bluuebunny/crossref_metadata_2025 huggingface dataset:
A model for zinc metabolism in sheep given a diet of hay
Authors: Suttle N. F. , Davies H. Lloyd , Field A. C.
Published: May 2005

1. Four pairs of Scottish Blackface ewes were given a basal diet of hay, providing 8 mg zinc/d, and one of four levels of supplementary Zn (0, 75, 150 or 225 mg/d) continuously by intraruminal infusion.

2. 65Zn (59 μCi) was given intravenously after stabilization for 14 d and the changes in specific radioactivity (SR) of plasma and faeces were monitored for a further 10 and 13 d respectiveiy. The faecal endogenous losses and absorption of Zn were estimated, using the principle of isotope dilution, by two methods using the whole or latter parts of SR: time curves.

3. Faecal endogenous losses were estimated by the part area method to be 4·9, 6·4, 5·1 and 6·3 ± 0·35 mg/d at 0, 75, 150 and 225 mg supplemental Zn/d i.e. largely unaffected by Zn intake and averaging 0·11 mg/kg live weight (LW). The whole area method gave similar results.

4. Urinary excretion was negligible (probably < 0·2 mg/d) for all sheep.

5. The amount of Zn absorbed was assumed to equal the irreversible loss of Zn under steady-state conditions and found to remain constant at 7·6±0·39 and 10·3±0·6 mg/d when calculated by ‘whole’ and ‘part area’ methods. Zn retention did not increase with Zn intake and homoeostasis was achieved primarily by control of Zn absorption which fell from 0·75 to 0·03 or from 0·96 to 0·05 of intake, depending on method of calculation, as intakes increased.
Ingestion of iron in sow's faeces by piglets reared in farrowing crates with slotted floors
Authors: Gleed P. T. , Sansom B. F.
Published: May 2005

1. Two sows were housed in farrowing crates with slotted floors and fed daily with approximately 200 μCi 198Au from 3 d before farrowing until their piglets were 21 d old.

2. The sows' faeces became radioactive but their milk remained free of radioactivity. The piglets' mean (±SE) whole-body radioactivity was equivalent to 8·5 ± 0·9 g (range 3·8–15·5 g) of faeces. This is probably a measure of their daily intake of faeces.

3. The possibility of using this natural coprophagia to prevent piglet anaemia has been demonstrated on two commercial piggeries by feeding the sows a diet containing 2000 mg Fe/kg.
The effect of long-term feeding of soya-bean flour diets on pancreatic growth in the rat
Authors: Crass Rosa A. , Morgan R. G. H.
Published: May 2005

1. Pancreatic growth was measured in rats by changes in pancreatic weight, nucleic acid content and protein content after feeding diets of heated soya-bean flour (HSF), raw soya-bean flour (RSF), 200 g raw soya-bean flour+800 g heated soya-bean flour/kg (80 HSF) and 400 g raw soya-bean flour+600 g heated soya-bean flour/kg (60 HSF) for periodsup to 36 weeks. Control rats of comparable age to soya-bean flour-fed rats were continuedon rat cubes during the 36-week study.

2. Cube-fed rats remained significantly heavier than rats fed on soya-bean flour diets. Analysis of variance showed rats fed on HSF were significantly heavier than RSF-fed rats and rats fed on 80 HSF significantly heavier than those fed on 60 RSF.

3. Pancreatic indices in HSF-fed rats were similar to comparable control rats.

4. Hypertrophy was found in rats fed on the RSF-containing diets with the extent of enlargement corresponding to the RSF content. Hyperplasia was also found in rats fed on RSFand 60 HSF.

5. The greatest pancreatic growth was seen in RSF-fed rats with all the indices peaking at 8 weeks followed by a decline and then a rise again at 36 weeks.

6. The fall in pancreatic indices in rats fed on RSF for 12 and 24 weeks is most likely an effect of general malnutrition due to the multiple deficiences in amino acids which occur in animals fed on RSF. The rise at 36 weeks may reflect increased body growth or the beginning of adenornatous changes.
The availability to the chick of pantothenic acid in foods
Authors: Latymer Eva A. , Coates Marie E.
Published: May 2005

1. The content of total pantothenic acid (PaA) in two foodstuffs of microbial origin was measured by standard microbiological and chick biological assays.

