiments are described in which a system of intermittent lighting (15 min light followed by 45 min dark for 15 h, then 15 min light, 30 min dark, 15 min light and 8 h dark) was applied to laying pullets from 37 to 72 weeks of age. A step-up lighting programme was used as a control treatment (8L:16D from 0 to 18 weeks, photoperiod increased by 20 min each week from 18 to 41 weeks, 16L:8D from 41 to 72 weeks of age). 2. Food consumption was reduced by about 5% when intermittent lighting was in use and by 3.8% for the period from 18 to 72 weeks. 3. Rate of lay and egg weight were similar for intermittent lighting and the control treatment, provided that protein content of the diet was adjusted to maintain an adequate amino acid intake. 4. In the second trial 2 stocks, 2 stocking densities confounded with 2 temperatures and 2 types of food trough were used. Each of these factors affected food intake and it was found that more food was saved by intermittent lighting when intake was high and less when it was low. The proportion saved was approximately 5%. 5. Mortality was slightly but not significantly lower in both experiments where intermittent lighting was used. This may indicate that caged pullets are under less stress when intermittent lighting is used.

Twenty-seven infants from 1 day to 9 months of age with severe intractable diarrhea were fed an oral elemental diet (Vivonex) consisting of crystalline amino acids, glucose, electrolytes, and vitamins by continuous nasogastric drip. Complete control of diarrhea was achieved in 24 patients (89 percent) who had an average weight gain of 28 gm/day. Nitrogen balance and plasma amino acids were measured in five patients while they received 2.25 gm of amino acid/kd/day for two weeks and 4.58 gm of amino acid/kg/day for two weeks; the nitrogen balance and weight gain in three patients was proportional to the amino acid intake. When compared to normal levels, plasma amino acids were not appreciably increased with the lower amino acid intake. With the higher amino acid intake, there were significant increases in plasma values for 11 amino acids.

The amino acid nutrition in both of the farming village of coast district and the forestry village of mountain district in Kagoshima Prefecture was compared with each other. The amino acid intake in the both districts was more than all the safe daily intake values suggested by Leverton, Rose and the FAO Committee. Protein scores in the both districts were almost the same, 81-82. The E/T of the two were about 2500, which are far more than that of the reference protein (FAO(1957)), 2020. The values of chemical scores, egg, human milk and cow's milk scores, were just or almost the same in the two districts, 70, 89 and 83-84 respectively, the limiting amino acids of which were sulfur containing amino acids, tryptophan and lysine, respectively. Little correlation was observed between all the above scores and each nutrient intake, and especially no correlation between E/T and each nutrient. In the both districts the positive correlation was observed between both cow's milk score and animal protein ratio or intake, and human milk score and cow's milk score. Also, the negative correlations were observed between both egg score and intake of soybean, and cow's milk score and cereals intake, while in the coast district the positive one was between cow's milk score and intake of fishes.

Synopsis A model which describes the response of groups of laying hens to different levels of amino acid intake is presented. The model is based on the assumption of simple linear relationships between amino acid intake and the output characteristics, egg production and maintenance, for individual birds. The response for a group of birds is then derived as the average of the individual responses. The shape of this flock—response curve depends on seven parameters, namely the mean maximum egg output (Ē max), variation in E max, mean body weight (W), variation in W, the correlation between egg output and body weight, and two constants (a and b) representing respectively the quantities of amino acid required for unit egg output and for maintenance of unit body weight. Three methods of manipulating the model are described. These use (i) a computer simulation procedure; (ii) the exact solution for the model and (iii) some reasonable approximations for practical application. The use of the model for describing e...

Summary In areas where children show undergrown physical development the children are taking less proteins, particularly animal proteins, than those in other areas where children are growing normally. They, therefore, are taking less essential amino acids and their Lysine/Tryptophan ratio is small. By supplying Lysine to the children of undergrown physical development favorable influences were observed on the growth of their weight and height. When Lysine is supplied in the amount to make the Lysine/Tryptophan ratio of their total nutritional intake about 6, the most favorable results in the growth were observed. The amino acid ratio used by F.A.O. for the Protein Score was calculated based on the amino acid minimum requirement for the age group almost grown up. It is considered that the same ratio is not necessarily suitable as the amino acid ratio for the growing stage, especially in the poing where Lysine/Tryptophan ratio is set at 3, which is inapplicable for the children of rice-centered diets. Author explained in this report his opinion on “the growing stage amino acid ratio” and the “pattern”. The order of the amino acids to be supplied and the amounts can be obtained from the each amino acid intake and the growth stage amino acid pattern.

