bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative effects of wheat bran and barley husk on nutrient utilization in rats
Authors: Donangelo Carmen M. , Eggum B. O. 
Published: September 2005

1. The present work was undertaken to study comparatively the effect on mineral availability in rats of wheat bran and barley husk when supplying the same amount of dietary fibre (DF). The experiment involved a total of nine dietary treatments including a control group and two series of four groups with increasing amounts of fibre from the two sources (total DF ranging from 42 to 117 gsol;kg dry matter (DM)). Dietary nitrogen concentration was kept constant at 15 g N/kg DM. Zinc concentration of the diets was adjusted to the level provided by the diet with the highest wheat-bran content (21 mg/kg DM) using zinc sulphate. Other minerals were not adjusted.2. Two experiments were performed. In Expt 1 the diets were given to 5-week-old rats during 9 d and apparent absorptions of Zn, calcium and phosphorus and the femur concentrations of Zn, Ca and P were measured. In Expt 2 the diets were given to 9-week-old rats during 12 d. Mineral concentration in femur and total and albumin-bound plasma Zn and availability of plasma Zn for enzyme reactivation were measured.3. In the younger animals, wheat bran depressed significantly the absorption of Zn when providing 40 g DF/kg DM and absorbtion of Ca when providing 80g DF/kg DM. Barley husk depressed significantly both the absorption of Zn and Ca already at 20 g DF/kg DM. Both fibre sources had a more negative effect on Zn than on Ca absorption. Only barley husk had a small negative effect on absorption of P. Phytate did not appear as a major factor affecting mineral absorption in barley husk. All diets containing barley husk had a very low molar ratio, phytate:Zn.4. The age orthe animals influenced the utilization of dietary minerals using femur Concentration as a criterion, particularly in the case of Zn. In the younger animals the decrease in femur Zn with fibre correlated with apparent Zn absorption both with wheat bran (R2 0.986, P < 0.01) and with barley husk (R2 0.996, P < 0.01). In the older animals femur Zn did not change significantly with fibre.5. In the older animals, plasma Zn, albumin-bound plasma Zn and availability of plasma Zn for enzyme reactivation were lowest with the highest addition of wheat bran.
Effect of glucose on fermentation heat in sheep rumen fluid in vitro
Authors: Arieli A. 
Published: September 2005

1. Heat production rate (H) of rumen fluid was measured in a direct calorimeter, Basal H of samples of 15 ml rumen fluid mixed with 45 ml buffer was 0.4 mW/ml rumen fluid.2. Addition of glucose (0.4–6.4 mg/sample) was followed by a dose-dependent increase in H. Maximal H was 1.1 rnW/ml and lasted up to 5 min, returning thereafter to the basal level.3. Expression of fermentation heat (Hf; kJ/mol substrate added) against glucose dose indicated an asymptotic dose response.4. Maximal Hf(at infinite dilution) agreed with stoichiometric calculations whereas minimal Hfsuggested a partial fermentation of the substrate at a high-glucose dose in the rumen environment.
The effect of age, sex and level of intake of dietary fibre from wheat on large-bowel function in thirty healthy subjects
Authors: Stephen Alison M. , Wiggins H. S. , Englyst H. N. , Cole T. J. , Wayman B. J. , Cummings J. H. 
Published: September 2005

1. To evaluate the effect of age, sex and level of intake on the colonic response to wheat fibre, thirty healthy volunteers aged 17–62 years (nineteen men, eleven women) recruited from a local industry, were divided into four groups and given a controlled diet for two 3-week periods. The diet contained white bread during one period or one of four different amounts of bran-enriched wholemeal bread during the other (30, 60, 110, 170 g/d).2. Wide variation was observed between subjects in stool weight on the basal diet and in response to wheat fibre. Stepwise regression analysis showed that the variation in stool weight was significantly related to sex (t4.0, P <0.001) but not to age, height, weight or energy:fibre intakes on the basal diet. Stool weight in men (162(SE 11) g/d) was approximately double that in women (83(SE 11) g/d). Transit time and stool weight were closely related and the effect of sex on stool weight could be explained entirely by differences in transit.4. Faecal carbohydrate excretion increased with the addition of bran mainly due to increased amounts of cellulose and pentose (arabinose+xylose), whilst digestibility of dietary non-starch polysaccharide fell from 77.6 (SE 2.3)% on the white bread diet to 65.6 (SE 2.4)% with the added bran (t 7.4, P < 0.01, n26).5. Faecal pH was more acid in men than in women and was related to methane production. Methane producers had higher faecal pH than non-producers (7.06 (SE 0.1 1) v. 6.65 (SE O.1)), lower stool weight (g/d; 93 (SE 12) v. 156 (SE 13)) and slower transit times (h; 84.6 (SE 11.7) v. 48.6 (SE 6.6)).6. These studies show that, when on similar diets, women have much lower stool weights and slower transit times than men. Furthermore, within the range of amounts of wheat fibre used in this and other published work, stool weight increases in linear proportion to the dose of fibre added to the diet. Methane excretion in breath is associated in this group of subjects with slow transit time and high faecal pH.
Methionine metabolism in isolated perfused livers from rats fed on zinc-deficient and restricted diets
Authors: Duerre John A. , Wallwork James C. 
Published: September 2005

