bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary tryptophan level and the enzymes of tryptophan NAD pathway
Authors: Satyanarayana U. , Narasinga Rao B. S. 
Published: June 2005

1. Dietary tryptophan was found to regulate the activities of tryptophan oxygenase (EC I. 13.I. 12)and quinolinate phosphoribosyltransferase (EC z.4. 2a) in liver.2. With increasing tryptophan concentration in the diet containing 100 g protein/kg, tryptophan oxygenase activity increased while that of quinolinate phosphoribosyltransferase decreased. The response of these enzymes to dietary tryptophan at lower dietary protein level (25 g/kg) was not significant.3. Liver nicotinate phosphoribosyltransferase (EC 2.4.2. 11)activity and kidney picolinate carboxylase (EC 4. I.I. 45) activity were unaltered with different tryptophan concentrations in the diet.4. The response of various biochemical measurements was dependent on the tryptophan intake and the changes were marked below and above the requirement level of tryptophan.5. It is suggested that the urinary excretion of quinolinic acid and N'-methylnicotinamide may be useful in assessing the tryptophan nutritional status and its requirement.
Nutritional evaluation of the germ meal and its protein isolate obtained from the carob seed (Ceratonia siliqua) in the rat
Authors: Drouliscos N. J. , Malefaki Vastliki 
Published: June 2005

1. Evaluation of the germ meal (CGM) of carob seed (Ceratonia siliqua) and its protein isolate was carried out with weanling rats. Comparisons were made with casein, soya-bean meal, whole defatted egg and a soya-bean protein isolate (Promine-D) as protein sources. The growth-promoting effects and certain biological indices were evaluated using the protein efficiency ratio (PER), biological value (BV) and net protein utilization (NPU) bioassay procedures.2. The unsupplemented CGM had a PER of 1.66 ± 0.09 and an NPU of 0.58 ± 0.013. Addition of DL-methionine at 4, 8 and 12 g/kg diet resulted in a PER of 1.95 ± 0.11, 2.01 ± 0.11 and 1.90 ± 0.11 respectively. The corresponding BV values were 0.80 ± 0.003, 0.78 ± 0.015 and 0.74 ± 0.011, and those for NPU 0.69 ± 0.013, 0.66 ± 0.026 and 0.63 ± 0.020 respectively. The addition of amino acids improved the PER (2.24–2.59), BV (0.78–0.79) and NPU (0.71–0.73) values.3. The BV and NPU assays for the unsupplemented carob germ isolate were low (BV 0.36 ± 0.016, NPU 0.35 ± 0.015). Supplementation with amino acids resulted in a positive increase with values of 0.66 ± 0.013 and 0.64 ± 0.013 for BV and NPU respectively.
The effects of dietary sucrose and the concentrations of plasma urea and rumen ammonia on the degradation of urea in the gastrointestinal tract of cattle
Authors: Kennedy P. M. 
Published: June 2005

1. The rates of entry of urea into plasma, of urea degradation in the gastrointestinal tract, and the partition of that degradation between the rumen and post-ruminal tract were determined by use of [14C]urea and NaH14CO3 in Hereford steers receiving hay diets with or without sucrose. The concentrations of plasma urea and rumen ammonia were varied by infusions of urea into the rumen or abomasum.2. For all diets, plasma urea concentration was related to urea entry rate, to degradation of urea in the whole gastrointestinal tract, and to its degradation in the post-ruminal tract, but the relationship with its degradation in the rumen was poor.3. Degradation of urea in the rumen was related in a multiple regression in a curvilinear manner in three groups of diets (pasture-hay alone, pasture-hay–lucerne (Medicago sativa) mixtures, diets with sucrose), and negatively to rumen ammonia concentration for pasture-hay diets, and diets with sucrose.4. Ruminal clearance of urea (rate of urea degradation per plasma urea concentration) was negatively related to the rumen ammonia concentration for steers given diets with sucrose, of pasture-hay with or without urea infusions. Provision of sucrose in the diet significantly increased clearance.5. Enhanced urea degradation in the rumen associated with dietary sucrose supplements accounted for 0.4 of additional microbial N synthesis in the rumen.6. The partition of transfer of urea to the rumen via saliva and through the rumen wall is discussed.
Cold exposure and mammary glucose metabolism in thelactating goat
Authors: Faulkner A. , Thomson E. M. , Bassett J. M. , Thomsont G. E. 
Published: June 2005

