bluuebunny/crossref_metadata_2025_split huggingface dataset:
The nutrition of the veal calf
Authors: Roy J. H. B. , Stobo I. J. F. , Gaston Helen J. 
Published: May 2005

1. Twenty-four bull calves consisting of fifteen Friesians and nine Ayrshires in a randomized block experiment were reared from birth on liquid diets offered ad lib. in two feeds daily to a slaughter weight equivalent to 22 % of mature cow weight of the breed.2. The three diets given after the calves had received 7 kg whole colostrum were (a) fresh liquid skim milk containing 0.1 % butterfat, (b) a ‘high-fat’ diet containing reconstituted spray-dried skim milk and 2.8 % margarine fat, and (c) the ‘high-fat’ diet for 14 d from birth followed by liquid skim milk. All calves received supplements of magnesium and iron, and vitamins A, D and E. Digestibility and balance trials were made on nine calves of each breed at both 4 and 10 weeks of age. Certain observations were made at slaughter.3. Dry-matter and gross energy intakes of calves given the skim-milk diet were greater than for those given the ‘ high-fat ’ diet. Daily weight gain, efficiency of food conversion, incidence of a high rectal temperature ( > 39.33°), mean rectal temperature and faecal dry-matter content were greater for the calves given the ‘ high-fat ’ diet. Age to slaughter and incidence of diarrhoea were much greater for the calves given liquid skim milk.4. Apparent digestibility of lactose and apparent absorption of ash and calcium were greater withthe ‘high-fat ’diet, but no difference occurred in apparent digestibility of dry matter or protein. Metabolic faecal fat excretion was estimated from the intercept of the relationship between apparently digested fat and fat intake for the calves given the liquid skim-milk diets; the values obtained ranged from 29 mg/kg live weight for Friesian calves at 10 weeks to 49.5 mg/kg for Ayrshire calves at 4 weeks. The true digestibility of the fat was estimated.5. No difference in Ca or nitrogen retention occurred between diets, but urinary N excretion and N retention/100 g gain in weight were markedly higher and concentration of N in the urine was much lower for calves given the skim milk.6. Perirenal fat deposition per unit of metabolic body size was 168 % greater for calves given the ‘ high-fat ’ diet. Kidney weight and skin weight were greater for the calves given the liquid skim-milk diet. The increased kidney weight was related to the very large urine output of the calves given skim milk.7. In comparison with Ayrshire calves, Friesian calves were much less susceptible to the adverse effects of liquid skim milk, having a lower incidence of diarrhoea and faeces of a higher dry-matter content, but they did have a higher incidence of lung lesions. Friesian calves also had a higher relative growth rate, efficiency of feed conversion, mean body temperature, faecal pH, apparent absorption of Ca, retention of N and Ca per unit of metabolic body size and killing-out percentage, but lower skin weight per unit of metabolic body size. Perirenal fat per unit of metabolic body size did not differ between breeds.
Incidence of protein deficiency in relation to different diets in India
Authors: Sukhatme P. V. 
Published: May 2005

1. A method is presented for estimating the incidence of protein deficiency which takes due note of the association of protein deficiency with inadequate calorie intake and is applied to the data from dietary surveys in India. It is concluded that in only about one out of ten cases does protein deficiency occur as a direct result of inadequate protein intake. In the vast majority of cases protein deficiency is the result of inadequate intake of total energy. Protein which does not bring calories with it is therefore unlikely to make any significant contribution to the solution of the protein problem in India.2. It is shown that diets based on cereals and pulses normally consumed by the people can meet man's needs for proteinat all ages provided enough food is taken to satisfy his energy needs. It is, however, important to ensure for infants a smooth transition from breast milk to solid diets. Special care is also necessary in the case of pregnant and lactating women.3. The nature of protein deficiency is discussed in relation to different dietary patterns. The continuity implied in the bivariate distributions of calorie and protein intake is seen to provide a possible explanation of the experimental results on the development of kwashiorkor observed in animals on a diet short of both calories and protein and ondietspredominantly short of protein.
Intermittent and continuous faecal markers in short-term metabolic balance studies in young women
Authors: Sharpe Susan J. , Robinson Marion F. 
Published: May 2005

1 The continuous faecal marker chromic oxide, Cr2O3, and the intermittent marker brilliant blue were used together in metabolic balance studies of calcium and magnesium in two young women.2. Faecal output was derived by four methods: no marker, brilliant blue, Cr2O3, or both brilliant blue and Cr2O3.3. Balances of Ca and Mg derived by the four methods of obtaining faecal output were compared.4. Recovery of ingested Cr2O3 in the faeces appeared complete in experiments on three further subjects, with only a negligible amount being excreted in the urine.5. Simultaneous use of both types of marker is recommended for short-term balance studies of nutrients such as Ca and Mg which are not readily absorbed.
Artificial rearing of pigs
Authors: Braude R. , Mitchell K. G. , Newport M. J. , Porter J. W. G. 
Published: May 2005

1. Pigs were weaned from the sow at 2 d of age and reared on a diet of cow's milk supplemented with vitamin D, and antibiotics. The effects of four levels and two frequencies of feeding, and the temperature of the environment were studied in relation to the performance of the pigs and the digestion of the milk protein. Pigs fed at the two lower levels receivedadiet of cow's milk, but at the two higher levels cow's milk was spray-dried and reconstituted to 20% total solids. A comparison was also made between cow's milk and spray-dried reconstituted milk, both fed hourly with 12.5% total solids. The pigs were slaughtered at 28 d of age.2. No differences in the nutritive value or digestion of the milk protein were found when cow's milk and reconstituted milk were fed with a total solids content of 12.5 yo.3. Increasing the level of feeding resulted in a faster growth rate, and some deterioration in the feed conversion efficiency. The growth rate of the pigs from 2to 28 d of age when fed at a high level greatly exceeded that of sucking pigs reared on the sow. The retention of the dietary nitrogen also improved with increased feed intake. A highly significant inverse linear correlation of N retention with age was found at all levels of feeding. The milk protein was efficiently digested at all levels of feeding.4. The mortality rate was very low but there appeared to be some association of losses with a high level of feeding during the first few days of life.5. Feeding hourly compared with feeding twice daily improved the feed conversion efficiency, although the effect on growth rate and N retention was small. The retention of digesta in the stomach appeared to be an important factor in the regulation of the amount of digesta in the small intestine and in the maintenance of digestive efficiency. The stomachs of pigs fed twice daily contained considerably greater amounts of digesta than those of pigs fed at hourly intervals. There was little difference in the amount and composition of digesta in the small intestine and caecum at either frequency of feeding.6. No differences were found in the performance of the pigs, N retention or the efficiency of digestion of the milk protein when the environmental temperature was maintained either at zoo throughout the experiment, or at 30' gradually reducing to zoo during the first 14d.
Calorie conversion factors. An experimental reassessment of the factors used in the calculation of the energy value of human diets
Authors: Southgate D. A. T. , Durnin J. V. G. A. 
Published: May 2005

1. The intake and excretion of total nitrogen, fat and the various forms of carbohydrate, and the heats of combustion of the diet, urine and faeces were measured in groups of young men, young women, elderly men and elderly women.2. Each group was studied while the subjects were eating two diets in turn, which differed in their contents of unavailable carbohydrate; the young women were also studied on a third diet which was rich in unavailable carbohydrate.3. Increasing the intake of unavailable carbohydrate resulted in a greater faecal loss of energy, and in most instances of nitrogen and fat.4. There was no significant effect of sex or age on the apparent digestibility of protein, fat or available carbohydrate.5. The results are used to evaluate the use of calorie conversion factors for calculating the metabolizable energy content of mixed diets.6. These show that for practical purposes the classical Atwater factors can be used to calculate the metabolizable energy of a diet with reasonable accuracy, provided that when available carbohydrate (as monosaccharides) values are used in the calculation a factor of 3.75 kcal/g (15.7 kJ/g) is used.7. The studies demonstrate that the accuracy of any method for calculating the metabolizable energy of a diet is largely determined by the accuracy with which the method is capable of predicting the gross energy of the diet.
Effects of dietary glycerol on the serum glyceride level of men and women
Authors: MacDonald I. 
Published: May 2005