1. Sulphur amino acid metabolism in livers from rats which had been fedad lib. on a restricted diet (malnourished) or a Zn-deficient diet was investigated. Perfusion of normal livers with different amounts of L-methionine revealed that homocysteine was recycled four to five times before being eliminated via the transsulphuration pathway.2. From the perfusion experiments, we found no evidence that any of the enzymes involved in recycling homocysteine back to methionine (methylation pathway) were adversely effected by Zn deficiency or malnutrition.3. The intracellular concentration of cystathionine and S-adenosylmethionine increased in all livers in response to increased concentrations of L-methionine (L-Met) in the perfusate.4. The intracellular concentration of S-adenosylhomocysteine remained the same in all livers regardless of the concentration of perfusate methionine.5. Although homocysteine did not accumulate in the cell, it was excreted into the perfusate. The amount of homocysteine in the perfusate of livers from Zn-deficient rats was higher than eitherad lib. or pair-fed rats.6. The breakdown of homocysteine, via the transsulphuration pathway, was augmented by Zn deficiency. This was apparent from the greater amount of α-ketobutyrate excreted by livers from Zn-deficient rats compared with pair-fed orad lib.-fed controls.7. The increase in metabolism of L-Met, via the transsulphuration pathway, in the livers from Zn-deficient rats appears to reflect the lack of demand for this compound in protein synthesis and methylation reactions (Wallwork & Duerre, 1985).
Effect of selenium deficiency on hydroperoxide-stimulated release of glutathione from isolated perfused liver of rainbow trout (Salmo gairdneri)
Authors: Bell J. G. , Adron J. W. , Cowey C. B. 
Published: September 2005

1. Duplicate groups of rainbow trout (Salmo gairdneri) were each given partially purified diets which were either adequate or depleted in selenium for 40 weeks.2. Although there was no significant difference in weight gain, liver Se concentration was significantly lower in fish given the deficient diet.3. Glutathione (GSH) peroxidase (EC 1. 11. 1. 9) activity was significantly reduced in liver of Se-deficient fish but a differential assay did not indicate the presence of a non-Se-dependent GSH peroxidase activity, although liver GSH S-transferase (EC 2. 5. 1. 18) was significantly increased.4. Perfusion of livers from trout given Se-adequate diets witht-butyl hydroperoxide (BuOOH) or hydrogen peroxide caused an increase in the rate of release of glutathione disulphide (GSSG) into the perfusate.5. Perfusion of livers from Se-deficient trout with BuOOH or H2O2did not result in any change in rate of release of GSSG into the perfusate.6. These findings confirm the absence of any compensatory non-Se-dependent peroxidase activity in Se-depleted trout.
The effect of prolonged dietary supplementation with guar gum on subsequent iron absorption and retention in rats
Authors: Swindell Tina E. , Johnson I. T. 
Published: September 2005

