bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differences in the metabolism of esterified and unesterified linoleic acid by rumen micro-organisms
Authors: Moore J. H. , Noble R. C. , Steele W. , Czerkawski J. W. 
Published: May 2005

1. Sheep were given intraruminal infusions of maize oil or linoleic acid and samples of contents were taken from the rumen and abomasum at different times after the infusions. Hydrolysis of the maize oil occurred in the rumen with the production of mono- and di-glycerides as intermediates. Linoleic acid derived from the maize oil was hydrogenated to stearic acid. When linoleic acid was infused into the rumen, little or no stearic acid was produced and octadecenoic acid accumulated.2. When linoleic acid or maize oil was incubated with rumen contents in an artificial rumen and samples of the reaction mixtures were taken from the apparatus after various time intervals, the results were similar to those obtained in vivo, except that the hydrolysis of maize oil did not give rise to mono- and di-glycerides.3. These results are discussed in relation to previous findings on the effects of intraruminal infusions of maize oil or linoleic acid on the fatty acid composition of the blood triglycerides of sheep.
Time relationships between the elevation of the serum amino acid ratio and changes in liver composition in malnourished rats
Authors: Grimble R. F , Sawyer M. B , Whitehead R. G 
Published: May 2005

1. Changes in the serum amino acid ratio have been compared with alterations in liver composition in young rats growing on three different diets, control, low-protein and ‘undernourished’. The rate of growth in the latter group was controlled to be the same as in the low-protein animals.2. The amino acid ratio only became elevated in the protein-deficient animals but not to the degree found in protein-malnourished children.3. Protein/g DNA was lost from the livers of the protein-deficient rats and this occurred at the same time as the serum amino acid ratio rose. The possibility that the two phenomena might be linked is discussed. Protein loss from the liver was not a feature in the undernourished animals.4. Reduced serum total protein and albumin concentrations also developed in the rats fed the low-protein diet and this occurred as the amino acid ratio started to rise.5. The liver did not become fatty in the low-protein animals until after the amino acid ratio had reached its maximal value. It was concluded, therefore, that the distorted pattern of serum amino acids could not be a result of this pathological condition.6. There was no apparent relationship between liver RNA levels and the magnitude of the serum amino acid ratio.7. The limitations of the rat as animal model for the study of chronic protein malnutrition in early childhood are discussed.
The urinary excretion of metabolites of riboflavine by man
Authors: West D. W. , Owen E. C. 
Published: May 2005

1. A dose of 1 g of riboflavine caused a large excretion of the vitamin in human urine and the rate of excretion showed more than one maximum.2. Various degradation products of riboflavine appeared in the urine approximately 24 h after the dose was administered and two of these were identified as 7,8-dimethyl-10-(2-hydroxy-ethyl)isoalloxazine, and 7,8-dimethyl-10-formyl-methylisoalloxazine. Reasons are given for believing that the degradation of riboflavine was due to bacterial action in the colon.
Calcium balance studies on children accustomed to low calcium intakes
Authors: Begum Almas , Pereira Sheila M. 
Published: May 2005

1. Calcium balance studies were carried out on twenty-eight apparently normal preschool children who had been for several months on a low Ca intake of 200 mg/child per day.2. Three-day balances showed that all subjects were in positive balance. The absorption was 50% of the intake.3. When the dietary intake was increased to 280 mg/day there was a greater absorption and retention of Ca. Serum Ca, inorganic phosphorus and alkaline phosphatase were within the normal range for this age group.4. Fourteen of the subjects were on wheat supplemented with lysine. The addition of a single amino acid to the diet was shown not to improve the absorption and retention of Ca over that of the controls.
Nutritive value of proteins of pearl millet of high-yielding varieties and hybrids
Authors: Goswami A. K , Sharma K. P , SEHGAL K. L 
Published: May 2005

1. Two high-yielding varieties and three hybrids of pearl millet were evaluated for their chemical composition and protein efficiency ratio (PER) for rats at a level of 6.38% dietary protein. PER values ranged from 0.94 to 1.21 and were significantly different.2. Tryptophan contents of the proteins were above the optimum level of the FAO reference protein. Lysine content was deficient in all the samples and was probably the limiting amino acid in the PER test.
The effect of protein-calorie malnutrition on the composition of the human femur
Authors: Dickerson J. W. T. , John P. M. V. 
Published: May 2005

1. A femur was analysed from each of the following malnourished children: five Turkish (4–7.5 months; marasmic), eight Jamaican (9–13 months; two marasmic, one marasmic with kwashiorkor, three with kwashiorkor, two ‘malnourished’) and two Ugandan (11 and 12 months; marasmic and with kwashiorkor respectively). These were matched with appropriate controls. Dry weight, fat, total nitrogen, collagen N, calcium and phosphorus were determined, and values are presented for them in the bone, with and without epiphyses, and in the epiphyses and cortex.2. The femurs of the Turkish children (4–7.5 months) showed greater deficits in length, Ca and P than did those of the Jamaican and Ugandan children (9–13 months). In both age-groups, regardless of the clinical condition, there was significantly less dry fat-free bone tissue than in control bones of similar ages. The concentration of fat in the bones was variable, but in the Turkish bones it was higher than in the controls.3. When the epiphyses were excluded, the femurs of the Jamaican and Ugandan children with kwashiorkor contained a lower concentration of total N per 100 g fat-free solids than did those of children with marasmus.4. The epiphyses of the malnourished children aged 4–7.5 months contained lower concentrations of total N, collagen N, Ca and P than those of controls. In the older age-group the only significant difference was a lower level of Ca.5. The cortex of all the malnourished children had a similar composition to that of the controls.
Fermentation of various soluble carbohydrates by rumen micro-organisms with particular reference to methane production
Authors: Czerkawski J. W. , Breckenridge Grace 
Published: May 2005

1. The fermentation of twenty-six different carbohydrates was studied in an artificial rumen.2. The rates of fermentation varied widely, but except in the case of rhamnose the amount of methane produced was usually related to the amount of carbohydrate fermented (6.0 Cal/ 100 cal of substrate). There was also a correlation between the amount of carbohydrate fermented and the amounts of steam-volatile acids formed.3. Glucose, fructose and sucrose were fermented rapidly but mannitol, sorbitol, glucuronic and galacturonic acids, glucosamine, D(–)-arabinose, ribose, sorbose, trehalose and starch were fermented very slowly or not at all. L(+)-Arabinose, xylose, galactose, mannose, cellobiose, maltose, lactose, raffinose, inulin, xylan and pectin were fermented at appreciable rates.4. The methyl-pentose, rhamnose, was fermented but no methane was produced. Fucose was fermented very slowly.5. The fermentation of sucrose and its constituent hexoses was characterized by a transient accumulation of lactate. The fermentation of rhamnose and of glucosamine was accompanied by permanent accumulation of lactate. No measurable amounts of lactate were produced when any of the other sugars were fermented.
Vitamin A and protein interrelationships in the milk-fed lamb
Authors: Faruque O. , Walker D. M. 
Published: May 2005

1. The mean liver retinol reserve (retinal + retinyl esters, expressed as retinol) of six newborn lambs was 21±8 μg. The mean value for ten suckled lambs, aged 5–7 days, was 2655±472 μg retinol per liver.2. Three unsuckled lambs were fedad lib. from birth for 28 days on a high-protein diet, based on lard and skim milk, without supplementary vitamin A. The diet provided sufficient vitamin A for normal growth, but insufficient to permit substantial liver reserves (43±8 μg retinol per liver).3. Thirty-six suckled lambs aged 5–7 days were given either a low-or a high-protein diet for 21 days, with or without graded levels of retinyl acetate or βcarotene. There were no significant differences in the live-weight gain or in liver retinol reserves between the low-and highprotein dietary treatments, or between the supplemented and unsupplemented groups.4. Twelve lambs were pair-fed on either a low-or a high-protein diet from birth for 21 days. Six lambs that were given a large supplement of retinyl palmitate on the 1st day of life had stored significantly less retinol in the liver at 21 days (P > 0.01) than six lambs given a somewhat smaller total amount of retinyl palmitate in small daily doses. Lambs given the high-protein diet had significantly greater liver retinol reserves (P > 0.01) than lambs given the low-protein diet, with both methods of supplementation.5. Twelve lambs were pair-fed from birth on a high-protein diet for 2 or 6 days. Lambs that were given retinyl palmitate dissolved in either a low-or a high-protein diet on the 1st day of life had significantly lower liver retinol reserves some 24 h later (P > 0.01) than lambs given similar treatments on the 5th day of life. Liver retinol reserves were positively correlated with the protein concentration of the diet at the time of supplementation.6. Eighteen lambs were pair-fed from birth with either a low- or a high-protein diet. Six pairs were given retinyl palmitate daily and three pairs were given the supplement 48 h before slaughter. The source of protein was casein. Eight out of nine lambs given the low-protein diet would have died had they not been slaughtered at between 8 and 11 days of age. The time of supplementation had no significant effect on liver retinol reserves, which were very low, regardless of the dietary protein concentration. Lambs given the high-protein diet retained a significantly greater proportion (P > 0.05) of the dietary retinyl palmitate than lambs given the low-protein diet.
The relative biological potencies of retinyl palmitate and β-carotene for the milk-fed lamb
Authors: Faruque O. , Walker D. M. 
Published: May 2005

1. Thirty-four cross-bred newborn lambs were used. A high-protein diet (25% protein calories) was supplemented daily with retinyl palmitate (range, 13.75–440 μg/kg live weight 24 h), or with β-carotene (range, 68.5–2200 μg/kg live weight 24 h) for 21 days.2. Live-weight gain was not increased by supplementing the basal diet with either retinyl palmitate or β-carotene.3. The relative weights of β-carotene and retinyl palmitate (expressed as retinol) that were required to produce equivalent concentrations of retinol in the serum varied from 5:1 to 25:1, and for the liver (retinal + retinyl esters, expressed as retinol) the ratio varied from 3:1 to 9:1.
The action of vitamin D on the degree of mineralization of bone tissue in rats given adequate amounts of calcium and phosphorus in the diet
Authors: Rasmussen P. 
Published: May 2005

1. The action of vitamin D on the degree of mineralization of the bone tissue of rats given a diet containing adequate amounts of calcium and phosphorus for 8 weeks has been investigated by quantitative microradiography. The method is described.2. There was a significant reduction in the growth of the vitamin D-deficient rats; the reduction was most marked in the females.3. Serum analysis showed a reduction in Ca, but P was unchanged. However, the Ca × P product was considered to be high enough to permit normal mineralization.4. The degree of mineralization of the cortical bone tissue increased significantly according to the distance from the epiphyseal plate. However, there were no significant differences between vitamin D-treated and vitamin D-deficient animals.5. It is concluded that vitamin D deficiency in rats does not prevent the formation of a bone matrix which can attain a normal degree of mineralization.
Observations on obese patients eating isocaloric reducing diets with varying proportions of carbohydrate
Authors: Hood Cathryn E. A. , Goodhart J. M. , Fletcher R. F. , Gloster Josephine , Bertrand P. V. , Crooke A. C. 
Published: May 2005

1. Diets containing 1000 kcal/day with varying proportions of carbohydrate (CHO) were fed to four women with simple obesity. The patients were given, in various sequences and for 8 days in each instance, diets in which 3, 6, 12, 25 or 50% of the calories were supplied by sucrose.2. No significant difference in the rate of weight loss was found when the diets of graded CHO content were fed and mean weight loss was 1.2 kg/week.3. The high-CHO diets were antiketogenic; there was no daily relationship between urinary ketones and sodium. The 25 and 50% CHO diets had a nitrogen-sparing effect.4. A 1000 kcal/day diet with about a third of the calories derived from CHO leads to a useful rate of weight loss and minimum changes in body chemistry. This finding may have implications in the long-term treatment of obesity.
Interrelationships between copper deficiency and dietary ascorbic acid in the rabbit
Authors: Hunt C. E. , Carlton W. W. , Newberne P. M. 
Published: May 2005

1. Copper deficiency was induced in growing rabbits and the effects of ascorbic acid supplementation were studied.2. Signs of Cu deficiency, including reduced growth, achromotrichia and alopecia, anaemia, and gross alterations in the bones of the forelimbs, developed most rapidly in those animals fed ascorbic acid.3. Microscopic lesions in ossification centres were seen only in bones of rabbits which hadm received the vitamin.4. Calcium and phosphorus contents of ash from cortical bone were not changed.5. Compared with the controls, the concentration of liver Cu decreased and that of iron increased (> 50%) in Cu-deficient animals.6. Cytochrome oxidase activity was reduced in liver and heart in Cu-deficient animals; this effect was accentuated in heart preparations from animals fed ascorbic acid.
Studies on magnesium in ruminant nutrition
Authors: Field A. C. 
Published: May 2005

1. The excretion of calcium and potassium in urine, milk and faeces by grazing monozygotic twin cows has been determined at intervals throughout four grazing seasons.2. In Expt I three sets of twins were used to study the variation within pairs in the excretion of Ca and K. It was found that the variation within pairs was non-significant and small, less than 5% of the overall mean, for all but one of the factors measured. The variation in urinary excretion of Ca within pairs was significant (P <0.05) in 1962.3. In Expt 2 the effects of lactation on the excretion of Ca and K by three sets of twins were studied over two grazing seasons. Only one of each of the twins was in milk at a time, each twin being in milk for one season.4. Lactation increased (P <0001) urinary and faecal Ca in 1964 but not in 1965. The concentrations of Cain the faeceswere lower (P <0.01) for lactatingthanfornon-lactating cows.5. Lactation increased (P < 0.001) the excretion of K in urine and faeces. Differences within pairs in faecal concentration were significant in 1964 (P <0001) and 1965 (P < 0.01), but the effect was not attributable to lactation.6. Significant differences between pairs were found for urinary Ca and K in 1964 (P < 0.05) and for the concentration of K in faeces in both years ( P < 001 or P < 0.001).7. In 1964 greatest total excretions of Ca were found in June and July and of K in May, whereas in 1965, although the differences between periods for Ca and K were significant (P < 0.001), there were no obvious seasonal trends.8. Mean intakes of Ca and K by the cows have been calculated from the estimated drymatter intake of herbage and the Ca and K content of the cut herbage and compared with total excretion in urine, milk and faeces. The differences between intake and excretion differed between periods (P < 0.001); for Ca, negative values were greatest in July and August in 1964 but not in 1965 and for K the values were small in July and large and positive in May, September and October in both years. The differences between lactating and non-lactating cows were significant for Ca(P < 0.001) and K (P < 0.01) in 1964. Selective grazing was considered to be the main factor responsible for these differences.
Utilization of14C-labelledBacillus subtilisandEscherichia coliby sheep
Authors: Hoogenraad N. J. , Hird F. J. R. , White R. G. , Leng R. A. 
Published: May 2005

1.Bacillus subtilisandEscherichia coliwere grown on14C-labelled glucose and used for the preparation of labelled whole cells, cell walls, cell contents and peptidoglycan.2. The radioactive samples were injected into the abomasum of sheep and the14C appearing in expired air, plasma glucose, urine and faeces was determined. Whole cells were also injected into the rumen and the incorporation of14C into volatile fatty acids was measured.3. All the bacterial preparations, including cell walls, were extensively digested and absorbed, Less than 15% of the radioactivity was recovered in the faeces.4. Up to 20% of the radioactivity injected was recovered in expired carbon dioxide with only 2.4–8.1% passing through the glucose pool.5. It has been calculated that under the conditions of the experiment 18.5 % of the total glucose entering the body pool of glucose in 24 h was derived from bacterial carbon.
Concentrations and metabolism of volatile fatty acids in the fermentative organs of two species of kangaroo and the guinea-pig
Authors: Henning Susan J. , Hird F. J. R. 
Published: May 2005

1. Contents from the fermentative organs of the kangaroo and guinea-pig were found to have concentrations of total volatile fatty acids ranging from 50 to 140 mM.2. In each instance acetic was the most abundant acid, followed by propionic, then n-butyric, Trace amounts of isobutyric, n-valeric and isovaleric acids were present.3. When studiedin vitro, tissue from the wall of each fermentative organ was shown to metabolize butyrate to ketone bodies. Acetoacetate was the major ketone body. The presence of acetate and propionate did not affect ketogenesis from butyrate.4. In the guinea-pig caecum most of the ketogenic activity resided in the mucosa.5. The upper colon of the guinea-pig was as active as the caecum in metabolizing butyrate to ketone bodies.6. For both the guinea-pig caecum and the kangaroo fermentative stomach, incubations with14C-labelled butyrate showed that the proportion oxidized to CO2was considerably less than that metabolized to ketone bodies.
Observations on the microbiology and biochemistry of the rumen in cattle given different quantities of a pelleted barley ration
Authors: Eadie J. Margaret , Hyldgaard-Jensen J. , Mann S. O. , Reid R. S. , Whitelaw F. G. 
Published: May 2005