Alterations in the intake of sulfur amino acids (SAA) changes the rat renal brush-border membrane uptake of the beta-amino acid, taurine. A low-SAA diet enhances and a high-taurine diet reduces uptake (Chesney et al., Kidney Int. 24: 588-594, 1983). Neither the low-SAA diet nor the high-taurine diet alters the time course or concentration-dependent accumulation of the sulfur amino acids methionine and cystine or of inorganic sulfate. By contrast the uptake of beta-alanine, another beta-amino acid that competes with taurine, is greater in animals on the low-SAA diet. The high-taurine diet does not change beta-alanine uptake. The plasma levels of taurine are altered by dietary change, but not the values for methionine and cystine. This study indicates that renal adaptation is expressed for beta-alanine, a nonsulfur-containing beta-amino acid. By contrast, methionine, cystine, and sulfate, which participate in a variety of synthetic and conjugative processes, are not conserved by the renal brush-border surface following ingestion of either a low-methionine and -cystine diet or high-taurine diet.

1. A hypothesis, that the optimum amino acid concentration in the diet is not directly proportional to the dietary energy concentration, but changes in inverse proportion to the change in food intake resulting from a change in energy concentration, was tested in three experiments. 2. Response experiments involving the amino acids methionine, lysine and isoleucine were conducted, in each case at three dietary energy concentrations, using a diet dilution and blending technique, thereby ensuring a constant ratio between background amino acids and the first-limiting amino acid in all diets, and also keeping the ratio of amino acids to energy constant as energy varied. 3. A common response curve relating egg output (g/bird d) to amino acid intake (mg/bird d) for each amino acid, fitted by means of the Reading Model, adequately described the response at each of the dietary energy contents. This implies that energy does not influence egg output directly, but only indirectly through its effect on food intake and hence on amino acid intake. 4. Both amino acid and energy concentration significantly influenced food intake. Energy intake was not constant over all dietary energy concentrations, being lower at low energy levels and higher at high energy concentrations. 5. It is concluded that amino acid requirements should not be stated either as percentages or as ratios with energy. Optimum amino acid intakes and energy concentrations should be calculated; the expected food intake should then be predicted, after which the appropriate concentration of nutrients in the diet can be determined.

1. Broilers fed complete diets to 21 but not 44 d of age grew faster with a better efficiency of food utilisation than broilers given a free‐choice selection of the cereal and protein components. 2. When finisher diets, varying in metabolisable energy (ME) and amino acid:ME ratios, were fed at high ambient temperatures (25 to 35 °C) broilers on the free‐choice system selected similar amino acid:ME intake ratios, which were lower than the ratios contained in the complete diets. 3. Differences in broiler performance between 22 and 44 d of age reflected variations in ME rather than amino acid intake.

Information about effects of protein and amino acid intake on carcinogenesis comes mainly from experiments on laboratory animals. In general, tumor formation and tumor growth are retarded in animals consuming proteinor amino acid-deficient diets, but the effects have been attributed mainly to reduced caloric intake or body weight. Nonetheless, some tumors grow well in animals consuming diets that contain levels of protein that are insufficient to meet their nutritional needs. Induction of tumors by chemical carcinogens or procarcinogens may be enhanced or inhibited in animals consuming a diet containing a particular level of protein, depending upon the responses of enzymes that activate or inactivate the specific compound being tested. The feeding of amino acid-deficient diets or amino acid antagonists has been proposed as an adjunct to chemotherapy. Undoubtedly, tumor development and growth can be influenced by the quantity of protein consumed by an animal, but the responses observed with specific tumors and carcinogens may differ. Therefore, it is not possible to draw general conclusions about effects of protein intake on the incidence of cancer or on the process of carcinogenesis.

We have previously shown that there is renal adaptation to alterations in dietary sulfur amino acid intake. While ingesting a low-methionine, low-taurine diet, urinary and plasma taurine concentrations fall, and the accumulation of taurine by collagenaseisolated tubules is greatly enhanced. On a taurine and methionine-supplemented diet (3%, w/w), urinary and plasma taurine values are increased, and accumulation by tubules is diminished. This study was planned to evaluate the effect of fasting on the adaptation to dietary intake change. Rats were given a high-taurine diet (HTD), low-taurine diet (LTD), or a normal diet (NTD) from age 56 to 70 days of life. Half of the rats in each dietary group were fasted for 72 hr and they lost 13 ± 1% of body weight. Plasma taurine values fell in all three fasted groups, and urinary taurine excretion rose in LTD and fell in HTD-fasted animals. Renal cortex taurine fell in all fasted groups, indicative of taurine release. The in vivo tissue distribution ratio rem...

Parenteral feeding of infants is not new. Protein hydrolysates became commercially available some forty years ago, and what might be termed hypoalimentation occurred on a rather smaller scale. However Heird and Winters1 drew attention recently to an infant reported by Helfrick and Abelson in 1944 who was fed intravenously with a mixture of 50 % glucose and 10% casein hydrolysate plus a lipid emulsion for 5 days with apparent weight gain2. A boost was given to parenteral feeding in the 1950s by the development of lipid infusâtes; however this initial boost turned out to be a false result in North America because of their apparent toxicity. During the 1960s parenteral feeding was again practised, more with the infusion of blood products as a last resort, than as a scientific exercise in nutrition.