2. Substantially and consistently higher values were found by the chick assay than by the microbiological determination, indicating that PaA-containing compounds were present that were not utilized by the test micro-organisms but were available for chicks. Attempts to identify these compounds did not explain the source of excess PaA activity for the chick.

3. It is suggested that forms of PaA that are undetected by standard methods of microbiological assay differ from one food to another and require different treatments to make the vitamin available to the assay organism.
The origin of urinary aromatic compounds excreted by ruminants 2. The metabolism of phenolic cinnamic acids to benzoic acid
Authors: Martin A. K.
Published: May 2005

1. The extent to which phenolic derivatives of benzoic acid (seven); of phenylacetic acid (one); of 3-phenylpropionic acid (one) and of cinnamic acid (six) served as precursors of the urinary benzoic acid excreted by sheep was determined after administration as continuous drips via rumen or abomasal cannulas.

2. Phenolic derivatives of benzoic or of phenylacetic acid were not dehydroxylated to yield aromatic acids following administration via either route.

3. Rumen infusion of phenolic derivatives of both 3-phenylpropionic and cinnamic acids gave enhanced rumen concentrations of 3-phenylpropionic acid with negligible amounts of benzoic acid. Between 63 and 106% of the 2-, 3- or 4-hydroxy acids, of the 3,4-dihydroxy acids or of the 3-methoxy, 4-hydroxy acids infused were excreted in the urine as benzoic acid and a variable proportion, characteristic of the individual animal, of up to 20% of the dose as cinnamic acid.

4. Abomasal infusion of monohydroxy 3-phenylpropionic and cinnamic acids did not yield urinary benzoic acid increments. However, between 11 and 34% of abomasally-infused disubstituted phenolic cinnamic acids infused were excreted in the urine as benzoic acid due, it is postulated, to entero-hepatic circulation and microbial metabolism of the infused acids in the large intestine.

5. It is concluded that rumen microbial metabolism of dietary phenolic cinnamic acids to 3-phenylpropionic acid followed by its absorption and oxidation in the body tissues is responsible for the greater part of the benzoic and cinnamic acids found in ruminant urine.
A survey of human liver reserves of retinol in London
Authors: Huque T.
Published: May 2005

1. The retinol content of human liver tissue, obtained at autopsy from mortuaries in the London area, was determined in a group of 364 subjects.

2. Tissue samples from the central portion of the right lobe of the liver were saponified, extracted with light petroleum (b.p. 40–60°) and retinol assayed colorimetrically using the trifluoroacetic acid procedure.

3. The frequency distribution of retinol reserves was skewed to the right (positive skewness). The mean retinol content for the entire group was 252 mg/kg, with a median of 198 mg/kg and a range of 0–1201 mg/kg. Of the subjects, 49% had reserves in the range 100–300 mg/kg (regarded as the‘normal range’ for liver retinol) while 5% had reserves below 40 mg/kg (the arbitrary ‘cut-off’ point below which individuals are considered to be at risk). Only one subject had no detectable retinol reserves. On the other hand, 11 % of the subjects had reserves exceeding 500 mg/kg.

4. No sex-related differences were apparent, the median retinol reserves of male and female subjects being 190 and 202 mg/kg respectively.

5. Median retinol reserves varied markedly with age. They were relatively low (121 mg/kg) in infancy. but were approximately three times greater in childhood, adolescence and young adulthood. Thereafter, reserves declined gradually with increasing age to a low of 113 mg/kg in subjects over the age of 90 years.

6. When subjects were classified according to primary cause of death, the median reserves were as follows (mg/kg): accidental deaths 270, cancer 207, cardiovascular diseases 204, intestinal diseases 178, nervous diseases 164, hepatic diseases 158, respiratory diseases 141, sudden infant death syndrome 127.

7. Retinol reserves in London are substantially higher than those reported from North America and are exceeded only by those reported from New Zealand and Ghana. It is therefore concluded, from the results of this survey and also from official estimates of the dietary intake of retinol and provitamin A carotenoids, that vitamin A status in London, and probably also in the rest of Britain, is quite satisfactory.
Protein-polyphenol reactions
Authors: Hurrell R. F. , Finot P. A. , Cuq J. L.
Published: May 2005

1. Studies were made on the lysine content of casein reacted with caffeic acid oxidized aerobically under alkaline conditions or enzymically with tyrosinase (EC1.14.18.1).

