bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary intake of fluoride ashed (total fluoride) v. unashed (inorganic fluoride) analysis of individual foods
Authors: Taves Donald R. 
Published: September 2005

1. Fluoride content in ninety-three individual food items from a hospital in a fluoridated area was determined by ashing (total fluoride) v. unashing (inorganic fluoride) analysis.2. No discrepancy between the two methods was found by food group but two dry cereals and black pepper did show significantly more fluoride after ashing. The reason for the unavailability before ashing was not determined.3. Daily fluoride intake was estimated at 1·783 mg which is midway between the 1·211 and 2·201 mg reported from studies in which composite diets were analysed.4. Daily intake from food at 0·4 mg was one-quarter of the daily total intake of 1·8 mg; a ratio consistent with those previously reported in serum, urine and bone between residents from a non-fluoridated v. fluoridated community.
Storage of milk powders under adverse conditions
Authors: Hurrell R. F. , Finot P. A. , Ford J. E. 
Published: September 2005

1. Whole-milk powders containing 25 g water/kg were stored for up to 9 weeks in sealed aluminium containers at elevated temperatures. Lysine and other essential amino acids were measured by chemical and microbiological methods.2. Storage at 60° resulted in the progressive formation of lactulosyl-lysine. After 9 weeks, 30% of the lysine groups were present in this form. The powders still retained their natural colour and the levels of tryptophan, methionine, cyst(e)ine and leucine remained unchanged.3. Storage at 70° resulted in the formation of lactulosyl-lysine followed by its complete degradation with the development of browning. Available tryptophan, methione, leucine and isoleucine decreased progressively during storage.4. The different methods for lysine determination gave widely dissimilar results. The direct fluorodinitrobenzene (FDNB) technique and reactive lysine from furosine were considered to be the most reliable methods. The FDNB-difference, dye-binding lysine,Tetrahymena and Pediococcusmethods all seriously underestimated reactive or available lysine in heat-damaged milk powders.TetrahymenaandPediococcusappeared to utilize lactulosyl-lysine as a source of lysine.5. The results are discussed in relation to storage and distribution of milk powders in hot climates.
Studies on gastric digestion of protein and carbohydrate, gastric secretion and exocrine pancreatic secretion in the growing pig
Authors: Zebrowska Teresa , Low A. G. , Zebrowska Hanna 
Published: September 2005

1. Six pigs, initially of 35 kg mean live weight, were each fitted with a re-entrant cannula. This was formed on either side of a short pouch of duodenum into which the pancreatic duct opened and which contained a simple cannula linked to the centre of the re-entrant cannula.2. Each pig received two diets: diet A was based on wheat starch, sucrose and casein, while diet B was based on barley and soya-bean meal. The diets were given in equal amounts at 12 h intervals.3. Digesta and pancreatic juice were collected continuously during three 12 h periods for each pig on each diet.4. Mean duodenal output: dietary intake values for diets A and B respectively were: digesta 1·80, 2·86; dry matter 1·05, 1·03; nitrogen 1·05, 1·06; trichloroacetic acid (TCA)-soluble N 7·69, 9·10; glucose 0·97, 0·89. For diet A the proportion of TCA-soluble N in total N rose from 13 to 50% during 12 h, while it was approximately 50% throughout 12 h for diet B.5. Mean total pepsin (EC3.4.23.1) activities (units/24 h) were 760449 (diet A) and 1466571 (diet B).6. Salivary and gastric secretions were calculated to be approximately 4 and 8 kg/24 h for diets A and B respectively.7. Mean flows in pancreatic juice (g/24 h) for diets A and B respectively were: juice 1204, 2182; protein 10·94, 12·10; N 1·98, 2·14; ash 9·46, 17·31; sodium 3·88, 6·91; potassium 0·23, 0·54: calcium 0·031, 0·046; phosphorus 0·024, 0·026.8. Mean total enzyme activities (units × 10−3/24 h) for diets A and B respectively were: trypsin (EC3.4.21.4) 138, 114; chymotrypsin (EC3.4.21.1) 84, 84; carboxypeptidase A (EC3.4.2.1) 5, 4; carboxypeptidase B (EC3.4.2.2) 15, 17; amylase (EC3.2.1.1) 1061, 981.9. It was calculated that the minimum amount of endogenous N from saliva and gastric secretion was 0·3–0·6 g in 24 h. This assumes no absorption of N occurred anterior to the duodenal cannula.
The effect of zinc deficiency on glucose metabolism in meal-fed rats
Authors: Reeves Philip G. , O'Dell Boyd L. 
Published: September 2005