1. The effect of prolonged consumption of guar gum on iron absorption and Fe status was investigated in rats. Experiments with closed loops of duodenum, isolated in siru, were designed to reveal changes in the short-term regulation of duodenal Fe uptake, induced by challenge with low- and high-Fe meals. In separate experiments, the effect of guar gum on the capacity of intact rats to maintain Fe status and to absorb Fe from a test-meal was investigated.2. Male Wistar rats were given either a control, semi-synthetic diet (C) for 21 d or a similar diet containing 100 g guar gum (G)/kg for 27 d. Both diets contained 36 mg Fe/kg. Two subgroups were then challenged with meals containing low-Fe (8 mg/kg) or high-Fe (566 mg/kg), while a third subgroup received a meal of the control diet (36 mg Fe/kg). At intervals of 12, 36, 60 and 84 h after the dietary challenge, the uptake of [59Fe] ferric citrate was measured using closed duodenal loops in situ. All G-supplemented animals absorbed less Fe than their C-fed counterparts. Within group C, animals given the high-Fe challenge had lower absorptions 12, 36 and 60 h later, compared with those given the maintenance diet, whilst those given the low-Fe meal showed much increased uptake 12 and 36 h later. The latter effect was virtually abolished by guar gum.3. In the second experiment, male Wistar rats were fed on the C or G diets containing 8, 15, 20, 26 or 36 mg Fe/kg for approximately 10 weeks ad lib. Fe retention from a starch-sucrose test meal extrinsically labelled with 59Fe was then measured, together with packed cell volume and Fe content of the liver as indices of Fe status. No effect of feeding guar gum on Fe retention nor Fe status at any level of Fe intake was observed.4. It was concluded that feeding guar gum leads to a small reduction in the rate of uptake of Fe in the rat duodenum and to an impairment of the regulation of uptake in response to brief episodes of dietary Fe depletion. However, these changes do not apparently lead to any nutritionally significant reduction in the capacity of the intact animals to absorb Fe and maintain their Fe status.
Contribution of whole-body protein synthesis to basal metabolism in layer and broiler chickens
Authors: Muramatsu T. , Aoyagi Y. , Okumura J. , Tasaki I. 
Published: September 2005

1. The effect of starvation on whole-body protein synthesis and on the contribution of protein synthesis to basal metabolic rate was investigated in young chickens (Expt 1). Strain differences between layer and broiler chickens in whole-body protein synthesis and degradation rates were examined when the birds were starved (Expt 2).2. In Expt 1, 15-d-old White Leghorn male chickens were used, while in Expt 2 Hubbard (broiler) and White Leghorn (layer) male chickens at 14 d of age were used. They were starved for 4 d, and heat production was determined by carcass analysis after 2 and 4 d of starvation. Whole-body protein synthesis rates were measured on 0, 2 and 4 d of starvation (Expt 1), and on 0 and 4 d of starvation (Expt 2).3. The results showed that starving reduced whole-body protein synthesis in terms of fractional synthesis rate and the amount synthesized. Whole-body protein degradation was increased by starvation both in terms of fractional synthesis rate and the amount degraded on a per kg body-weight basis.4. Reduced fractional synthesis rate of protein in the whole body was accounted for by reductions in both protein synthesis per unit RNA and RNA:protein ratio.5. In the fed state, whole-body protein synthesis and degradation rates, whether expressed as fractional rates or amounts per unit body-weight, tended to be higher in layer than in broiler chickens. In the starved state, the difference in the rate of protein synthesis between the two strains virtually disappeared, while the degradation rates were higher in layer than in broiler birds.6. Based on the assumed value of 3.56 kJ/g protein synthesized (Waterlow et al. 1978), the heat associated with whole-body protein synthesis in the starved state was calculated to range from 14 to 17% of the basal metabolic rate with no strain difference between layer and broiler chickens.
Effect of different levels of phosphorus on rumen microbial fermentation and synthesis determined using a continuous culture technique
Authors: Komisarczuk Sylvie , Merry R. J. , McAllan A. B. 
Published: September 2005