2. Loss of fluorodinitrobenzene (FDNB)-reactive lysine was rapid at pH 10 and increased with time and the temperature of the reaction, with concentration of caffeic acid and with the oxygenation of the mixture. In presence of the enzyme mushroom tyrosinase, maximum reduction of reactive lysine occurred at pH 7 and was dependent on the reaction time and on the concentration of caffeic acid.

3. Reaction of α-formyl-L-[U-14C]lysine with caffeic acid at pH 10 showed the rapid formation of five reaction products which appeared to polymerize gradually as the reaction progressed.

4. The nutritionally available lysine content of the casein-caffeic acid mixtures, as assayed with rats, was reduced after both alkaline and enzymic reactions, as were faecal digestibility, net protein ratio and net protein utilization. Biological value however was not reduced.

5. In metabolic studies using goat milk casein labelled with L-[3H]lysine and reacted with caffeic acid in the same way, the lysine–caffeoquinone reaction products were not absorbed by the rat but were excreted directly in the faeces.

6. The importance of the reaction of proteins with caffeoquinone and chlorogenoquinone (formed by the oxidation of caffeic and chlorogenic acids respectively) is discussed in relation to the production of sunflower protein, leaf protein and other vegetable-protein concentrates.
Studies on vitamin D metabolism in malnourished children
Authors: Raghuramulu N. , Reddy Vinodini
Published: May 2005

1. Basal levels of serum 25-hydroxy vitamin D (25-OHD) were estimated in ten normal children and twenty-seven children with protein–energy malnutrition.

2. Five normal children and fourteen malnourished children were administered a single massive dose of 15 mg vitamin D orally and the remaining children received oral supplements of 50 μgvitamin D daily for 20 d. Blood samples were obtained after 10 and 20 d of dosing and serum 25-OHD levels were repeated.

3. The basal serum 25-OHD levels were significantly lower (P< 0·05) in malnourished children than in normal children.

4. Administration of a single massive dose of vitamin D as well as daily supplementation of small doses resulted in significant increases in serum 25-OHD levels within 10 d. However, the increase with a massive dose was of a higher magnitude. There was no significant difference between the normal and malnourished children.

5. The binding capacity of serum to 25-OHD was similar in both the groups.

6. These results suggest that vitamin D metabolism is not altered in protein–energy malnutrition.
Studies on the control of iron uptake by rabbit small intestine
Authors: Cox T. M. , O'Donnell M. W.
Published: May 2005

1. Whole-body retention in vivo and uptake of59Fe-labelled ascorbate and nitrilotriacetate chelates by intestinal slices in vitro were determined in groups of normal control rabbits and rabbits with experimentally-induced Fe deficiency.

2. Over-all absorption as measured by retention of doses of either chelate was greatly increased in conditions of Fe deficiency.

3. Intestinal Fe uptake in vitro was inhibited up to 77% in the presence of 2,4-dinitrophenol and sodium fluoride. Initial rates showed saturation within the concentration range 18–450 μmol/l, suggesting that uptake was brought about by an active transport process.

4. When studied at chelate concentrations of 450 μmol/l, significant regional differences in uptake rates were observed. Uptake in duodenal slices was increased when compared with slices from jejunum and ileum.

5. Fe uptake from ferric and ferrous chelates was greatly enhanced in Fe deficiency. This was chiefly due to increases in uptake by slices from the duodenum, but uptake into slices of distal intestine was also stimulated.

6. Kinetic analysis of Fe uptake by duodenal slices from animals rendered Fe deficient by diet or repeated bleeding indicated in both groups an increased apparent maximum velocity (Vmax) for influx of Fe without significant changes in apparent affinity for Fe.

7. The experiments provide further insight into the nature and regional distribution of transport of Fe into the intestine and suggest, in the rabbit, that important control of Fe absorption may be exerted by an active process operating at this initial entry step.
Effects of moderate increases in dietary polyunsaturated: saturated fat on plasma triglyceride and cholesterol levels in man
Authors: Kraemer Fredric B. , Greenfield Michael , Tobey Ted A. , Reaven Gerald M.
Published: May 2005

1. The effects of two isoenergetic diets differing only in the values for polyunsaturated: saturated fat (P : S values of 0·2v. 2·0) were studied in twenty adult human volunteers.

2. A period of 14 d on the high P:S diet failed to produce significant changes in fasting triglyceride levels, though there were individual variations. On the other hand, fasting cholesterol levels dropped by 10% (P< 0.005). High-density-lipoprotein-cholesterol concentrations were not influenced by changes in the P:S value.

3. Investigations into the mechanism by which changes in the P:S value might affect plasma triglyceride values revealed no consistent effects on very-low-density-lipoprotein kinetics, insulin secretion, insulin sensitivity or free fatty acid concentrations.

4. The results of this study suggest that the largest increase in dietary P:S values that is likely to be obtained on a long-term basis may have only a small effect on plasma triglyceride and cholesterol concentration.
Studies of the large intestine of sheep
Authors: Dixon R. M. , Nolan J. V.
Published: May 2005

1. Fermentation and absorption of constituents of digesta in segments of the large intestine of sheep given different diets were studied by analysis of gut contents obtained at slaughter after a period during which the sheep had been administered a non-absorbable gut marker.

2. In sheep given chopped, dried lucerne (Medicago sativa) there was net absorption of water throughout the large intestine with concomitant increases in the proportion of dry matter (DM) And organic matter (OM). There was net disappearance of 62 g OM, 1·66 g non-urea non-ammonia-nitrogen (NU–NAN) and 0·6 g(urea + NH3)-N in the caecum and proximal colon. There was no significant change in OM and NU–NAN flow through the remainder of the large intestine but there was a net disappearance of 0·3 g NH3–N. There was also net appearance of volatile fatty acids (VFA) in the caecum, most of which was apparently absorbed before the rectum.

3. Metabolism in the caecum was also studied in sheep grazing fresh pasture or consuming one of three sugar cane-bagasse-based diets, or barley pellets. In the lucerne- and pasture-fed sheep there was a net disappearance of approximately 0·5 g NH3-N/d from the caecum, while in sheep fed on bagasse plus urea, 1·4 g NH3-N/d was apparently absorbed from this region. The addition of fish meal to this latter diet resulted in apparent disappearance of 5·3 g NH3-N/d from the caecum and proximal colon.

4. There was apparent loss of NU–NAN from the caecum of sheep on all diets except the barley diet. With the latter diet there was a net gain of 1 g NU–NAN/d which was associated with relatively high VFA concentration and production; taken together these results indicate that microbial fermentation in the caecum was more extensive in the sheep fed on the barley diet than in those fed on the other diets.

5. The proportions of individual VFA in digesta from the rumen and caecum of lucerne-fed and pasture-fed sheep and in digesta from the caecum of sheep given the bagasse-based or barley diets are also reported and discussed.

6. In general the results indicate that the caecum and to a lesser extent the proximal colon were the major regions of fermentation and absorption of the components of the digesta in the large intestine.
Prediction of the suitability of soya-bean products for feeding to preruminant calves by an in-vitro immunochemical method
Authors: Sissons J. W. , Smith R. H. , Hewitt D. , Nyrup A.
Published: May 2005

1. An immunochemical test for predicting the suitability of different soya-bean products for feeding to preruminant calves was studied. Calves fitted with abomasal and re-entrant ileal cannulas, were first given a series of feeds containing heated soya-bean flour and two with casein as the protein source, and then given further test feeds in which different experimental soya-bean products, prepared under conditions which might be used commercially, provided the nitrogren source. These products (Q, R, S and T) were prepared respectively by extracting fat-free soya-bean flour with aqueous ethanol at 960, 650, 650 and 550 ml/l and at 60, 60, 78 and 78° and then treating the residue with steam for 30 min.

2. After infusion of a test feed into the abmasum measurements were made of transit time through the small intestine, flow-rate of ileal digesta, recovery of polyethylene glycol (a water-soluble marker added to the feed) and net N absorption up to the distal ileum. Glycinin and β-conglycinin, antigenic constituents of soya-bean protein, were determined in saline (9 g sodium chloride/l) extracts of soya-bean products by haemagglutination inhibition assay.

3. After calves had been given a series of four feeds containing heated soya-bean flour, they showed hypersensitivity to the flour by developing disturbances in digesta movement and N uptake. When experiments were made to compare the effects of giving feeds based on casein with those containing products R, S and T it was shown that some differences in transit times and flow-rates of digesta through, and N absorption from, the small intestine occurred. Disturbances were, however, much less than those observed with product Q feeds.

4. Haemaggultination inhibition assay of products Q, R, S and T gave titres (log2 reciprocal of highest dilution of saline extract inhibiting agglutination) of 12, 5, 3 and 2 for glycinin and 13, 3, 3 and 2 for β-conglycinin respectively. After steam treatment only product Q gave measurable titres; 10 and 11 for glycinin and β-conglycinin respectively.

5. It is concluded that the haemagglutination inhibition assay is a suitable in vitro method of indicating whether soya-bean products given in liquid feeds to preruminant calves will cause gastrointestinal allergic reactions. Furthermore, results show that the removal of deleterious factors from soya-bean meal by treating with ethanol, is critically dependent on the proportion of water present in the ethanol and the temperature of the treatment.
The uptake of nutrients from the small intestine of gnotobiotic and conventional chicks
Authors: Yokota H. , Coates Marie E.
Published: May 2005

1. Uptake of L-[2(n)-3H]methionine and 3-O-methyl[14C]-D-glucose (3MG) from jejunal loops in vivo was investigated in germ-free (GF), gnotobiotic (GN) and conventional (CV) chicks aged between 2 and 4 weeks.

2. Body-weight gain was less, and intestine weight per unit length greater, in CV and GN birds than in corresponding GF birds.

3. Uptake of both nutrients was less in CV and GN birds when calculated per g intestinal tissue, but no difference was found between any of the groups when uptake was expressed per unit length of intestine.

4. Concentration of methionine in mesenteric and cardiac blood was higher, and amounts in the intestinal wall lower, in CV chicks than in corresponding samples from GF birds.

5. Concentration of 3MG in mesenteric blood was similar in both environments but it was higher in cardiac blood and lower in the gut wall of CV birds.

6. It was concluded that uptake of methionine and glucose is not impaired by the presence of micro-organisms in the gut.
Fermentation of dietary fibre components in the rat intestinal tract
Authors: Nyman Margareta , Asp Nils-Georg
Published: May 2005

1. The fermentative breakdown of dietary fibre from various sources in the intestinal tract was studied using rat balance experiments and gas–liquid chromatrographic analysis of dietary fibre monomers in feed and faeces.

2. On a basal diet with 690 g maize starch/kg but no added fibre, small but detectableamounts of polymeric glucose, rhamnose, arabinose, xylose, galactose, mannose and uronic acids, i.e. sugars occurring in dietary fibre, were excreted in faeces.

3. Dietary fibre in wheat bran was rather resistant to fermentation; 63% was recoveredin the faeces. Guar gum, on the other hand, was almost completely fermented, whereas 19 and 25% of the uronic acids in low and high methoxylated pectin respectively, were excreted in faeces. The various constituents of sugar-beet dietary fibre (approximately equal amounts of arabinose-based hemicellulose, pectin and non-starch glucan (cellulose)) showedquite variable availability for micro-organisms in that 6–12% of the arabinose, 17–25% of the uronic acids, and 52–58% of the cellulose were recovered in the faeces.

4. Faecal nitrogen excretion increased on addition of any one of the dietary fibre preparations studied, resulting in decreased true and apparent protein digestibility values.

5. The faecal dry weight increment was most pronounced when feeding bran and could then almost be accounted for by the remaining fibre and by protein. The less-prominent bulking effect ot guar gum and pectins, that were much more extensively fermented, could be only partly explained by dietary fibre and protein.
Trace nutrients 4. Iodine in British food
Authors: Wenlock R. W. , Buss D. H. , Moxon R. E. , Bunton N. G.
Published: May 2005

1. The amounts of iodine in nationally representative samples of prepared and cooked groups of foods and in a wide variety of individual foods and food products were determined colorimetrically. The amounts of erythrosine, a red food colour containing 577 mg I/g were also determined in selected foods and diets by high-performance liquid chromalography.

2. The average British diet was calculated to provide 323 μgI/d but only 255 μg if two fruit samples containing large amounts of glacé cherries were discounted. Of the total, 92 μg was derived from liquid milk. Meat and meat products provided 36 μgand cereal products 31 μg, but fresh fruitsand sugars, vegetables and beverages provided little I. Fish and fish products, though rich in I, contributed only 5% to the total intake.

3. Milk was the most variable as well as the most important individual source of I. Summer milk samples contained 70 μg/kg and winter milk 370 μkg on average. Milk products, including butter and cheese, and eggs were also rich in I.

4. Some processed foods contained erythrosine, particularly glacé cherries and some pink or red confectionery items, biscuits, cherry cake, canned strawberries and luncheon meat. However, none of these are major foods in the average household diet and erythrosine would therefore contribute little more than 10 μg I/d to most diets.

5. The average daily intake of I was lower than in similar studies in the USA, but wastwice the provisional UK recommended intake. This study provides no evidence that I intakes in the UK could be too low or loo high for health.
Early life undernutrition in rats
Authors: Smart J. L. , Bedi K. S.
Published: May 2005

1. A detailed investigation was made of the motor performance of rats which had impaired cerebellar and muscular growth resulting from early-life undernutrition.

2. Developing rats were growth-retarded by underfeeding their mothers during pregnancy and lactation. They were fed ad lib. from 25 d of age.

3. Adult male previously-undernourished (PU) and well-fed control rats were given tests of motor behaviour commencing at 5 months of age. They were required to run backwards to maintain their position on a revolving drum. Aspects of the test situation were varied systematically: visual environment, interval between trials, test duration and drum speed.

4. PU rats had a 29% body-weight deficit compared with controls at 5 months.

5. There was no evidence of impaired motor performance by the PU rats under any of the test conditions.
Lymphocyte proliferation kinetics in malnourished children measured by differential chromatid staining
Authors: Murthy P. Balakrishna , Rahiman M. Abdul , Tulpule P. G.
Published: May 2005

1. Utilizing the bromodeoxyuridine differential-chromatid labelling technique the in vitro proliferation of lymphocytes from children with kwashiorkor was followed in phytohaemagglutinin-stimulated cultures and compared with controls.

2. Analyses of first, second and third or subsequent division cells as a function of culture time between 40 and 96 h showed that cell-cycle duration was prolonged in kwashiorkor cultures. The extent of this increase was approximately 4.5 h for the first-division cells and 1.5 h for third-division cells.

3. The peak for second-division cells was depressed in kwashiorkor cultures.

4. A decreased number of third or subsequent-division cells was observed in kwashiorkor cultures at all time points studied.

5. These findings suggest that the loss in lymphocyte activity to PHA in malnourished children in general could be due to an increase in cell-cycle duration of responding lymphocytes.
Physiological effects of fibre-rich types of bread
Authors: Van Dokkum W. , Wesstra Anneke , Schippers Francien A.
Published: May 2005

1. Twelve young adult male volunteers were given a low-fibre white bread diet (9 g neutral-detergent fibre (NDF)/d) and a medium-fibre coarse-bran bread diet (22 g NDF/d), each lasting 20 d. In a third period of 20 d the volunteers were subdivided in groups of four, consuming a high-fibre coarse-bran bread diet (35 g NDF/d). a medium-fibre fine-bran bread diet (22 g NDF/d, bran particle size < 0.35 mm) or a wholemeal bread diet (22 g NDF/d), Retention of calcium, magnesium, iron, zinc and copper were determined during each 20 d period.

2. An increase of the amount of dietary fibre (through bran in bread) from 9 g to 22 g NDF/d resulted in a significantly increased mineral intake, but also faecal excretion increased significantly; mineral retention remained almost constant.

3. Both intake and faecal excretion of all minerals studied, except faecal Ca. increased further (P < 0.05) on the diet providing 35 g NDF/d: only Fe balance decreased significantly. No significant differences with respect to intake, excretion (except urinary Ca) and balance of the minerals could be detected between the coarse-bran bread and fine-bran bread diets providing 22 g NDF/d. Faecal Fe, Cu balance and Mg balance increased significantly during the wholemeal bread period compared to the coarse-bran bread diet providing 22 g NDF.

4. Serum cholesterol increased significantly, i.e. by 0.3 mmol/1, during the coarse-bran bread diet providing 22 g NDF, compared to the white-bread diet.

5. It is concluded that increasing the amount of bran in bread does not appear to affect mineral balance considerably but there seems to be an influence on mineral availability. The increased intake was accompanied by increased faecal excretion.
Changes in lens proteins in undernourished and well-nourished patients with cataract
Authors: Seetharam Bhat K.
Published: May 2005

1. Patients with cataract were classified into undernourished (twenty-eight subjects) and well-nourished (twenty-seven subjects) groups based on the anthropomtric index, weight (kg)/height (m)2. Those with a value for the index of less than 18 were considered as undernourished.

2. Lenses were classified into four groups on the basis of nuclear colour as proposed by Pirie (1968). Lenses of pale uniform colour or yellow colour were included in group 1, those with brownish-yellow nucleus in group 2, those with a yellowish-brown nucleus in group 3 and those with brown nucleus in group 4.

3. Irrespective of group, the wet weight, dry weight, percentage moisture and total protein content of cataractous lenses from undernourished patients were similar, as were the corresponding values for well-nourished patients. On the other hand, the percentage of soluble proteins in lenses tended to decrease with deepening of nuclear colour in both groups of patients. Further, soluble protein concentrations in lenses from undernourished patients were significantly lower as compared to those from well-nourished patients.

4. The results suggest that nutritional factors could influence the composition of cataractous lenses.
Foetal mortality in moderately zinc-deficient rats is strictly related to the process of parturition: effect of maternal essential fatty acid supplementation
Authors: Cunnane S. C.
Published: May 2005

1. Although disrupted parturition and high foetal losses have previously been reported in pregnant rats maintained on zinc-deficient diets this is the first report to differentiate between the effects of reduced Zn intake and the effects of reduced food intake on theoutcome of pregnancy in the rat.

2. Rats maintained on a 0·5 mg Zn/kg diet for the last 7 d of gestation or on a 5 mg Zn/kg diet throughout gestation did not consume significantly less food than rats given 10 or 20 mg Zn/kg diets except during the last 2 d of gestation. Pair-feeding of Zn-adequate rats (20 mg/kg) to those given low-Zn diets for the last 2 d of gestation did not affect the outcome of pregnancy in these rats.

3. In the rats maintained throughout gestation on 5 mg Zn/kg or on 0·5 mg Zn/kg in the last 7 d of gestation, parturition onset and duration were not significantly altered. Foetal rvival was very significantly reduced but only from day 22 onwards; before the onset of parturition, foetal survival was not significantly affected by Zn deficiency during gestation.

4. Subcutaneous injection of evening primrose (Oenothera biennis) oil into rats throughout gestation enhanced foetal and neonatal survival in rats given 5 mg Zn/kg but reduced foetal survival in rats given 0·5 mg Zn/kg in the last 7 d of gestation.

5. The results suggest three points: (1) subtotal Zn deficiency during gestation in the rat jeopardises foetal survival at parturition without affecting the onset or duration of parturition, (2) foetal death in rats maintained on Zn-deficient diets occurs only in relation to parturition itself, (3) provided that Zn intake near term is at least 5 mg/kg, supplemental essential fatty acids (evening primrose oil) will reduce foetal mortality during parturition and in the neonatal period.
Effects of cold exposure on feed protein degradation, microbial protein synthesis and transfer of plasma urea to the rumen of sheep
Authors: Kennedy P. M. , Christopherson R. J. , Milligan L. P.
Published: May 2005

1. Three diets of barley–canula-seed (Brassica campestiris), lucerne (Medicago sativa) or chopped brome-grass (Bromus inermis) were given at intervals of 3 h to closely-shorn Suffolk wethers held at a temperature of 1–5° (cold) or 22–24° (warm). Apparent digestibility of organic matter (OM) and nitrogen was reduced by 0·08–0·05 and 0·04 units respectively for lucerne and brome-grass diets given to cold-exposed sheep, but no treatment effects on digestibility were observed for the barley–CSM diet. Measurements achieved using infusion of the digesta markers 58Co-EDTA and 103Ru-phenanthroline (103Ru-P) showed that cold exposure depressed apparent OM digestion in the stomach and intestines by 33 and 42 g/d for the lucerne diet, and 13 and 35 g/d for the brome-grass diet respectively.

2. The turnover time (h) of the l03Ru-P marker in the rumen of warm sheep was 38·9 for barley–CSM, 18·4 for lucerne, and 15·6 for brome-grass. In cold-exposed sheep, 103Ru-P turnover time (h) tended to be reduced to 32·3, 12·3 and 15·3 for the three diets, respectively. OM fermentation in the stomach was highly related to 103Ru-P turnover time for lucerne and brome-grass diets.

3. Cold exposure increased the escape of dietary N from the abomasum by 0·04 and 0·09 of dietary N intake for sheep given lucerne and brome-grass diets respectively. Dietary N degradation was closely related to 103Ru-P turnover time for lucerne, and to the proportion of large particles in rumen digesta for the brome-grass diet. Estimates of feed N degradation made by use of information on the rate of fermentation of the diet in nylon bags and 103Ru-P turnover time were consistently lower than those observed in vivo for barley–CSM and lucerne diets. Intestinal digestibility of non-ammonia N was not significantly changed by cold exposure.

4. