bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparison of the effects of dietary calcium and phosphorus deficiency on the in vitro and in vivo metabolism of 25-hydroxycholecalciferol in the chick
Authors: Sommerville Barbara A. , Swaminathan R. , Care A. D. 
Published: May 2005

1. Young chicks fed a diet deficient in calcium showed an eightfold increase in the in vitro renal production of 1,25-dihydroxycholecalciferol (1,25-DHCC) and those fed a diet deficient in phosphorus showed a threefold increase when compared to chicks on a normal diet.2. The in vivo accumulation of 1,25-DHCC in the gut mucosa was doubled in both low-Ca and low-P groups as was the rate of Ca absorption from the duodenum and the Ca-binding protein activity. The accumulation of 1,25-DHCC in bone increased threefold in the low-Ca group but showed no change in the low-P group.3. It was concluded that the increased rate of Ca absorption found in dietary P deficiency depends rather upon the capacity of the gut mucosa to accumulate larger amounts of 1,25-DHCC than upon an increased renal production of this metabolite. The mechanism by which this is achieved is unknown, but it unlikely to be a general increase in availability of 1,25-DHCC since no rise occurred in bone 1,25-DHCC levels.
Total body water in malnutrition: the possible role of energy intake
Authors: Patrick J. , Reeds P. J. , Jackson A. A. , Seakins Anne , Picou D. I. M. 
Published: May 2005

1. Total body water (TBW) was measured using tritiated water in sixty-five children. The measurements were distributed throughout rehabilitation in order to define the effect of changing energy intakes.2. Oedematous children had a high TBW which decreased to the normal range during loss of oedema providing they were not receiving more than maintenance amounts of energy during this period.3. Marasmic children who had not received greater than maintenance amounts of energy had a normal TBW.4. Treatment with a high-energy diet was associated with an initial increase in TBW.5. The possible mechanisms for this phenomenon are discussed.
The use of a Thiry-Vella loop of jejunum to study the intestinal absorption of calcium and inorganic phosphate in the conscious pig
Authors: Fox J. , Care A. D. , Swaminathan R. 
Published: May 2005

1. Pigs, each surgically prepared with a Thiry-Vella jejunal loop were used to study the absorption of calcium and inorganic phosphate from the intestine.2. The loops were perfused daily for 6–8 h with a nutrient solution and absorption from the perfusate was measured.3. The technique employed minimized atrophy of the jejunal mucosa and enabled the measurement of hourly or daily changes in absorption rate of components of the luminal fluid.4. No differences were observed when polyethylene glycol (PEG; molecular weight 4000), [14C]PEG or 51Cr-EDTA were used as markers of net water movement.5. Increasing the concentration of Ca in the perfusate resulted in the demonstration of a two-component relationship between net absorption rate of Ca and intraluminal Ca concentration. An initial rapid absorption rate from 0 to 4 mm was found, then a slower rate from approximately 5 mm upwards which did not saturate at the highest concentration tested (25 mm).6. Increasing the concentration of phosphate in the perfusion solution increased the net absorption of phosphate from that solution. Although a two-component system, similar to that for Ca, was not evident, net absorption of phosphate was not saturated at the highest concentration tested (50 mm).7. The absorption of Ca was unaffected by the presence of phosphate in the solution but Ca (2.5 mm) enhanced the absorption of phosphate.
Tissue enzyme levels as indices of protein status in sheep
Authors: Payne E. , Laws L. 
Published: May 2005