1. The serum glycerides of men were raised 1–2.5 h after the ingestion of glycerol, whereas in young women given glycerol the serum glycerides were not raised. In men who had a supplementation of glycerol to their free-choice diet there was a rise in the concentration of fasting serum glycerides, a rise that was not found when a similar supplementation was given to young women.2. These findings would support the tentative suggestion that dietary fructose does not follow the Emden-Meyerhof pathway to the same extent as glucose. The increased serum glyceride levels reported after high-fructose diets may be due to an increased availability of the glycerol moiety of glycerides.
Nucleic acid metabolism in the ruminant
Authors: Smith R. H. , Mcallan A. B. 
Published: May 2005

1. Concentrations of nucleic acid nitrogen (NA-N) and other nitrogenous constituents were estimated in samples of rumen fluid taken from calves and cows which were either given stall diets of varying nitrogen content or were allowed to graze pasture. Concentrations of NA-N ranged from 1.5 to 27.5 mg/100 g water.2. Ratios of RNA: DNA in rumen fluid were similar to those in rumen bacteria and were not related to those in the diets. Pure nucleic acids added to the rumen were rapidly degraded. It was therefore concluded that NA-N in rumen fluid was largely of microbial origin and provided an index of total microbial nitrogen.3. In most experiments, with an individual animal consuming diets of various nitrogen contents, NA-N formed a fairly constant percentage (8-15 for different animals) of the total non-ammonia nitrogen in rumen fluid. This suggested that nitrogen entering the rumen fluid limited microbial growth. Consumption of a diet containing extracted decorticated groundnut meal (diet B), however, led to lower values for this percentage than did the other diets. Diet B was also exceptional in leading to marked diurnal variations in NA-N concentrations in rumen fluid, suggesting a cyclic fluctuation in the size of the microbial population.4. Comparison of NA-N:total nitrogen ratios in rumen fluid and bacteria suggested that, for all the diets except diet B, 55–80 and 40–50% of the non-ammonia nitrogen in rumen fluid was of microbial origin for the calves and cows respectively.
Changes in the concentration of specific amino acids in the serum of experimentally malnourished pigs
Authors: Grimble R. F. , Whitehead R. G. 
Published: May 2005

1. The concentrations of individual free serum amino acids have been studied during the course of chronic protein malnutrition in experimentally malnourished pigs.2. Until growth was markedly impaired, reducing the protein content of the diet had no significant effect on serum amino acid composition.3. During the period when growth had practically ceased but kcal intake per kg body-weight was normal the concentrations of valine, leucine, isoleucine, threonine and eventually tyrosine fell, the levels of alanine and serine were above control levels and aspartic acid, glycine, methionine, phenylalanine, proline, arginine, histidine and lysine remained unaltered.4. When the kcal intake per kg fell below control levels, owing to anorexia, and the animals began to lose weight, the levels of alanine, glycine, serine and methionine fell and valine, leucine, isoleucine, threonine and tyrosine remained well below control levels.5. The physiological, nutritional and metabolic significance of these findings is considered. The changes in alanine and glycine concentration are discussed in terms of the regulation of gluconeogenesis. The reduction of the branched-chain amino acids is interpreted on the basis of their availability for synthetic and catabolic needs.
The energy cost of human lactation
Authors: Thomson A. M. , Hytten F. E. , Billewicz W. Z. 
Published: May 2005

1. The energy values of the diets of twenty-three women who were breast-feeding and thirty-two who were bottle-feeding their babies were determined by 7 d weighed surveys. All the subjects were healthy and living at home, and their babies were thriving. The lactating mothers took, on average, 591 kcal (2.5 MJ)/d more than those who were not lactating.2. Both groups were losing weight, on average. The estimated contribution of such losses to the total energy supply was added to and the amounts expended on basal metabolism deducted from the dietary energy intakes. Since the activity of each group was fairly similar, it was possible to conclude that the average amount of energy available to support lactation was 618 kcal (2.6 MJ) daily. The average energy value of the milk produced was estimated from the weights of the babies to be 597 kcal (2.5 MJ) daily.3. Critical evaluation of those averages, and of the assumptions on which they were based, led to the conclusion that the energy exchanges in human lactation have an efficiency of 90% or more, with a lower limit of about 80%.4. The additional supply of 600 kcal (2.5 MJ) in the daily diet should suffice to support lactation and a ‘round figure’ of 500 kcal (2.1MJ) daily may be regarded as reasonable in official recommended allowances.
An investigation of the hyperaminoaciduria in phenylketonuria associated with the feeding of certain commercial low-phenylalanine preparations
Authors: Clayton Barbara E. , Heeley A. F. , Heeley Mary 
Published: May 2005

