bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of soya-bean protein on meat iron solubility and absorption in rats
Authors: Latunde-Dada G. O. , Neale R. J. 
Published: September 2005

1. Soya-bean proteins were used to replace 30 and 50% of the protein from 59Fe-labelled pigeon (Columbn L.) and chicken meat, and the solubility of the meat 59Fe in vitro and its absorption in vivo in rats in the presence and absence of soya-bean proteins were measured.2. Replacement of part of the chicken meat by soya-bean proteins reduced 59Fe solubility from chicken meat at all stages during simulated in vitro digestion.3. 59Fe absorption from 59Fe-labelled chicken meat when given to both Fe-replete and Fe-deficient rats was reduced in the presence of soya-bean proteins but was unaffected by the presence of casein or bovine serum albumin. 59Fe-absorption from pigeon meat in the presence of soya-bean proteins was not reduced to the same extent as that from chicken meat.4. There was no significant effect of soya-bean proteins on 59Fe-labelled haemoglobin Fe absorption in vivo in Fe-replete rats.5. Absorption of 59Fe from the isolated haemoproteins from chicken meat was unaffected by soya-bean proteins but 59Fe absorption from the main non-haem-Fe fractions was strongly inhibited, particularly from haemosiderin.
The effect of riboflavin deficiency on methylenetetrahydrofolate reductase (NADPH)(EC1.5.1.20) and folate metabolism in the rat
Authors: Bates C. J. , Fuller N. J. 
Published: September 2005

1. Riboflavin deficiency at two levels of severity was produced in weanling rats by feeding deficient diets for 6 weeks and using neck collars to prevent coprophagy. The severity of deficiency was monitored by growth, liver flavin levels and the activation coefficient of erythrocyte glutathione oxidoreductase (NAD(P)H) (EC 1. 6. 4. 2 ) Control groups, receiving the same diet with ample added riboflavin, were fed eitherad lib., or were pair-fed with the deficient animals.2. The hepatic flavoenzyme, methylenetetrahydrofolate reductase (NADPH) (EC 1.5.1.20), was very markedly affected by severe riboflavin deficiency and was significantly, but less markedly, affected by the intermediate level of deficiency. This reduction in activity was due primarily to the direct effect of the diminished supply of riboflavin, and occurred to only a small extent as a result of inanition, demonstrated by a moderate reduction in activity in the more severely food-restricted of the two pair-fed groups. Since the enzyme is assayed in the presence of its flavin cofactor, FAD, it clearly cannot be reactivated in vitro, as some other depleted flavoenzymes can. The discriminatory ability in distinguishing between severe and moderate riboflavin deficiency in vivo confers some potential advantages on this oxidoreductase as a possible index of riboflavin status.3. The hepatic activity of another key folate-metabolizing enzyme, dihydrofolate reductase (EC 1.5.1.3), was not diminished by riboflavin deficiency in the present study.4. The ratio, labelled 5-methyltetrahydrofolic acid: other labelled compounds derived from intraperitoneally injected pteroylglutamic acid in extracts of hepatic tissue was significantly reduced in the riboflavin-deficient groups, indicating the possibility of an effect of riboflavin deficiency on folate metabolism in vivo.
The degradation of guar gum by a faecal incubation system
Authors: Tomlin J. , Read N. W. , Edwards C. A. , Duerden B. I. 
Published: September 2005

1. Homogenized and diluted faeces (50 g/l) from one human source were incubated with the complex plant polysaccharide, guar gum, to investigate the degradation of viscous polysaccharides by intestinal bacteria.2. Incubation of the faecal homogenate with guar gum produced a rapid decrease in viscosity and in pH, accompanied by the release of hydrogen.3. No changes in viscosity or pH were observed and there was no production of H2gas when guar gum was incubated with autoclaved faecal homogenate (20 min, 1.03 × 105Pa).4. A bacteria-free filtrate of faeces was prepared by centrifuging the faecal homogenate (2400 g for 100 min) followed by filtration through a Seitz filter and then a millipore filter (size 0.45 μm). Incubating this with guar gum produced a slow decrease in viscosity, but no significant change in pH and no generation of H2.5. Our results show that guar gum can be fermented by human colonic bacteria and suggest the possibility of predigestion by extracellular free enzymes.
The effect of dietary fibre isolates on gastric secretion, acidity and emptying
Authors: Tadesse K. 
Published: September 2005