1. An investigation was made to determine the value of tissue enzymes as indices of protein nutrition.2. Sheep were given a reduced protein intake for 6 weeks, whereupon some were given a protein supplement for 1 week and then the sheep were refed their initial diet. In the first experiment sheep were taken from pasture and given a reduced protein intake for 6 weeks whereupon some were given a protein supplement for 1 week and then all the sheep were grazed on pasture. In the second experiment sheep were fed on lucerne (Medicago sativa) chaffad lib.in place of grazing before and after the period of reduced protein intake during which one group was also fed on molasses. Again, another group was given a protein supplement for 1 week after 6 weeks on the reduced protein intake.3. As a result of reduced protein intake there were significant (P< 0.01) changes in the liver in the content of DNA, protein: DNA, arginine synthetase (combined activity of argininosuccinate synthetase (EC6.3.4.5) and argininosuccinate lyase (EC4.3.2.1)), aspartic aminotransferase (EC2.6.1.1), glutamic dehydrogenase (EC1.4.1.2), arginase (EC6.5.3.1) and tyrosine aminotransferase (EC2.6.1.5).4. There were few consistent changes in muscle in the levels of DNA, protein:DNA, creatine kinase (EC2.7.3.2) and aspartic aminotransferase.5. The feeding of molasses to one group tended to reduce the change in DNA level but still resulted in significant changes in the enzymes.6. It is suggested that the levels of arginine synthetase, aspartic aminotransferase and DNA in liver could be useful indices of protein status.
Amino acid requirements of the breeding sow: the dietary lysine requirement during pregnancy
Authors: Sohail M. A. , Cole D. J. A. , Lewis D. 
Published: May 2005

1. Four pregnant sows were used to study lysine requirements by means of the interpretation of values for plasma amino acid and blood urea. Diets containing graded levels of dietary lysine were fed at the rate of 1.82 kg/d.2. Plasma lysine remained at a low level up to 6.4 g dietary lysine/kg (dry matter basis) and then increased sharply with further increases in lysine intake.3. Blood urea levels decreased when the dietary lysine content was increased to 6.4 g/kg and then increased at higher dietary lysine concentrations.4. Both criteria of response indicated that the lysine requirement of the pregnant sow given 1.82 kg diet/d during the later stages of pregnancy does not exceed 10.00 g/d.
Effects of liquid feeding of concentrate from a pail on growth and on the digestibility of the diet in young calves
Authors: Abe M. , Shibui H. , Iriki T. , Kondoh K. , Kawai T. 
Published: May 2005

1. Studies were done on the effects of giving calves two types of concentrate diet, both in a liquid form from an open pail or in a dry pelleted form, on the closure of oesophageal groove, body-weight gains and the digestibility of rations.2. Twenty-four Holstein calves were used in an experiment by dividing into two groups of twelve calves each. The ‘dry-fed’ group (DFG) was given a pelleted concentrate, F1, from 25 to 42 d of age, and then given another type of pelleted concentrate, F2, from 43 to 87 d of age, and again given F1 from 88 to 112 d of age. The ‘liquid-fed’ group (LFG) was given from a pail a liquid suspension of the equivalent amount of the same concentrates as those fed to DFG calves, for the same periods. F1 contained skim milk and glucose with lower levels of maize and soya-bean meal than F2 which did not contain skim milk or glucose; F1 and F2 were both supplemented with 10 g methionine/kg and also supplemented with lysine at 5 and 10 g/kg respectively. All calves were allowed free access to roughage, and digestibilities were measured at 12 and 16 weeks of age.3. Wet weights of reticulo-rumen and abomasal tissues (% whole stomach weight) were respectively 69.8 and 17.6 in DFG, and 59.0 and 26.4 in LFG at 42 d of age; at 87 d of age, the corresponding values were 68.0 and 16.3 in DFG, and 52.8 and 36.6 in LFG, and further, LFG had significantly more developed caecums and large intestines as well as significantly less developed reticulo-rumens and omasums than DFG.4. Free amino acid patterns in plasma did not vary in DFG, but varied in LFG in response to the change in diet from F1 to F2 and to the difference between diets in lysine supplementation.5. Feeding F1 in a liquid form and F2 in a dry form significantly improved calf gains. The intake of roughage in DFG exceeded that in LFG especially when F2 was fed.6. The digestibility of diethyl ether extracts did not vary with feeding procedures, but that of crude protein (nitrogen × 6.25) was significantly higher in DFG independent of the type of diet. Digestibilities of dry matter and N-free extracts were significantly higher in LFG for F1, while higher in DFG for F2. The digestibility of acid-detergent fibre did not differ significantly between groups at 12 weeks of age, but was significantly higher in LFG at 16 weeks of age, suggesting a possible compensatory contribution of the large intestine to the digestion of fibre in LFG.7. The efficiency of liquid feeding of a concentrate diet to ruminants compared with that of dry feeding is discussed.
Sex, body composition and regulation of food intake during growth in the Zucker rat
Authors: Radcliffe J. D. , Webster A. J. F. 
Published: May 2005