1. The incorporation of uniformly-labelled [14C]glucose into fatty acids and glycogen of adipose tissue and liver was used to assess the effects of zinc deficiency on glucose metabolism in meal-fed rats.2. Throughout the study, identical feeding regimens were maintained between each of the Zn-deficient groups and their appropriate controls. The feeding regimens were either meal-feeding orad lib. feeding.3. Zn deficiency reduced [14C]glucose incorporation into fatty acids of epididymal fat pads of meal-fed rats by 75% when compared with meal-fed controls.4. Zn deficiency caused a slight but significant decrease in [14C]glucose incorporation into liver fatty acids of meal-fed fats when compared with meal-fed controls.5. Zn deficiency significantly increased [14C]glucose incorporation into liver glycogen of meal-fed rats in Expt. 2 but not in Expt 1.6. Some effects of Zn deficiency on glucose metabolism were shown to be independent of the feeding regimen when a single daily meal was given to both Zn deficient and control groups. This method of feeding may be a useful approach to study the effects of Zn on glucose metabolism in the rat.
Kinetics of [103Ru]phenanthroline and dysprosium particulate markers in the rumen of steers
Authors: Dixon R. M. , Kennelly J. J. , Milligan L. P. 
Published: September 2005

1. Two rumen cannulated steers consuming 5·5 kg air-dry lucerne (Medicago sativa) hay/d given at two-hourly intervals were used to study the kinetics in the rumen of the two particulate markers, 103Ru-labelled Tris-(1,10-phenanthroline) ruthenium II chloride ([103Ru]P) and dysprosium (Dy). Provision of markers was achieved by allowing the steers to eat separatedstems of the hay on to which had been sprayed solutions of the markers.2. The intake of large-particle (retained by a 3·2 mm mesh screen) dry matter (DM) in boluses and the rumen large-particle pool size measured by emptying the rumen wereused to calculate the turnover rate-constant of this pool (1·02 and 1·19/d for steers A and B respectively).3. The decline with time of both [103Ru]P and Dy associated with large-particle DM in raft digesta was best described by two-compartmental kinetics. The first compartment apparently reflected a combination of the processes of mixing of labelled particles throughout the rumen contents, physical migration of marker from the labelled hay, and physical breakdown of large particles to small particles.4. The disappearance with time of [103Ru]P and Dy associated with small particles from the raft, ventral digesta and faeces from 3 to 8 d was well described by a single kinetic compartment with a rate constant similar to that of the second compartment of the large particles from the raft.5. [103Ru]P was rapidly distributed through both the raft and ventral digesta of the rumen. This observation, taken together with measurements of migration of [103Ru]P, suggested that on entering the rumen much of the [103Ru]P did not remain associated with the original feed material.6. The majority (63–64%) of Dy entered the raft digesta and mixed only slowly through the rumen contents. Some Dy (18–27%) apparently migrated rapidly from large particles and to small particles immediately after ingestion and there was also evidence for some slow migration from small to large particles.7. When used under the conditions described for this experiment neither [103Ru]P nor Dy was satisfactory as a marker to trace the passage through the rumen of a particular meal.
Growth and development of rats artificially reared on a high or a low plane of nutrition
Authors: Smart J. L. , Stephens D. N. , Katz H. B. 
Published: September 2005

1. In order to exclude the possibility of differences in maternal care which are known to result from typical methods of undernutrition during the suckling period, rat pups were reared artificially on different planes of nutrition away from their mothers.2. Artificial rearing was accomplished by fitting infant rats with a gastric cannula through which a milk substitute was infused intermittently. Rats were fed thus from 4 to 21 d on a high (ARHI) or a low (ARLO; 44% of ARHI level) plane of nutrition. Underfeeding of the ARLO group was continued till 25 d, after which all rats were given a good-quality pelleted diet ad lib.3. Compared with mother-reared (MR) litter-mates, ARHI rats showed advanced eye-opening and, at 21 and 25 d, they resisted restraint more strongly.4. Growth in body-weight of ARHI and MR rats was similar but, when autopsied at 32 weeks, the ARHI rats were shorter (nose–rump length) and had lighter gastrocnemius muscles, adrenals and brains, but heavier epididymal-fat pads.5. ARLO rats had deficits at 32 weeks compared with ARHI rats in whole body, kidney and epididymal-fat-pad weights, and in tibia length.6. In a second experiment, ARHI and MR rats were killed at 21 d. All the differences found at 32 weeks were already present at 21 d. In addition, the ARHI pups had enlarged livers and intestines but shorter tibias.7. The milk substitute, which is one commonly used in such studies, has a low protein and high carbohydrate content compared with rats' milk. This difference probably caused the abnormal organ growth of ARHI rats.
Dependence of 24 h energy expenditure in man on the composition of the nutrient intake
Authors: Dauncey M. J. , Bingham S. A. 
Published: September 2005