1. In six volunteers, the effect of intragastric administration of different water-soluble chemical isolates of dietary fibre on gastric secretion, acidity and emptying was studied.2. At 30 min after administration of the test meals, the stomach contents were completely aspirated and the volume, pH, phenol red concentration, total titratable acidity and different electrolytes were measured.3. Compared with the control meal, the pH and unionized (combined) hydrogen concentrations were significantly higher (P < 0.05) following most of the fibre-containing meals, while the total titratable acid concentration was not significantly different. None of the fibre-containing meals appreciably altered the volume or type of gastric secretion but had a low-grade variable effect on gastric emptying.4. It is concluded that most dietary fibre isolates, although having a definite and notable buffering effect on the acid in the stomach, have a minimal effect on gastric secretion and a variable and small effect on gastric emptying.
Nutrition and cellular immunity in hospital patients
Authors: Dowd Pauline S. , Kelleher J. , Walker B. E. , Guillou P. J. 
Published: September 2005

1. The interrelations between nutritional and ccllular immune function measurements were studied in seventy patients suffering from various degrees of malnutrition. They included patients with liver disease, inflammatory bowel disease, neoplastic disease, neurological patients, post-operative surgical patients and patients with respiratory problems.2. Nutritional measurements included: anthropometry, serum proteins, various vitamins and trace elements, and a prognostic nutritional index (PNI) was calculated.3. Immunological measurements included: (1) natural killer (NK) cell activity, (2) antibody-dependent cellular cytotoxicity (ADCC), (3) lymphocyte proliferation in response to the mitogens concanavalin A (Con A), phytohaemagglutinin (PHA) and pokeweed mitogen (PWM) in both AB and autologous serum.4. There was no association between anthropometric measurements and tests of immune function.5. The lymphocyte proliferation in response to mitogenic stimulation in the malnourished patients was depressed in autologous serum compared with the response of the same lymphocytes in pooled AB serum. The lymphocyte proliferation in response to Con A correlated with transferrin in autologous serum (r0.46,n49,P< 0.0 I ) and to a lesser extent in AB serum (r0.33,n51,P< 0.05). There was a difference in the Con A-stimulated tritiated-thymidine uptake between patients with low and normal serum zinc levels (P< 0.05) for cultures performed in autologous serum, but not AB serum.6. There was a significant correlation between NK cell activity and vitamin C (r0.43,n60,P< 0.01). There was no relation between nutritional measurements and ADCC or the lymphocyte response to stimulation with PHA or PWM.7. The results suggest that the severity of overall malnutrition does not influence several different aspects of the cellular immune response. However, the results do suggest that certain individual nutrients, particularly vitamin C and Zn, do influence the immunoreactivity of different lymphocyte subpopulations.
The nitrogen and energy metabolism of lactating cows given abomasal infusions of casein
Authors: Whitelaw F. G. , Milne J. S. , Ørskov E. R. , Smith J. S. 
Published: September 2005

1. Four cows in early lactation were given continuous infusion into the abomasum of 0, 200, 400 or 600 g lactic casein/d according to a Latin-square design. Each period was of 14 d and the Latin square was followed by 7 d in which an infusion of 800 g glucose/d was given. The basal diet was given at a level which provided sufficient nitrogen and energy for 10 kg milk yield/d.2. Infusion of casein resulted in significant increases in milk yield, milk N yield and milk energy yield; milk N increased progressively but milk energy reached a maximum at 400 g casein/d. Milk yields and composition when glucose was infused resembled those seen on the zero casein treatment.3. N-balance measurements indicated a severe deficit (–20 g/d) on the zero casein treatment and a progressive increase to +7 g/d as casein increased; N equilibrium was achieved at about 400 g casein/d. The regression of net productive N on N intake (P< 0.001) indicated that the efficiency of utilization of dietary N did not differ between treatments.4. Heat production increased with increase in casein infused (P< 0.05) but remained a constant proportion of the metabolizable energy (ME) intake. Energy balances were negative and did not differ significantly between treatments but calculation of the protein and fat components indicated a threefold increase in body fat mobilization in response to the first increment of casein. Milk yield adjusted to zero energy balance was significantly related to ME intake (P< 0.001) but the efficiency of encrgy utilization was not affected by the level of casein infusion.5. The concentrations of glucose, β-hydroxybutyrate and non-esterified fatty acids in plasma did not differ between treatments but the concentration of urea in plasma increased markedly (P< 0.05) at the highest level of casein addition. Insulin concentrations increased and growth hormone decreased (bothP< 0.05) with increase in casein infusion.6. The concentration of total amino acids (AA) in plasma increased up to 400 g casein/d and then declined. Changes in concentration and in the ratio of essential: total AA indicated a very high extraction rate of essential AA at the lower levels of casein infusion.7. The observed lactational responses are discussed in relation to the ratio of protein:energy in the absorbed nutrients. It is concluded that the primary response to casein was the correction of an AA deficit and that body fat mobilization was secondary and occurred in response to the high ratio of AA-N:energy in the infused casein.
Nitrogen transactions in the digestive tract of lambs exposed to the intestinal parasite, Trichostrongylus colubriformis
Authors: Poppi D. P. , Macrae J. C. , Brewer A. , Coop R. L. 
Published: September 2005

1. Ten 5-month-old lambs (29 (SE 1.2) kg), reared parasite-free and prepared with rumen duodenal and ileal cannulas, were paired and given rations of Ruminant Diet AA6 (90 g/kg live Weight0.75) by means of continuous feeders. From 6 months of age one of each pair was dosed daily with 2500 Trichostrongylus colubriformis larvae for 14 weeks. Untreated animals received the amount of ration consumed by their infected pair-mates the previous day.2. During three periods, ((1) the week before and the first 2 weeks of dosing with infected larvae, (2) during weeks 5–7 and (3) during weeks 11–13 of dosing) all lambs underwent a series of experiments to determine their nitrogen balance, the amounts of N leaving the small intestine, the amount of 51CrC13-labelled plasma protein leaking into the small intestines, and the disappearance of 35S-labelled bacteria from the small intestine.3. The infection caused varying degrees of feed refusal in all infected animals. As a result the values for N balance and for the flow of N at the ileum during the latter two periods were regressed against dry-matter intakes for each group in each period.4. The infection caused a reduction (P < 0.05) in N retention and increased (P < 0.05) flow of N at the ileum. The increase in N flow at the ileum of infected lambs was greater (P < 0.01) at weeks 11–13 of dosing (infected–control 3.6 g N/d (standard error of difference (SED) 0.57), P < 0.01) than at weeks 5–7 of dosing (infected–control 1.5 g N/d (SED 0.57), P < 0.05).5. There were no between-treatment or between-period differences in the disappearance of 35S-labelled bacteria from the small intestines of infected or control lambs, but the infection did cause an increase in plasma N leakage during both periods. During weeks 5–7 and 11–13, plasma N leakage in infected lambs was 1.1 g N/d (P < 0.01) and 1.7 g N/d (P = 0.056) respectively higher than that in the control lambs.6. A proportion of the endogenous secretions which enter the small intestine is likely to be resorbed before the ileum. It was calculated that to account for the extra non-ammonia-N (NAN) flow at the ileum up to 3–5 g NAN/d during weeks 5–7 of dosing and 15–20 g N/d during weeks 11–13 of dosing could have entered the small intestine as mucin and sloughed cells.7. The results seem to indicate that the nutritional penalty associated with the development of resistance to infection is greater than that associated with the primary infection.
Experimental zinc deficiency in guinea-pigs: biochemical changes
Authors: Gupta R. P. , Verma P. C. , Gupta R. K. Paul 
Published: September 2005

1. Zinc deficiency was produced experimentally in guinea-pigs fed on a diet containing 1.25 mg Zn/kg diet over a period of 60 d. In addition, the response of the Zn-deficient (ZnD) animals to Zn supplementation was studied for 15 d.2. In the ZnD group a significant reduction was found in serum Zn and protein concentrations and in alkaline phosphatase (EC3. 1. 3. 1; AP) activity from day 24 onwards.3. Paper electrophoretic studies on serum revealed a significant decrease in relative values, as well as absolute values, of albumin and γ-globulin and an increase in β-globulin.4. Albumin:globulin increased on day 24 but decreased significantly from day 48 onwards.5. The kidney and testis of the ZnD group showed a reduction in Zn and protein contents, and AP activity.6. Zn supplementation of the previously ZnD group resulted in marked although incomplete improvement in the biochemical indices studied.
The significance of carbon dioxide and methane measurements in the estimation of heat production in cattle
Authors: Mclean J. A. 
Published: September 2005