1. Food intake and rates of protein, lipid and energy deposition during growth were measured for lean and congenitally obese (fatty) Zucker rats offered from 34 d of age to slaughter at 66 d of age, one of six semi-synthetic diets containing casein (C) in the following amounts (g C/kg): 40C, 100C, 150C, 300C, 500C and 700C.2. In Expt 1, groups of four male rats were offered each diet to appetite. The digestibility of dietary protein and metabolizability of dietary energy were determined. Total carcasses were analysed for protein, energy and lipid at 34 and 66 d of age. The results showed that, given diets containing 300C or above, both fatty and lean males regulate food intake so as to sustain a maximal rate of protein deposition. This maximal rate was greater in males than in females, and the sex difference was more marked in lean rats. Diets containing less than 300C did not permit maximal protein deposition and, in this instance, both sexes and phenotypes showed a similar reduction in food intake and protein deposition. The rate of deposition of body lipid did not appear to be controlled in either phenotype.3. In Expt 2, fatty and lean rats were pair-fed diets 100C and 500C. Carcass composition at 66 d of age confirmed that obesity in the fatty rat was not due to hyperphagia but to an abnormal pattern of energy utilization between fat deposition (too much), and protein deposition and heat production (too little).4. In Expt 3, fatty and lean, male and female rats were given diets 100C and 500C to slaughter at 66 d of age. The carcasses were analysed into different parts by weight, and according to protein and lipid contents of viscera, pelt and subcutaneous fat, and empty carcass. Fatty rats stored approximately 0.53 of their protein in the empty carcass, lean rats approximately 0.65.5. The results confirm that food intake in the Zucker rat is intimately related to the capacity of the animals for protein deposition, but this capacity differs between sexes and between phenotypes, and the distribution of body protein in the fatty rat eatingad lib.is not that of a normal rat.
Studies in iron supplementation of preschool children
Authors: Pereira Sheila M. , Begum Almas , Baker S. J. 
Published: May 2005

1. The effect of daily supplements of 20–30 mg inorganic iron as ferrous sulphate on the growth, activity and haematological status of preschool children was studied for 3.5, 7 and 12 months and compared to that of children who served as controls. All children were given their daily requirements of energy and protein. In addition, they received 5 μg cyanocobalamin and 200 μg folic acid.2. Fe supplementation increased the haemoglobin, serum Fe and percentage saturation of transferrin and reduced the unsaturated Fe-binding capacity significantly compared to corresponding values for the controls.3. Height and activity were unaffected by Fe supplements.4. Of the children 45% had haemoglobin values below 110 g/l at the end of 7–12 months of Fe supplementation.
Effects of vitamin B12deficiency on lipid metabolism of the rat liver and nervous system
Authors: Fehling C. , JÄgerstad Margaretha , Åkesson B. , Axelsson J. , Brun A. 
Published: May 2005

1. Rats bred from vitamin B12-depleted dams were fed on a vitamin B12-deficient diet for 12–15 months and developed a severe vitamin B12deficiency, as judged from methylmalonic acid excretion and tissue vitamin B12levels at slaughter. Control rats were supplemented with vitamin B12in the drinking-water.2. Neurological signs were recorded after 7 months but the motor nerve conduction velocities remained normal. Neuropathological examination revealed mild changes in the peripheral nerves but no changes in the central nervous system.3. The amounts of total lipids and phospholipids were normal, but in all examined tissues the proportions of pentadecanoate (C15fatty acid) and heptadecanoate (C17fatty acid) were considerably increased in vitamin B12deficiency.4.3H2O was incorporated to the same extent into the fatty acids of nervous tissue from vitamin B12-deficient and control rats after 48 h. Less3H was found in the liver fatty acids of the vitamin B12-deficient rats.5. Neurological dysfunction can be demonstrated in the vitamin B12-deficient rat; the relation of the biochemical and neuropathological changes to the neurological signs needs further study.
Studies on digestion and absorption in the intestines of growing pigs
Authors: Low A. G. , Partridge I. G. , Sambrook I. E. 
Published: May 2005

1. Digesta were collected from twenty-three pigs, initially of 30 kg live weight, and fitted with single Ash re-entrant cannulas in either the duodenum, jejunum or ileum. A further twenty-four pigs were used in a conventional digestibility trial.2. The diets contained: barley, fine wheat offal, white fish meal, minerals and vitamins (diet BWF); starch, sucrose, maize oil, cellulose, minerals, vitamins and either groundnut (diet SSG) or casein (diet SSC).3. The flow-rates of dry matter (dm), ash and water were measured hourly in the duodenum and jejunum, and every 6 h in the ileum during 24 h collection periods. Faeces were collected during 5 d periods.4. Marked increases in the flow rates of each of the digesta components after feeding each diet were observed in the duodenum and jejunum, but not in the ileum. The total flow in 24 h periods was much lower in the ileum than at the other sites.5. Values for the ratio, dm output:intake for dm outputs from the duodenal, jejunal or ileal cannulas, and in faeces, in 24 h periods were respectively 0.94, 0.81, 0.28 and 0.22 for diet BWF; 0.96, 0.76, 0.20 and 0.15 for diet SSG; 0.96, 0.73, 0.08 and 0.04 for diet SSC. The corresponding values for ash were: 1.47, 1.65, 0.74 and 0.53 for diet BWF; 1.28, 1.34, 0.59 and 0.51 for diet SSG; 1.63, 1.35, 0.50 and 0.26 for diet SSC. The corresponding values for water were: 3.49, 3.41, 0.88 and 0.18 for diet BWF, 2.75, 2.80, 0.80 and 0.08 for diet SSG and 2.61, 1.87, 0.23 and 0.01 for diet SSC.
Studies on digestion and absorption in the intestines of growing pigs
Authors: Partridge I. G. 
Published: May 2005

1. Pigs growing from 20 to 60 kg live weight were given diets based on barley, weatings and fish meal, or starch, sucrose and groundnut meal or starch, sucrose and casein. Seventeen pigs were fitted with single re-entrant cannulas in the duodenum (posterior to entry of bile and pancreatic ducts), jejunum or terminal ileum and twenty-four non-cannulated pigs were used in a conventional digestibility trial.2. The amounts of calcium, phosphorus, magnesium, sodium and potassium passing through the reentrant cannulas and amounts excreted in the faeces were measured. These values were used to calculate the direction and extent of net movements of the five elements through the walls of the four parts of the digestive tract anterior to the collection sites.3. The small intestine was the principal site of Ca and P absorption but there were differences between the diets in the relative importance of the regions anterior and posterior to the mid-jejunum.4. Secretion of small amounts of Mg occurred in the anterior small intestine; the ileum and large intestine were the principal sites of net absorption.5. There was a large net secretion of Na anterior to the duodenal cannulas and further secretion into the anterior small intestine with each diet. There were marked differences between diets in the amounts secreted but the ileal Na concentration was the same in each instance. Absorption occurred in the ileum and large intestine.6. Secretion of small amounts of K was evident anterior to the duodenal cannulas and net absorption occurred in both parts of the small intestine with each diet.
Studies on digestion and absorption in the intestines of growing pigs
Authors: Partridge I. G. 
Published: May 2005

1. Seven pigs of 30 kg initial live weight were fitted with re-entrant cannulas in the terminal ileum. Each was fed, in succession, four purified diets having cellulose and sodium levels (g/kg) of 30 and 2.7, 30 and 0.9, 90 and 2.7 or 90 and 0.9, respectively. Collections of digesta (24 h) and 3 or 4 d collections of faeces were made.2. There was a greater throughput of ileal digesta with the high-cellulose diets than with the low-cellulose diets, mainly due to increased water content, and there was a concomitant reduction in the net absorption of Na from the small intestine. The immediate response to reduced Na intake was increased secretion of Na into the gut lumen anterior to the terminal ileum; this was more pronounced with the high-cellulose diet. Na concentrations in ileal digesta were very similar for all four diets.3. The apparent absorptions of calcium, phosphorus, magnesium, potassium and zinc were reduced by the high-cellulose diets. In each instance this was due to reduced absorption posterior to the terminal ileum.
Blood pyruvate carboxylase (EC6.4.1.1) activity as a criterion of biotin status in chickens and turkeys
Authors: Whitehead C. C. , Bannister D. W. 
Published: May 2005

1. Blood pyruvate carboxylase (pyruvate-CO2ligase (ADP-forming);EC6.4.1.1; PC) activities in young chickens and turkeys given low-biotin diets supplemented with biotin at graded levels were studied in three experiments.2. In both species PC activity was related positively to the supplemental biotin level. The relationship was sigmoid and maximum activity was attained with supplemental levels above those required to give maximal growth response.3. Enzyme activity decreased between 2 and 4 weeks of age but remained almost constant thereafter.4. Activity in chicks was not affected by alterations in the fat or protein content of the diet.5. Changing poults from high to low and from low to high supplemental biotin levels resulted in reversals in the levels of enzyme activity.6. It is concluded that blood PC activity is a promising new criterion for assessing the biotin status of young chickens and turkeys.
Metabolic changes associated with intake by cows of complete diets containing straw and concentrates in different proportions
Authors: Bines J. A. , Davey A. W. F. 
Published: May 2005

1. Pelleted diets containing concentrates and 0, 200, 400 or 600 g chopped straw/kg were fed ad lib. for 5 h daily to four cows. Concentrations of various energy-yielding metabolites were measured in samples of rumen fluid and jugular blood taken before feeding and at intervals after food was offered.2. After feeding, the pH of rumen fluid decreased rapidly and the total concentration of volatile fatty acids (VFA) increased; the changes were greatest in the diet containing no roughage. The changes were essentially complete by 135 min at approximately the time feeding stopped. Rumen lactate concentrations were always low and increased significantly only in cows given no roughage.3. There were highly significant relationships between the peak rumen acetate concentration after a meal and the apparent digestibility of the dry matter of that meal, and the amount of material in the rumen at the end of a meal. The latter relationship resulted in there being no difference between treatments in the total amount of acetate present in the rumen after feeding.4. In the blood, concentrations of acetate, propionate, β-hydroxybutyrate (BHB) and lactate all increased after feeding. The increase was prolonged and maximum values were rarely reached before 4–5 h. The highest concentrations of acetate and BHB were found in cows given 200 g roughage/kg and were twice as great as those in cows given no roughage; lower concentrations were found in cows given 400 or 600 g roughage/kg. This information, together with the rumen concentrations of acetate and butyrate, was interpreted as indicating an inhibition of VFA absorption from the rumen of cows given no roughage.5. Plasma glucose concentrations decreased rapidly for 4 h after feeding, the decrease being greatest in cows given 200 g roughage/kg. Non-esterified fatty acid concentrations also decreased after feeding 200 and 0 g roughage/kg rations, but concentrations were not high at any time.6. It is concluded that chemical changes in the rumen correspond to feeding behaviour much more closely than changes in blood and therefore any chemostatic regulation of food intake probably occurs at the former site, with acetate playing a major role. Monitoring energy balance at tissue level is likely to be mediated hormonally, with insulin an important factor.
On supplementing the selenium intake of New Zealanders
Authors: Thomson Christine D. , Burton Catherine E. , Robinson Marion F. 
Published: May 2005

1. Urinary and faecal excretion of single oral doses of 1 mg selenium or 0.1 mg Se as selenomethionine (Semet-Se) in solution were studied in two women. Most of the Se was absorbed and little was eliminated in the urine (0.05–0.22 dose).2. The results have been compared with those from an earlier study (Thomson, 1974) on the same two women after similarly sized doses of sodium selenite (selenite-Se) in solution. Although selenite-Se was almost as well absorbed as Semet-Se more was excreted in the urine (0.41–0.85 dose).3. Repeated dosing with 1 mg selenite-Se on five consecutive days in one of the women indicated that 1.1 mg had been retained.4. Twenty patients with muscular complaints from Tapanui (South Otago, New Zealand), a low-Se soil area, ingested 0.5 mg selenite-Se daily for 20 d. Blood Se increased rapidly to almost twice the initial concentration but reached a plateau well below most values reported for residents outside New Zealand. No difference in blood Se concentration was found between those who did or did not report improvement.5. Spasmodic medication with selenite-Se by some residents near Lincoln (Christchurch, New Zealand) for periods of up to 10 years or more had increased the blood Se somewhat.