1. Three heifers were changed from a diet of equal parts of hay and barley cubes (50:50 diet) to one entirely of barley cubes given in three equal feeds throughout the day. Feed intake was restricted to 80% of calculated appetite at the time of change and this percentage progressively decreased as the live weights of the animals increased.2. The change of diet had no significant effect on the volume of rumen fluid but the rate of outflow from the rumen was significantly lower on the barley diet than on the 50:50 diet.3. Animals on the restricted barley diet developed an exceptionally high rumen ciliate population and the bacterial population was shown by Gram films to include a number of organisms typical of roughage-fed animals. In culture, organisms of the genusBacteroideswere predominant but these appeared largely as cocco-bacilli in the Gram films. This microbial population was associated with a higher proportion of butyric acid than of propionic acid in the rumen fluid.4. Occasional fluctuations in ciliate populations occurred in all three heifers. Decreases in ciliate number were paralleled by increases in propionic acid and decreases in butyric acid but not necessarily by a fall in pH. Under these conditions Gram films showed increases in bacteriodes-type rods and in certain curved Gram-negative rods.5. Rumen ammonia concentrations were on average lower and showed a different diurnal pattern when ciliate numbers were reduced. Lactic acid concentrations were low and were not affected by the size of the ciliate population.6. When the three heifers were given the barley dietad lib. there was a decrease in rumen pH and a complete loss of rumen ciliates. The rumen bacterial population and the volatile fatty acid proportions were similar to those seen during decreases in ciliate number at the restricted level of intake. These changes also occurred in a fourth heifer which was changed fairly rapidly from the 50:50 diet to a restricted amount of the barley diet.7. Two steers which had never had access to roughage were changed fromad lib. to restricted intake of the barley diet and were later given an inoculum of rumen ciliates. The rumen microbial population and the pattern of fermentation so produced were similar to those found in the heifers on the restricted barley diet.8. Anomalous values were noted for total counts of rumen bacteria when free starch grains were present in the rumen fluid.9. It is concluded that large ciliate populations and high proportions of butyric acid can be produced in animals fed exclusively on a barley diet by suitable adjustment of the intake and the method of feeding. It is postulated that the ciliate population may be largely responsible for the high butyric acid concentrations.
Volatile fatty acid production in the rumen of cattle given an all-concentrate diet
Authors: Whitelaw F. G. , Hyldgaard-Jensen J. , Reid R. S. , Kay Moird G. 
Published: May 2005

1. Short-term in vitro incubations of whole rumen contents have been used to measure the rate of production of volatile fatty acids (VFA) in two heifers given a diet containing 85% barley and 15% protein-mineral-vitamin supplement. Daily intake of the diet was restricted to 5.1 kg which was given in three equal feeds. In one heifer (no. 794), VFA production was measured over a 24 h feeding cycle; in the other (no. 832), a single 6 h feeding period was examined.2. The feeding schedule outlined above was found in previous work to result in a major alteration in the rumen environment and in the end-products of rumen fermentation relative to findings in animals given the same diet ad lib. Some of these earlier observations have been confirmed and extended in the present work.3. In heifer 794, the rate of VFA production reached a maximum (52–62 m-moles/l. h) 15 minafter each feed and then declined steadily throughout the remainder of the feeding period. Consistent changes with time were observed in rumen pH and in the concentration of VFA and dry matter in rumen contents during each feeding period.4. Simultaneous measurements of rumen fluid volume and outflow allowed estimates to be made of VFA production and absorption in the entire rumen during each feeding period. In heifer 794, total VFA production amounted to 18.2 moles/day of which approximately 85 % was absorbed directly from the reticulo-rumen. On a caloric basis, total daily production accounted for 36. 5% of the digestible energy intake.5. In heifer 832 there were significant differences in the rate of VFA production and in rumen pH and VFA concentration between two sets of observations made some 8 weeks apart. These differences appeared to be related to changes in the rumen microbial population and particular to a marked alteration in the numbers of ciliate protozoa. The possible role of rumen ciliates in modifying both the rate of VFA production and the environment within the rumen is discussed.