1. A continuous culture technique was used to study the phosphorus requirements of rumen micro-organisms. Solutions of artificial saliva containing 120, 80, 40 and 0 mg inorganic phosphorus (Pi)/1 were infused into the reaction vessels previously inoculated with rumen contents, resulting in Piconcentrations in the vessel contents of 48, 28, 4 and < 1 mg/l respectively. Various fermentative and synthetic characteristics were examined.2. In the vessel contents, concentrations of protozoa (about 0.9 x 105/ml) were not significantly affected by piconcentration. Total volatile fatty acids (VFA) produced averaged about 6.83 mmol/h with Pilevels of 48 and 28 mg/l. Reduction in Piconcentrations to 4 and < 1 mg/l resulted in significant reductions in total VFA to approximately 6.25 and 3.75 mmol/h respectively, accompanied by a rise in pH from 6.5 to 7.3. Ammonia-nitrogen values, which averaged about 131 mg/l at the higher Piconcentrations, also increased with the lowest level of Pito about 240 mg/l. ATP concentrations averaged about 14 μmol/l at the highest Piconcentration and fell progressively with each reduction in Piconcentration to a final value of 2.5μmol/1 with the Pilevel < 1 mg/1.3. At Piconcentrations of 48 and 28 mg/l, the digestibilities of xylose, arabinose and cellulose-glucose were maintained at about 0.90, 0.62 and 0.70 g/g input respectively. At lower Pi, concentrations these digestibilities fell significantly and corresponding values at Pi< 1 mg/l were 0.73, 0.41 and 0.31 respectively. Starch digestion was unaffected by Piconcentrations and remained at about 0.90 g/g input.4. The amount of microbial-N synthesized averaged 0.48 g/d and was maintained with Piconcentrations down to 4 mg/l. There was, however, a significant reduction to 0.26 g/d with Piconcentrations of < l mg/l. The effiency of microbial protein synthesis was variable but averaged approximately 25 g N/kg total carbothdrate fermented.5. It was estimated that the minimum Piconcentrations required in rumen fluid in vivo to maintain maximum degradative and synthetic microbial activities was in the range 75–100 mg/l and that the over-all P requirement of the microbes was of the order of 5.1 g/kg apparently digested organic matter intake.
Decrease in amylase (EC3.4.21.4) synthesis in lactating rats
Authors: Mizoguchi Junji , Imamichi Tomonori 
Published: September 2005

1. The amylase (EC3.4.21.4) and trypsin (EC3.2.1.1) activities in the pancreas in rats during pregnancy, lactation and after the weaning period, and the secretory responses to a secretagogue (caerulein) in the exocrine pancreas of lactating rats were measured.2. Trypsin activity increased as lactation progressed and reached twice that of unmated rats in the second half of the lactation period. The amylase activity fell before parturition and failed to recover even after the start of lactation and was significantly decreased throughout the lactation period.3. The total amount of pancreatic juice produced in the lactating rats was significantly greater than that of unmated rats; the amylase output was significantly less than that of unmated rats.4. When the pups were removed, amylase activity in the pancreas returned to the value in unmated rats. Furthermore, the amylase activity in lactating rats receiving a daily injection of insulin significantly exceeded that of normal lactating rats.5 These results indicate that the decrease in amylase activity in lactating rats is due to the reduction of amylase synthesis and there is a possibility that insulin is required for normal or elevated rates of amylase synthesis in lactating rats.
Relative nutritional availability to rats of selenium in Finnish spring wheat (Triticum aestivum L.) fertilized or sprayed with sodium selenate and in an American winter bread wheat naturally high in Se
Authors: Mutanen Marja , Koivistoinen Pekka , Morris Virginia C. , Levander Orville A. 
Published: September 2005

1. A Finnish national programme to fertilize crops with sodium selenate led us to compare the nutritional availability to rats of selenium in two Finnish spring wheats (Triticum aestivum L.), either fertilized or sprayed with sodium selenate, with that in an American winter bread wheat naturally high in Se.2. Weanling male rats were given a Se-deficient Torula yeast diet for 4 weeks followed by either continued depletion or repletion for 4 weeks with graded levels of Se as sodium selenite (standard) or wheat (test food). Plasma and liver Se levels and plasma and liver glutathione peroxidase (EC 1.11.1.9; GSH-Px) activities were used as criteria of body Se status.3. The availability of Se under these conditions was calculated with the point-slope technique at two dietary levels of Se (Expt 1) and with the slope-ratio method (Expt 2).4. In the point-slope assay, the level of dietary Se fed had a considerable effect on the apparent availability values obtained which made interpretation of the results difficult. In the slope-ratio assay, no difference in the availability of Se from the various wheats was observed when plasma or liver Se levels were used as the response criteria.5. The Se in the fertilized wheat was somewhat more available than that in the sprayed wheat when plasma or liver GSH-Px activities were the response criteria. Overall, availability values (% ) derived by averaging all four response criteria were 86, 77 and 73 for the fertilized and sprayed Finnish wheats and the American wheat respectively (sodium selenite 100).6. These results show that wheat is a relatively available source of Se to rats regardless of whether its Se content is naturally high or is increased by fertilization or spraying.
Factors influencing the absorption of iron from soya-bean protein products
Authors: Derman D. P. , Ballot D. , Bothwell T. H. , Macfarlane B. J. , Baynes R. D. , Macphail A. P. , Gillooly M. , Bothwell J. E. , Bezwoda W. R. , Mayet F. 
Published: September 2005