The amino acid requirement has been investigated by many laboratories since 1931. Authors considered that the requirement was influenced by the protein level of the basal diet and also by the experimental method. In light of those earlier studies, the present study investigated the effect on lysine and methionine requirements by modifying total nitrogen level or essential amino acid level. The result of our study confirmed that when the amino acid requirement for maximum growth was expressed as the dietary percentage, amino acid to total amino acid ratio, and amino acid to total nitrogen ratio, the requirement had changed according to not only essential amino acids but also to nonessential amino acids. Furthermore, we investigated the relationship between amino acid intake and body protein gain, and found that 6.2 mg lysine and 9.0 mg methionine were required for the maintenance of a rat weighing 80 g and 71.6 mg of lysine and 48.8 mg of methionine were required for one gram of body protein gain. The lysine and methionine intakes required for one gram of protein gain were equivalent to 100% and 124% of amino acid contents of body protein, respectively.

Parenteral administration is an abnormal mode of alimentation. With regard to amino acid intake, the normal sequence of events involves metabolic changes in the intestine and screening of the incoming amino acids by the liver before they pass into the peripheral circulation. Once in the systemic plasma, the level of free amino acids is only moderately elevated after each protein meal of normal composition, thus implying that tissue removal of amino acids is adequate to prevent accumulation when the amino acid supply is delivered at a steady rate by way of the intestinal tract.

This study provides data on a number of factors that influence phenylalanine hydroxylase activity in rat liver. By means of a method which utilizes crude liver homogenates, the enzyme activity was determined in rat liver obtained from early embryos to 150-day-old animals. The activity increases with age to a maximum at the young adult age of 50–60 days and then declines. The most rapid increase in activity was found between 18–21 days. The female rat livers show a rapid decline in activity with increasing age, then stabilize at a lower activity than males after maturity is reached. Fasting causes a marked drop in activity, and diets deficient in phenylalanine cause a decrease in the enzyme activity. High casein diets, which increase the phenylalanine and total amino acid intake, had no apparent effect on the level of enzyme activity.

The voluntary preference of the chick was observed for amino acids and energy, while it was fed adequate intakes of all other nutrients. Excessive levels of various amino acids were present in a 13.8% protein synthetic basal diet. In contrast, other chicks fed the basal diet in two parts, namely, soy protein plus amino acids and glucose monohydrate plus amino acids, consumed 2.19% less total amino acids and 3.92% less total energy than the chicks fed the complete basal diet. These chicks utilized significantly less protein per gram of gain than the chicks fed the complete basal diet.

Twenty-five New Zealand White × Californian lactating doe rabbits were used to study the effect of different dietary fibre concentrations on the amino acid contribution of soft faeces to the total amino acid intake. Five isoenergetic diets containing 312, 334, 360, 384, and 412 g/kg neutral-detergent fibre (DM basis) were formulated. All diets were designed to maintain the same amino acid pattern. Soft faeces production showed a trend to increase (P = 0·07) as dietary fibre increased. The content of isoleucine (P < 0·01), glutamic acid, leucine and alanine (P < 0·05) in soft faeces decreased as the dietary fibre increased. A trend to decrease with the increase of dietary fibre was also observed for aspartic acid (P = 0·06), lysine (P = 0·07), methionine and valine (P = 0·1). As a consequence, the soft faeces contribution to the total intake of individual amino acids did not vary with the type of diet. The average contribution of soft faeces to the total amino acid intake for the most limiting amino acids of lactating doe rabbits under practical conditions, methionine, threonine and lysine, were 0·17 , 0·21 and 0·18 g/g, respectively.

Nutritional status and growth were evaluated in 19 children who received home parenteral nutrition(TPN). In 9 pts(age 32±17 SD months, group I), TPN was the only source of nutrition; 10 pts(age 34±16 months, group II) received less TPN and ingested 30 to 70% of their total caloric intake. Energy and amino acid intake from TPN was 81±26 and 110±41% of RDA in group I and 67±15 and 67±29% in Group II. Group I and II had received TPN for 32±10 and 33±17 months, respectively, at evaluation. All pts in Group I and four pts in Group II had short bowel syndrome; five in Group II had pseudo-obstruction syndrome. At the onset of TPN, height and weight were significantly below normal in both groups. At the time of evaluation, group I had normal height (Z scores(Z) = -0.63±2.11) and, for chronological age, normal weight (Z=0.94 ± 2.13), mid-arm circumference (MAC)(Z=-0.47±1.47), mid-arm muscle circumference (MAMC)(Z=0.69±1.0), and triceps skinfold thickness (TSF)(Z=0.40±0.87). In contrast, in Group II patients, height (Z=-1.15±1.02), MAC(Z=-1.53±1.33), and TSF(Z=-1.17±0.64) were significantly below normal, and their weight, MAMC and TSF were lower than in Group I. These data indicate that children undergoing long term TPN can obtain and maintain normal height, weight and other anthropometric parameters of nutritional status. The poorer growth and nutritional status in Group II may be due to an overestimation of the food ingested and absorbed; they need more calories from TPN to normalize growth.