1. [U-14C]glucose was infused intravenously into conscious lactating goats exposed to thermoneutral or cold environments for a total of 24 h. The irreversible loss of glucose from the whole body and uptake of glucose by the mammary gland was measured and glucose utilization in the udder was studied by measuring the incorporation of radioactivity into carbon dioxide in mammary venous blood, into milk lactose and milk triglyceride-glycerol.2. Exposure to cold increased the circulating level of glucose and slightly, though not significantly, increased the non-mammary irreversible loss of glucose.3. The extraction of glucose from the circulation by the udder fell, the secretion of lactose by the udder also fell and this correlated closely with the reduced secretion of milk in the cold.4. Simultaneous measurements of the concentrations of insulin, growth hormone and corticosteroids in the arterial plasma were made.5. The plasma concentration of corticosteroids increased significantly in the cold.6. It is concluded that reduced glucose uptake and lactose synthesis by the udder are important factors which reduce milk secretion during cold exposure.
Refection in rats fed on a sucrose-based, riboflavin-deficient diet
Authors: Prentice A. M. , Bates C. J. 
Published: June 2005

1. Refection, resulting in an increased supply of riboflavin to riboflavin-deficient rats through coprophagy, was demonstrated on a sucrose-based diet when sensitive biochemical tests of riboflavin status were employed: these included measurements of NAD(P)H2:glutathione oxidoreductase (EC1.6.4.2); succinate:(acceptor) oxidoreductase (EC1.3.99.1) and NADH:(acceptor) oxidoreductase (EC1.6.99.3).2. The use of tail-cups to eliminate coprophagy, and hence refection, resulted in a more rapid and reproducible progress into severe deficiency.3. The occurrence of refection on a sucrose-based diet may account for hitherto unexplained differences between previous publications on the biochemical effects of riboflavin deficiency.
Endocrine control of energy metabolism in the cow: the effect on milk yield and levels of some blood constituents of injecting growth hormone and growth hormone fragments
Authors: Bines J. A. , Hart I. C. , Morant S. V. 
Published: June 2005

1. Circulating concentrations of some hormones and metabolites and nitrogen balance were measured in lactating beef and dairy cows given daily injections of growth hormone (GH) and were compared to values before injection. Changes in milk yield and composition were recorded in these cows and in additional cows injected with GH fragments.2. GH, but not GH fragments, raised milk yield while milk composition did not change. GH injection caused a large, rapid increase in the level of the hormone in blood and slower, smaller increases in the concentrations of insulin, prolactin and thyroxine. Blood metabolite levels were unaltered except for a rise in glucose concentration in beef cows during GH injection and a fall in 3-hydroxybutyrate concentration in the same cows after the injections ceased. An increase in N output in milk was partly balanced by a reduction in urinary N so that N retention did not change significantly.3. GH caused a reduction in food intake in the beef cows.4. The results are discussed in relation to control of partition of nutrients in the lactating cow, where GH is considered to play an important role. It was concluded that this role may be in increasing the supply of energy metabolites for milk synthesis, rather than a direct effect on the activity of the mammary gland.
The effect of feeding sugar-beet silage and non-protein-N on rumen and blood metabolites in bulls
Authors: Kulasek G. , Barej W. , Leontowicz Hanna , Krasicka Barbara , Chomyszyn M. , Zawitkowski J. 
Published: June 2005

1. The purpose of the experiments was to determine certain properties of the metabolism of nitrogen compounds and carbohydrates in the rumen and tissues of growing bulls which were given either a diet containing sugar-beet silage, a urea-mineral preparation and hay or a control diet with maize silage, ground barley and hay. Daily rations were given in two equal portions twice daily at 07.00 hours and 13.00 hours. The experiment lasted 182 d.2. The experimental diet containing 0.54 g urea and 5.0 g saccharose/kg body-weight did not cause any symptoms of toxicity in the animals although there were large changes in the concentration of metabolites in the forestomach. The lowest pH (6.2–6.4) in the rumen of animals in the experimental group was observed 1.5 h after feeding. At the same time the highest level of lactic acid was observed, but the highest level of volatile fatty acids (VFA) was observed 3 h after feeding. Although there was a large increase in ammonia in the rumen contents (approximately 20 mmol/l at 1.5 h after feeding) an increase in the blood level of ammonia was not observed.3. A lower level of acetic acid and higher level of butyric acid and valeric acid were observed in the rumen of animals given sugar-beet silage than in animals given maize silage and ground barley. Non-glucogenic ratio of VFA in the rumen of bulls after feeding the experimental diet was approximately 3.5 while on the control diet the value was considerably higher.4. The causes of the low concentration of glucose in the blood and changes in other metabolites in the blood of experimental animals are discussed.5. Average daily gains were higher (P≤ 0.05) in both groups of bulls given a diet containing sugar-beet silage and NPN (1087 and 1043 g/d) than with the control diet (887 g/d). Changes in the concentration of metabolites in the rumen contents and blood of sugar-beet-silage-fed bulls confirmed the possibility of effective addition of urea in an amount corresponding to 50% of the N content and also indicated good utilization of the energy in this diet.
Studies on diurnal variations of heat production and the effective lower critical temperature of early-weaned pigs under commercial conditions of feeding and management
Authors: McCracken K. J. , Caldwell B. J. 
Published: June 2005

1. The heat production of groups of pigs, weaned at 10 d of age, was determined in an open-circuit respiration chamber at various ages between 10 and 33 d at temperatures above and below the lower critical temperature (Tcl).2. The heat production was lowest on the second or third day post weaning when pigs were given feed increasing by 25 g/pig per d from day 2. There was a marked diurnal pattern in heat production, the lowest values being recorded between 24.00 and 08.00 h.3. The mean thermal conductance (H/ΔT, kJ/h per m2 per °ΔT, where His total heat production, m2 is the surface area calculated as 0.097 W kg0.633 (Brody, 1945) and °ΔTis the difference between rectal temperature, taken as 39°, and air temperature) below Tcl was calculated as 18.0, 16.9, 18.5 and 21.2 respectively at 10, 17, 24 and 31 d of age. Maximum values of H/ΔT obtained during feeding periods were. on average, 4.5 kJ/h per me per °ΔT higher than the mean values.4. The maximum value for Tcl during the immediate post-weaning period was 25.9°. The mean Tcl at 17, 24 and 31 d were respectively 21.7, 18.4 and 18.6° for pigs fed almost to appetite.
The influence of molybdenum on the copper metabolism of the rat at different Cu levels of the diet
Authors: Nederbragt H. 
Published: June 2005

1. Male WAG/Cpb inbred rats fed on rations with approximately 1–5rng copper/kg (deficient), 6.0 mg Cu/kg (adequate) and 25.0 mg Cu/kg (excess) were supplemented with varying amounts of molybdenum (0, 50, 150 and 500 mg/kg diet) and the effect on the Cu concentration of blood, plasma, liver and kidney, the caeruloplasmin activity of plasma and the Mo concentration of liver and kidney were studied.2. Mo increased the Cu concentration of blood, plasma, liver and kidney and the Mo concentration of liver and kidney.3. In the plasma of Mo-supplemented rats the presence of a Cu-containing fraction was demonstrated, the Cu of which did not react with dithiocarbamate and was not related to caeruloplasmin. The Cu in this fraction was not able to increase the caeruloplasmin activity in the plasma of Cu-deficient Mo-supplemented rats. The Cu concentration of the erythrocytes did not seem to have been increased by the Mo treatment.4. When compared to Cu-adequate rats the effect of Mo on the Cu distribution was reduced both by Cu deficiency and Cu excess. This decreased effect of Mo was explained by reduced uptake or retention of MO in the body as observed in the liver and kidney.
The effect of iron-deficiency anaemia on two indices of nutritional status, prealbumin and transferrin
Authors: Delpeuch F. , Cornu A. , Chevalier P. 
Published: June 2005

1. Serum prealbumin, transferrin and iron concentrations were measured in ninety-two north Cameroonian children under 5 years of age. The results were grouped according to the blood haemoglobin concentration range in order to show the interactions of anaemia with prealbumin and transferrin concentrations.2. Transferrin concentration showed a significant negative correlation with serum Fe and percentage saturation of transferrin values. Prealbumin concentration showed a significant direct correlation with haemoglobin but did not correlate with either serum Fe or percentage saturation of transferrin.3. It is concluded that in regions where Fe-deficiency anaemia is endemic transferrin concentration may be of little value in determining nutritional status. On the contrary, prealbumin seems to be more useful.
Estimation of in vivo digestibility with the laying hen by an in vitro method using the intestinal fluid of the pig
Authors: Sakamoto K. , Asano T. , Furuya S. , Takahashi S. 
Published: June 2005