1. The influence of the nutrient composition of food on energy expenditure during a 24 h period was investigated in adult volunteers. The maximum probable effect was determined using iso-energetic diets high in either protein or in glucose.2. Two men and four women took part in the study. Their body-weights and body composition were within the normal range. Each subject lived for 28 h in a whole-body calorimeterset at 26°, on two separate occasions. During each session they ate one of the following iso-energetic diets: high-protein–low-carbohydrate or high-glucose–low-protein.Energy expenditure was determined while the subject followed a pre-set pattern of activity. A 24 h collection of urine was made and total nitrogen, creatinine and urea excretions were determined, so that heat production could be corrected for protein metabolism.3. Two independent measures of energy expenditure were made: direct calorimetry was used to obtain heat loss partitioned into its sensible and evaporative components, while indirect calorimetry was used to estimate heat production from oxygen consumption, carbon dioxide production and N excretion. There was good agreement between the two estimates of 24 h energy expenditure: for the twelve sessions in the calorimeter the mean difference between heat production and heat loss was only 0·4 (SEM 0·39)%.4. The results showed that nutrient composition can have a marked influence on 24 h energy expenditure in adult humans. Mean values of 8659 (SEM 230) kJ and 7735 (SEM 250) kJ were obtained for the high-protein and high-glucose diets respectively. This 12% increasein energy expenditure on the high-protein intake was significant (P< 0·001). On the high-glucose intake, total heat loss comprised 22 and 78% evaporative and sensible heat losses respectively. The increase in heat loss onthe high-protein intake was accounted for by a 39% increase in evaporative heat loss and a 7% increase in sensible heat loss.5. It is concluded that the composition of the nutrient intake has a greater influenceon the metabolic rate of adult humans than has been suggested by some groups of workers in recent years.
Studies on the availability of iron in potatoes
Authors: Fairweather-Tait Susan J. 
Published: September 2005

1. Iron availability in potatoes and ferrous sulphate was measured in rats in a 10 d balance study and from a single meal using59Fe and55Fe as extrinsic labels.2. Dried potato samples were incubated in gastric juice in vitro and the amount solubilized was compared with other foods. The relationship between ascorbic acid content of dried potato and Fe solubilization was examined in vitro.3. In the balance study, the rats absorbed (mean with SE) 15·2 (2·7)% Fe from the diet containing 660 g dried potato/kg and 32·1 (2·8)% Fe from the semi-synthetic diet containing FeSO4. Absorption was higher from the extrinsically-labelled single meal: 49·6 (1·1)% Fe from59Fe-labelled potato and 62·4 (1·2)% Fe from59FeSO4.4. The in vitro experiments showed a much greater solubilization of Fe from potato than from the other foods examined. There was a correlation between Fe solubilization and ascorbic acid content of potatoes (rs0·76,P< 0·00).5. It appears that potatoes contain Fe of moderate availability, possibly higher than most vegetables. They also provide ascorbic acid which may enhance Fe absorption from a meal if present in sufficient quantities. Thus potatoes may make a useful contribution towards the Fe nutriture of the UK population.
Simultaneous determination of absorption of selenium from poultry meat and selenite in young men: application of a triple stable-isotope method
Authors: Christensen Merrill J. , Janghorbani Morteza , Steinke Fred H. , Istfan Nawfal , Young Vernon R. 
Published: September 2005

1. A triple stable-isotope method was used to estimat simultaneously selenium absorption from poultry meat intrinsically labelled with74Se and from an extrinsic tracer of76SeO32−in four young adult men. The subjects received an experimental diet based on chicken meat as the source of protein. Two diet periods, lasting from 5 to 10 d, depending on the frequency of stool output for each subject, were conducted to allow duplicate determinations within each subject of Se absorption from both sources.2. Absorption of Se was determined by the faecal isotope balance procedure through monitoring the stable isotopes74Se,76Se and80Se by means of radiochemical neutron activation analysis.3. For the separate periods, mean (with SEM) absorption of74Se from the intrinsically-labelled poultry meat was 70·9 (1·5)% and 72·0 (2·5)%. The absorption of Se from76SeO32−was 34·7 (5·5)% and 37·6 (3·2)% during the same periods.4. From these results it is concluded that, under the present experimental conditions, the intrinsic and extrinsic Se isotopes did not form a common pool before absorption. Possible reasons for this are discussed.
The effect of body condition on metabolic changes associated with intake of food by the cow
Authors: Bines J. A. , Morant S. V. 
Published: September 2005

1. Changes in concentrations of metabolites in blood and rumen fluid were measured in cows when fat and when thin and when given hay and concentrates at a restricted level or ad lib.2. When fed ad lib., cows consumed 24% more food when thin than when fat.3. Concentrations in rumen fluid of acetate and propionate after feeding at both levels did not differ significantly between fat and thin cows.4. Concentrations in blood of the lipogenic substrates acetate and 3-hydroxybutyrate did not differ between fat and thin cows after feeding, but glucose concentration fell more rapidly in thin cows especially when fed ad lib. Propionate rose more in thin cows than in fat cows when fed ad lib. Non-esterified fatty acids were higher in fat cows before feeding, but fell to similar levels to those in thin cows after feeding.5. The results are interpreted as indicating a more rapid rate of fatty acid synthesis in adipose tissue of thin cows. This in turn tends to lower blood levels of fatty acid precursors and so enhance the rate of their absorption from the rumen. This in turn permits higher intake of food before short-term chemical regulators of intake start to operate.
Effects of addition of kaolin or cellulose to an elemental diet on intestinal cell proliferation in the mouse
Authors: Goodlad R. A. , Wright N. A. 
Published: September 2005

1. Various methods of estimating intestinal mass and cell proliferation were used to compare the effects of a pelleted laboratory diet (diet A), an elemental diet (Flexical; diet B), Flexical plus kaolin (diet C) and Flexical plus cellulose (diet D) on the mucosa and other tissues of the mouse small intestine and colon.2. The weight of the distal third of the small intestine was significantly decreased in mice given diets B, C and D (P< 0·001). The length of the colon was significantly decreased in the mice given diets B (P< 0·001), C (P< 0·01) and D (P< 0·05); however, the weight of the colon was only decreased in the mice given diet B or diet C (P< 0·001).Similar changes were noted in the weights of the intestinal muscle and serosa layers; however, no such changes were noted in the weight or DNA content of the mucosa.3. No changes were observed in the crypt cell production rate in the small intestine, apart from an increase in the mid-region (P< 0·01) of mice given diet C, which was associated with a similar increase in the mucosal content of DNA.Crypt-cell production was significantly decreased (P< 0·01, 0·001) in the two sites of the colon studied in the mice given diets B or C, but the crypt-cell production rates were not significantly different from control levels at either site in the mice given diet D.4. The length of the colonic crypts was significantly decreased (P< 0·05, 0·02) in mice given diets B and C, but not in those given diet D; total cell number showed a similar change (P< 0·01, 0·05).The correlation coefficient between the length of the colonic crypts and absolute cell number was 0·513.5. The conclusion of the present study was that dietary fibre (cellulose), but not inert bulk (kaolin), prevents mucosal atrophy of the colon of mice given a fibre-free diet, and that many of the observed changes in intestinal weight are due to reduction in the bulk of the muscle layer.
Investigation of nitrogen balance in dairy cows and steers nourished by intragastric infusion
Authors: Ørskov E. R. , MacLeod N. A. , Fahmy S. T. M. , Istasse L. , Hovell F. D. DeB. 
Published: September 2005

1. Two dairy cows were maintained by intragastric infusion of volatile fatty acids and casein. Except when fasting, the casein-nitrogen was held constant, while total gross energy supply was varied from zero during fasting to 650 kJ/kg body-weight (W)0·75.2. One cow was estimated to attain zero N balance at an energy intake of 255 kJ/kg W0·75and the other at 307 kJ/kg W0·75, which was calculated to be substantially below the estimated energy required for zero energy balance.3. When the cows were later given an N-free infusion for a period preceding the trial, N balance occurred at 98 kJ/kg W0·75for one cow and 115 kJ/kg W0·75for the other.4. Four steers were similarly nourished by intragastric infusion and the energy nutrient increased from 0 at fasting to 450 kJ/kg W0·75. The protein was held constant at 1 g N/kg W0·75except at fasting. The energy level at which N balance occurred was 154 (SE 38) kJ/kg W0·75or approximately equal to the energy content of the protein. The practical implications of these findings are discussed.
The effect of high-protein and high-carbohydrate diets on [125I]iodoinsulin binding in skeletal muscle plasma membranes and isolated hepatocytes of rainbow trout (Salmo gairdneri)
Authors: Ablett Richard F. , Taylor Matthew J. , Selivonchick Daniel P. 
Published: September 2005

1. [125I]iodoinsulin-binding studies in the presence of a concentration range of bovine insulin were conducted to establish specific insulin-binding levels in skeletal muscle plasma membranes and isolated hepatocytes of rainbow trout (Salmo gairdneri) reared on control, high-protein or high-carbohydrate diets.2. Negative co-operativity was observed and receptor concentrations and apparent dissociation constants established for each preparation.3. No differences of specific binding attributed to diet were detected in skeletal muscle plasma membrane preparations; however, the receptor concentration of isolated hepatocytes from high-carbohydrate-reared trout was increased. This contrasted to comparable mammalian studies.
The intake of milk by suckled, newborn lambs and the effects of twinning and cold exposure
Authors: Thompson G. E. 
Published: September 2005

1. Clun Forest ewes with single and twin lambs were exposed to neutral (20°) or cold (−1°) environmental temperatures, beginning soon after parturition, for 4 d. The intakes of milk, lactose and glycerides by the lambs were calculated from measurements of the rate of displacement of tritiated water (injected into the lambs) by non-radioactive water in milk from the ewes, and measurements of the concentration of lactose and glyceride glycerol in small samples of milk.2. The yield of milk from ewes bearing twin lambs was greater than the yield from single-bearing ewes in the neutral environment but, in both environments, twin lambs had lower intakes of milk and milk lactose and glycerides, and gained body-weight more slowly, than single lambs. Milk from twin-bearing ewes had a lower lactose concentration than milk from single-bearing ewes.3. Cold exposure reduced the intake of milk and milk lactose, and reduced the rate of weight gain, of single and twin lambs. Glyceride intake was not different in the two environments.4. There appears to be a conflict between reduced supply of milk by the ewe and increased demand for milk by the lamb in cold temperatures. Such a conflict is sharpened when twin lambs are born.
Rate of endogenous methionine oxidation in rats at different levels of methionine intake
Authors: Neale R. J. , Waterlow J. C. 
Published: September 2005

1. The fractional rates of loss of 14C and body-weight were measured in growing female rats after a single dose of [1-14C]methionine. After the dose, the rats were maintained for 30 d on diets containing graded amounts of methionine and killed at 30 d.2. By 20 d after the dose the level of labelling of body proteins was fairly uniform. From 20 to 30 d, 14CO2 was collected at intervals. The rats were killed at 30 d and the total radioactivity remaining in the body was measured.3. The fractional loss of 14CO2 between days 20 and 30 was constant regardless of methionine intake except at the highest intake level.4. After correcting the fractional loss of 14CO2 for urinary 14C loss, a value of 35 mg/kg body-weight (20 mg/kg body-weight0·75) was obtained for the rate of endogenous methionine oxidation.
Losses in weight and body water in sows after weaning
Authors: Zoiopoulos P. E. , Topps J. H. , English P. R. 
Published: September 2005

1. The loss of body water of eight sows in the 7 d following weaning was determined using the deuterium oxide dilution technique. Four of the sows had received a concentrate diet in restricted amounts while the other four had been given the same diet mixed with two-thirds its weight of oat husksad lib. during the whole of the preceding lactation. Certain blood and urine constituents were also measured.2. Loss of body water was significantly less (P < 0·05) than weight loss of fasted animals, but body water losses were considerable in six of the eight animals.3. Excretion of urinary nitrogen, urea and creatinine and levels of plasma urea were higher, while levels of plasma non-esterified fatty acids and the hydroxyproline index were lower 1 week after weaning compared with values obtained on the day following weaning.4. These results indicate that in addition to water loss, depletion of body tissue, including protein, occurs in the newly-weaned sow.