1. The absorption of iron from soya-bean (Glycine hispida)-based and milk-based infant formulas was assessed in 138 multiparous Indian women, using the erythrocyte utilization of radioactive Fe method.2. Fe absorption was significantly greater from the basal milk formula (1.5 g protein) than it was from the basal soya-bean formula (2.3 g protein), with geometric mean values of 0.083 and 0.044 respectively.3. Ascorbic acid markedly increased Fe absorption from the milk-based formula in a dose-dependent fashion. The increase was fivefold when the ascorbic acid: Fe ratio on a weight-for-weight basis was 6: 1 and over tenfold when it was 20:1. In contrast, ascorbic acid had a less-marked effect on the absorption of Fe from the soya-bean-based formula, with only a two- to threefold increase at an ascorbic acid: Fe ratio of 20: 1.4. The geometric mean Fe absorption from the soya-bean formula (1.27 mg Fe, 2.3 g isolated soya-bean protein (ISP)) was somewhat less than that from the same amounts of ISP and ascorbic acid made up in milk (0.075 and 0.1 13 respectively). However, a direct comparison between the soya-bean formula in milk and in water showed no significant difference (0.043 and 0.060 respectively).5. Fe absorption from a drink containing 10 g ISP and 30 mg ascorbic acid was significantly better than that from a similar drink containing the soya-bean flour from which ISP is extracted (0.044 and 0.027 respectively).6. Heating ISP to 200° for 2 h before its use had no effect on Fe availability. When 2.3 g heated ISP (10 mg ascorbic acid) was compared with a similar formulation of untreated ISP, Fe absorption values were 0.135 and 0.099 respectively. Comparable values with 25 g ISP (no ascorbic acid) were 0.067 and 0.058.7. Citric acid in amounts of 1 4 g had a dose related but limited enhancing effect on Fe absorption from 10 g ISP, with a rise from 0.01 1 (no citric acid) to 0.068 (4 g citric acid).8. There was appreciable variability in the levels of Fe absorption in different studies, which suggested that unidentified manufacturing or preparative differences might be influencing the overall results.
Detraining of exercise-trained rats: effects on energetic efficiency and brown adipose tissue thermogenesis
Authors: Arnold Jeff , Richard Denis 
Published: September 2005

1. Complete energy balance measurements were made in exercise-trained (treadmill running) rats subjected to 27 d of exercise detraining.2. The 20% difference in body-weight that existed at the end of the training period between sedentary and trained rats was negated by detraining. Detrained rats had twice the body-weight gain of their untrained controls.3. An elevation (12%) in metabolizable energy (ME) intake (relative to body-weight) was observed in detrained rats while their gross energetic efficiency was augmented by 60%.4. Energy expenditure, excluding the estimated costs of fat and protein storage, was similar for detrained and untrained rats. Complementing the latter was the finding that thermogenesis in brown adipose tissue, a known energy buffering process, was also similar.5. Elevated ME intake (relative to body-weight) largely contributed to the increased energetic efficiency of detrained rats.
Differential oxidation of saturated and unsaturated fatty acids in vivo in the rat
Authors: Leyton J. , Drury P. J. , Crawford M. A. 
Published: September 2005

1. The oxidation rates of lauric, myristic, palmitic, stearic, oleic, α-linolenic, linoleic, γ-linolenic, dihomo- γ-linolenic and arachidonic acids were studied by use of a radioisotope tracer technique in weanling rats at rest in a metabolism chamber over 24 h.2. Of the saturated fatty acids, lauric acid (12:O) was the most efficient energy substrate: the longer the chain length of the saturated fatty acids, the slower the rate of oxidation.3. Oleic acid (18:1) was oxidized at a remarkably fast rate, similar to that of lauric acid.4. Of the ω6 essential fatty acids studied, linoleic acid (18:2ω6) was oxidized at a faster rate than any of its metabolites, with arachidonic acid (20:4ω6) being oxidized at the slowest rate.5. The rate of oxidation of γ-linolenic acid (18:3ω3) was almost as fast as that of lauric and oleic acids.