1. Dry matter and crude protein (nitrogen × 6.25) digestibility of four poultry diets determined by an in vitro method using the intestinal fluid of pigs was significantly correlated with corresponding in vivo digestibility values obtained with hens.2. The intestinal fluid could be lyophilized and stored for at least 35 d without losing its activity on digestion.
The early changes in retinol-binding protein and prealbumin concentrations in plasma of protein–energy malnourished children after treatment with retinol and an improved diet
Authors: Large Suzanne , Neal G. , Glover J. , Thanangkul O. , Olson R. E. 
Published: June 2005

1. Changes in total retinol-binding protein (RBP), the holoprotein (holoRBP) and prealbumin (PA) concentrations have been monitored in plasma of thirty protein- and vitamin A-deficient preschool children from within a few hours up to 7 weeks after treatment with retinol and a good-quality protein diet.2. The children were classified into groups according to nutritional status as having either kwashiorkor, marasmus-kwashiorkor or marasmus, and given formula diets whose protein and energy contents increased stepwise from 1 g and 105 kJ/kg body-weight respectively up to 4 g and 733 kJ/kg body-weight after 4 weeks. Retinol was administered in the forms of retinyl palmitate either orally or intramuscularly.3. PA and total RBP were determined by electroimmunoassay procedures and the holoRBP by its fluorescence after separation from other plasma proteins.4. RBP in plasma of the vitamin A-deficient child is largely denatured and incapable of binding administered retinol, which must first be taken up by the liver before native holoRBP is released. An increased pool of native apoprotein accumulates in the liver during vitamin A deficiency which is released into plasma quickly after retinol uptake to form peak concentrations of total and holoRBP approximately 3 h after dosing intramuscularly and 6 h orally.5. The accumulated pool of RBP was highest in livers from the marasmus group and lowest in those from the kwashiorkor group, reflecting their relative capacities to synthesize plasma proteins.6. The mean plasma concentrations of total and holoRBP for the various groups were minimal 24–48 h after dosing with retinol and then improved almost linearly over the following week.7. Mean plasma PA concentrations of the various groups on admission were also in order of the severity of their malnutrition. There was little or no change in this protein concentration over the first 24 h after dosing with retinol, but thereafter the mean values rose almost linearly over 2 weeks. Albumin on the other hand changed little during the first week. The results show that PA is the more sensitive measurement of protein nutritional status.
Phosphopeptides and soluble calcium in the small intestine of rats given a casein diet
Authors: Lee Yeon Sook , Noguchi T. , Naito H. 
Published: June 2005

1. Semi-synthetic diets containing 200 g protein/kg were meal-fed for 1.5 h to groups of rats. The contents of the whole small intestinal tract were collected and the amount of soluble calcium was determined.2. In the rats given 200 g casein/kg diet, formation of a fraction containing macrophosphopeptide in the small intestine was confirmed by gelfiltration of the intestinal contents on Sephadex G-25. However, this macrophosphopeptide fraction was not found when casein alone was fed.3. In the intestinal contents at 2.5 h after ingestion, the amounts of both soluble Ca and phosphorus were significantly higher in rats fed the casein diet than in those fed diets containing egg albumin, isolated soyabean protein or an amino acid mixture. However, the amount of insoluble Ca was least in rats fed the casein diet.
A simple procedure using35S incorporation for the measurement of microbial and undegraded food protein in ruminant digesta
Authors: Mathers J. C. , Miller E. L. 
Published: June 2005

A simple procedure using35S incorporation for the measurement of microbial protein in abomasal or duodenal digesta of ruminants was developed and tested.Microbial protein synthesized in the rumen was labelled with35S by intraruminal infusion of35SO4and a microbial fraction was isolated by differential centrifugation.35S not bound by micro-organisms and present as inorganic35S in whole digesta and in microbial fractions was oxidized to35SO4and the samples were brought into solution by acid-hydrolysis.35SO4was precipitated as Ba35SO4.The proportion of microbial non-ammonia-nitrogen (NAN) in digesta NAN was determined as35S:NAN (digesta) ÷35S:NAN (microbial).In sheep offered grass nuts at maintenance level of feeding, 48% of NAN flowing through the abomasum was of microbial origin. NAN flow to the small intestine was estimated using chromic oxide as a marker and it was calculated that 49% of the grass N was degraded in the rumen.
Effects of withdrawal of copper sulphate from the diet of the mature domestic fowl with special reference to production and tissue mineral content
Authors: Stevenson Mary H , Jackson N. 
Published: June 2005