1. Records of metabolic measurements on cattle by open-circuit indirect calorimetry have been examined to determine the practical significance in the calculation of heat production of including measurements of carbon dioxide and methane in addition to the measurement of oxygen.2. It was found that the combined effects of CO2 and CH4 made only a small contribution to the total estimation of heat production which could be calculated with approximately ± 1 % accuracy from analysis of O2 alone.
Enhanced whole-body protein synthesis by methionine and arginine supplementation in protein-starved chicks
Authors: Muramatsu T. , Kato M. , Tasaki I. , Okumura J. 
Published: September 2005

1. The effect of supplementing with methionine alone or in combination with arginine on whole-body protein synthesis and degradation was studied in protein-starved chicks, fed on a protein-free (PF) diet, by a massive-dose injection of L-[4-3H]phenylalanine.2. Methionine or methionine and arginine (MA) supplementation reduced body-weight loss and improved N balance compared with unsupplemented controls.3. Whole-body protein synthesis was significantly increased both in terms of fractional rate and absolute amounts by methionine and MA addition, whereas the fractional degradation rate was unchanged.4. No significant difference was found between methionine and MA supplementation except for energy balance of the birds.5. It was concluded that the N-sparing effect of methionine or MA when added to a PF diet was primarily brought about by enhanced whole-body protein synthesis.
Yield and nutrient content of milk in eight women breast-feeding twins and one woman breast-feeding triplets
Authors: Saint L. , Maggiore P. , Hartmann P. E. 
Published: September 2005

1. The milk yield of eight mothers each breast-feeding twins was determined by test weighing the mothers. Milk yield was determined at 2, 3, 6, 9, and 12 months post partum; however, only one mother was studied at all these times.2. At 6 months post partum the milk yield for individual breasts of three mothers fully breast-feeding and four mothers partially breast-feeding their infants ranged from 0.84 to 2.16 kg/24 h and 0.42 to 1.39 kg/24 h respectively. The average frequency of breast-feeding for the mothers studied at 6 months post partum was 15.4 feeds124 h.3. The milk yield of one mother fully breast-feeding 2.5-month-old triplets was 3.08 kg/24 h and the infants were fed twenty-seven times in 24 h.4. The concentration of lactose, protein and mixed fat in the milk from individual breasts of mothers fully breast-feeding their infants ranged from 65.6 to 82.2, 7.8 to 15.7 and 16.7 to 46.2 g/1 respectively. For the three mothers partially breast-feeding 12-month-old infants the values ranged from 54.8 to 71.8, 14.2 to 19.9 and 4.7 to 40.5 g/l respectively.5. At 6 and 12 months of age, the proportion of the total energy intake of the infants which was derived from breast milk ranged from 64 to 100% and 6 to 13% respectively.6. It is concluded that the maximum potential milk yield for women may be higher than the often quoted value of 70–800 m1/24 h.
Effects of adrenalectomy before weaning in the genetically obese Zucker rat (fa/fa)
Authors: Fletcher J. M. 
Published: September 2005

1. Lean (Fa/?) and obese (fa/fa) Zucker rats were adrenalectomized or sham-operated at 19 d of age (3 d before weaning). Injection of corticosterone for 3 d after weaning (1.0 mg/d) was necessary to ensure survival of adrenalectomized fa/fa but not Fa/? rats. Intact and adrenalectomized fa/fa rats had a lower rectal temperature than Fa/? animals before and 3 d after adrenalectomy. The post-weaning survival of adrenalectomized fa/fa rats was enhanced by maintenance at an ambient temperature of 30° rather than 22°.2. Adrenalectomized and sham-operated rats were therefore kept at 30°, fed ad-lib. and killed at 34 d. Adrenalectomy had only small effects on the growth, body composition and appetite of Fa/? rats. The hyperphagia, greater lipid content, reduced protein content and hyperinsulinaemia of fa/fa rats were completely abolished by adrenalectomy.3. Intact fu/fa rats had higher liver glycogen contents and higher activities of the hepatic enzymes tyrosine aminotransferase (EC 2. 6. 1. 5) and acetyl CoA carboxylase (EC 6. 4. 1. 2) than intact Fa/? animals. Adrenalectomy abolished these phenotypic differences.4. Injection of adrenalectomized rats with 1.0 mg corticosterone-21-acetate daily from weaning to 34 d restored the abnormal body composition, hyperphagia, hyperinsulinaemia, higher hepatic glycogen and enzyme activities of fa/fa rats.5. In a second experiment adrenalectomized rats were injected with 1.0 mg corticosterone-21-acetate daily from weaning to 34 d and kept at 22°, fa/fu rats adrenalectomized and injected with corticosterone had a reduced body lipid content compared with intact fa/fa rats but still contained more lipid than intact or similarly treated Fa/? animals.6. In both experiments adrenalectomized Fa/? and fa/fa rats injected daily with corticosterone had the same plasma concentrations of this hormone when killed 3 h after the last injection at 34 d. It is concluded that corticosterone is required for expression of the abnormal appetite, hyperinsulinaemia and body composition of the fa/fa rat.
Effects of sodium intake on lactation and Na levels in body fluids of Blackface ewes
Authors: Vincent Isobel C. , Williams H. Ll. , Hill R. 
Published: September 2005

1. A low-sodium diet was given to Blackface ewes over two reproductive seasons; the diet provided 3–7 mmol Na daily, except for the period of lactation, when Na intake was increased to around 11 mmol/d. The diet of the control ewes was supplemented with sodium chloride to provide the recommended allowance of about ten times the level in the experimental low-Na diet.2. Milk production was assessed during the first 2 months of lactation from incremental changes in the live weight of lambs during controlled sucking periods. Na and potassium were determined in milk and also in plasma, saliva and urine.3. Neither yield nor concentration of Na and K in milk was affected by the level of Na in the diet. These results were supported by the similarity in live-weight gain of lambs in both years regardless of diet.4. Plasma Na and K concentrations were not affected by the level of dietary Na. Na concentration in saliva and urine was significantly lower in the treated than in the control ewes, and K concentration in saliva was significantly higher.
Determination of digestible and available amino acids in meat meal using conventional and caecectomized cockerels or chick growth assays
Authors: Parsons Carl M. 
Published: September 2005

1. The present study was designed to compare true digestible amino acid values for meat meal with available amino acid values. True digestible values were determined with a 48 h excreta collection assay using conventional (CONV) and caecectomized (CEC) cockerels. Available values for lysine, methionine and cystine were estimated by chick growth assays.2. True digestibilities of all sixteen measured amino acids (expressed as a proportion of the total) were lower for CEC than for CONV cockerels, with the average difference being approximately 0.10.3. Chick growth assays based on total weight gain indicated that the availabilities of amino acids expressed as a proportion of the total amino acids in meat meal were: 0.70 for lysine, 0.75 for methionine and 0.48 for cystine. Partitioning weight gains to reflect only growth attributable to supplemental crystalline amino acid or meat meal intake consistently yielded higher availability values than when total weight gains were used.4. True digestibility values determined with CEC cockerels were in better agreement with chick available values than were true digestibility values determined with CONV cockerels.5. The amounts of amino acids present in the caeca of meat meal-fed CONV cockerels at 48 h after feeding were small when compared with those levels voided in the excreta and those levels consumed in the feed.6. Multiple regression analyses of excreta and caecal amino acid profiles at 12 and 48 h after feeding suggested that significant amounts of non-digested dietary amino acids flowed into the caeca and were subsequently metabolized by the caecal microflora.
Stimulation of muscle growth by clenbuterol: lack of effect on muscle protein biosynthesis
Authors: Reeds Peter J. , Hay Susan M. , Dorwood Patricia M. , Palmer Robert M. 
Published: September 2005

1. Young rats were offered to appetite a semi-synthetic diet either alone or containing the β2-selective agonist clenbuterol (4-amino-α[t-butylamino) methyl]-3, 5-dichlorobenzyl alcohol).3. Male rats (starting weight 53 g) received clenbuterol at a daily oral dose of 200 pg/kg body-weight per d. Animals were slaughtered after 0, 4, 8, 11, 18, 21 and 25 d of treatment. At 4, 11, 21 and 25 d muscle protein synthesis was measured by the method of Garlicket al.(1980). Although clenbuterol increased the rate of protein and RNA accretion in gastrocnemius and soleus muscles, protein synthesis was not increased.4. The results suggested that the drug had a rapid, perhaps direct, inhibitory effect on protein degradation. It is concluded that the growth-promoting effect of clenbuterol may be specific to muscle and that the drug may act in a novel manner which circumvents the physiological mechanisms responsible for the control of muscle growth.