1. Hypertryptophanaemia, hypertryptophanuria and to a lesser degree a generalized hyperaminoaciduria were observed in phenylketonuric patients receiving certain commercial low-phenylalanine diets containing DL-tryptophan.2. The generalized hyperaminoaciduria was associated with the ingestion of acid hydro-lysates of protein, but not with the ingestion of enzymic hydrolysates or D-tryptophan.3. Alanine recovered from the urine of these treated patients had a D-isomer content of approx. 50%. This amount of urinary D-alanine could be derived from the ingestion of an acid hydrolysate of protein in which the amino acids had racemized to the extent of 2–3%.
The absorption and distribution of the naturally occurring tocochromanols in the rat
Authors: Pearson C. K. , Barnes M. McC. 
Published: May 2005

1. Groups of female albino rats were given 12–20 mg of one of the eight known toco-chromanols in 0.2 ml arachis oil by stomach tube, and were killed 2, 4, 8, 16 or 24 h afterwards. The liver, spleen, heart, kidneys, brain, small intestine and a portion of striated muscle were removed from each rat and analysed for the tocochromanol given.3. Maximum levels of the tocochromanols occurred in most tissues 4–8 h after dosing. In the liver the tocopherols were more efficiently absorbed than were the corresponding toco-trienols. In kidney, heart and muscle the percentage uptake of the tocotrienols was often greater than that of the corresponding tocopherols.
Synthesis of microbial protein from ammonia in the sheep's rumen and the proportion of dietary nitrogen converted into microbial nitrogen
Authors: Pilgrim A. F. , Gray F. V. , Weller R. A. , Belling C. B. 
Published: May 2005

1. The extent to which ammonia-N (NH3-N) serves as a starting point for synthesis of microbial nitrogenous compounds was assessed when 15N as (15NH4)2SO4 was continuously infused into the rumen of a sheep for periods of 78–98 h. Steady states were reached in the composition of the rumen contents because the animal was fed equal parts of its ration at hourly intervals. Concentrations of 15N in bacterial-N, protozoal-N and rumen NH3-N were compared.2. In two trials with a low-N diet consisting largely of wheaten hay the 15N concentration in bacterial N was 76 and 78% of that in the NH3-N. For protozoa the values were more variable —64 and 43%.In two trials with a higher-N diet (lucerne hay), the corresponding values were lower—bacterial-N 62 and 64%, protozoal-N 41 and 35%.It was concluded that synthesis of microbial protein was more dependent on ammonia as a starting point with the low-N diet than with the higher-N diet.3. Entry and exit rates for ammonia into and out of the rumen system were determined, and the results, in combination with those obtained for bacterial-N in the first part of the work, allowed calculations to be made of the production of microbial-N/d formed from NH3-N, and this in turn allowed calculation of minimal values for conversion of plant-N to microbial-N in the lumen. Minimal extent of conversion was 68% for the low-N diet and 53–55% for the higher-N diet.4. Total production of microbial-N in relation to the amount of N given was also calculated by using previously reported values for the relative proportions of protozoal-N and bacterial-N in sheep given diets similar to those used here. These values for extent of conversion were 73% for the low-N diet and 58–59% for the higher-N diet.
Copper deficiency in chicks: effects of ascorbic acid on iron, copper, cytochrome oxidase activity, and aortic mucopolysaccharides
Authors: Hunt C. E. , Landesman Joanne , Newberne P. M. 
Published: May 2005