1. Cereal-based diets containing 0, 500, 1000 or 2000 mg added copper/kg were offered ad lib. to laying hens for 8 weeks. All the hens were subsequently offered the control diet (no added Cu, 7.5 mg Cu/kg).2. Hens from each treatment were killed at 0, 2, 4, 6 and 8 weeks after removal of the Cu-supplemented diets. Records were kept of body-weight, food consumption and egg production.3. After slaughter, blood haemoglobin, packed cell volume, serum Cu and aspartate aminotransferase (AAT; EC 2.6.1.1) were assayed. The liver, kidneys, oviduct, ovary, gizzard, caeca and bile duct were weighed.4. Mean Cu, zinc and iron concentration of liver, kidneys and caecal contents were determined.5. The adverse effects of Cu on body-weight, food intake, egg production and liver, oviduct, ovary, gizzard and bile weights were rapidly reversed by removal of added Cu from the diets.6. Greatly enhanced liver Cu concentration resulted from feeding the high-Cu diets but this effect was rapidly reversed on removal of added Cu from the diets. Liver Fe concentration showed a less marked but similar effect.7. The Cu concentration of caecal contents was increased by Cu supplementation and rapidly reduced after withdrawal of the Cu-containing diets.
Energy expenditure of male farmers in dry and rainy seasons in Upper-Volta
Authors: Brun Thierry , Bleiberg Fanny , Goihman Samuel 
Published: June 2005

1. Thirty Mossi male farmers from Upper-Volta were investigated, twenty-three in the dry season (March-April) and sixteen in the rainy season (July-August), eight of them being studied twice. A 48 htime-and-motion study was carried out and the daily energy expenditure was computed.2. The mean height was 1.70 m and the mean weight 58.5 kg. The average percentage of body fat calculated from skinfold thickness was 10.3. During the dry season the subjects could be classified as very moderately active with an energy output of 10.1 MJ (2410 kcal)/d. By contrast, with an energy expenditure of 14.4 MJ (3460 kcal)/d, they were considered as exceptionally active in July-August when performing the agricultural work.4. In this study we measured the intensity of physical work in a society where human labour is still the main tool of production. The determination of seasonal variations in energy expenditure may be useful to assess the nutritional requirements in arid zones of West Africa.
An examination of factors which may affect the water holding capacity of dietary fibre
Authors: Robertson J. A. , Eastwood M. A. 
Published: June 2005

1. Dietary fibre has a water holding capacity (WHC) and this is a function of the fibre source and method of measurement. Water can be associated with fibre either as trapped water or bound water. This makes it difficult to predict the ability of fibre to influence stool weight in humans.2. Examination of various fibre concentrates for chemical composition, as neutral detergent fibre (NDF), acid detergent fibre (ADF) and lignin; structure, by scanning electron microscopy; WHC, by centrifugation, suggests that WHC is more a function of fibre structure than chemical composition. Cereal fibre and vegetable fibre have a different chemical composition and are structurally very distinct. Structure is also dependent on the method of fibre preparation.3. Measurement of WHC by centrifugation gives an estimate of the water which can be bound and also trapped by the fibre. The amount of trapped water will depend on the structure of the fibre whereas bound water will depend on the chemical composition.
Energy intakes on sledging expeditions
Authors: Campbell I. T. 
Published: June 2005

1. Previous measurements of energy intake on sledging journeys in Antarctica have given a mean intake of 14.2 MJ (Acheson, 1974; Campbell, 1975), markedly lower than values reported earlier (see Edholm & Goldsmith, 1966). The technique used (individual weighed-diet survey) was more detailed and could be assumed to be more accurate than most of the earlier work where intakes had been largely inferred from the known energy content of food boxes. In the present study an individual weighed-diet survey was carried out on male subjects during a summer manhauling journey on the east coast of Greenland.2. Mean daily energy intake of six subjects over 33 d travelling was 16.5 MJ. Mean weight loss was 2.3 kg, probably accounted for entirely by fat loss. Weight loss occurred despite the presence of excess food. Mean daily energy intake rose gradually but persistently over the 5 weeks of the journey despite a constant level of activity and to 20.1 MJ during the 4 d rest at the end of the journey.3. Intakes were thus higher than those found in the earlier Antarctic studies (Acheson, 1974; Campbell, 1975) but not as high as intakes reported previously (see Edholm & Goldsmith, 1966). The fact that weight loss occurred despite the presence of excess food was ascribed to the monotonous nature of the diet. The fact that energy intake rose persistently over the 5-week study period may imply that a new state of balance of intake and expenditure was reached.