1. Copper deficiency was induced in newly hatched chicks by feeding on a milk-based diet for 12 d; effects of supplementation with ascorbic acid were studied.2. Cu deficiency alone resulted in 30% mortality from aortic rupture. This was associated with a 20% increase in total acid mucopolysaccharides in the aorta, manifested as an increase in chondroitin sulphate and a relative decrease in hyaluronic acid. Cytochrome oxidase activity of liver and heart was less than half that of the controls.3. Supplementing the Cu-deficient diet with 0.5 % L-ascorbic acid increased mortality to 40%, raised total aortic acid mucopolysaccharides to a higher level, and increased liver iron by 36%.4. Supplementing the control diet with ascorbic acid decreased liver Cu by 30% and significantly reduced total aortic acid mucopolysaccharides.5. The enhancement of the Cu-deficiency effect by ascorbic acid probably results from interactions between ascorbic acid and absorption or metabolism of Cu; untoward effects of supplementing the control diet with ascorbic acid may be interpreted as manifestations of ascorbic acid toxicityper se.
The requirement of sheep for cobalt or for vitamin B12
Authors: Marston H. R. 
Published: May 2005

1. Sheep confined topens and given a cobalt-deficient ration which supplied about 30μgCo/d required for maintenance of normal growth rate a Co supplement approaching 40 μg administered per os daily; for maintenance of what appeared, under the conditions of the experiments described, to be the maximum vitamin B12 status of a sheep, namely 3 ng vitamin B12/ml serum and 1.4 μg vitamin B12/g liver tissue, a supplement of between 0.5 and 1.0 mg Co/d per os was necessary.2. For maintenance of normal growth rate the minimum daily requirement for vitamin B12 of sheep given the Co-deficient diet was about 11μg: about 5 μg absorbed from the gut and about 6 μg injected parenterally.3. Extrapolation of the linear regression obtained by plotting the amount of vitamin B12injected/d against concentration of vitamin B12 in the liver tissue of a sheep indicated that to attain a concentration of 1.4 μg vitamin B12/g liver (wet weight) injection of 34 μg vitamin B12/d was necessary.4. Comparison of the relative effects on body-weight of the administration of 100 μg vitamin B12/dper os and 3.12 μg vitamin B12/d by injection to sheep given the Co-deficient diet indicated that the efficiency of absorption of the vitamin from the gut was < 3%.5. Loss of appetite, the first symptom of vitamin B12 deficiency to appear in the sheep, occurred when the concentration of vitamin B12 in the liver was reduced to about 0.1 μg/g wet weight.6. In sheep given a supplement of 1 mg Co/d per os neither production in the rumen nor absorption from the gut but rather capacity for storage limited the concentration of vitamin B12 in the liver.7. Following treatment to restore the vitamin B12 status of a sheep whose stores of the vitamin had been depleted, there was a linear negative correlation between the increase in the concentration of vitamin B12 in the liver and the concentration prior to treatment.8. Following withdrawal of treatment from a sheep whose stores of vitamin B12 were adequate, there was a linear positive correlation between the rate of depletion of vitamin B12 from the liver and the concentration prior to cessation of treatment.9. The concentrations of vitamin B12 in the serums of sheep given the Co-deficient diet, and given a supplement of 1 mg Co/d per os 0.5 h after feeding, remained relatively stable over the period 0–7 h after feeding; maximum concentration occurred 7–8 h after feeding.10. Under the conditions of the experiments described a significant linear regression existed between concentration of vitamin B12 in the liver of a sheep and the logarithm of the concentration in the serum.
Effect of riboflavine deficiency on incorporation in vivo of [14C]amino acid into liver proteins of rats
Authors: Chatterjee Ajay K. , Jamdar S. C. , Ghosh B. B. 
Published: May 2005

1. The effect of riboflavine deficiency on in vivo incorporation of [2–14C]glycine into proteins of liver homogenates and its subcellular fractions has been studied on rats maintained on a 16 % protein diet.2. Riboflavine deficiency did not seem to affect the in vivo incorporation of [2–14C]g1ycine into proteins of liver homogenates. But riboflavine deficiency caused increased and reduced invivo incorporation of [14C]amino acid into mitochondrial and microsomal proteins, respectively.There was no significant change in the in vivo incorporation of [14C]amino acid into proteins ofnuclear, ribosomal and soluble fractions in riboflavine deficiency.3. Riboflavine deficiency caused enhanced and reduced proportions of liver mitochondrial and microsomal proteins, respectively.4. The results are discussed as suggestive of enhanced and reduced protein synthesis in the mitochondrial and microsomal fractions, respectively, of riboflavine-deficient rats.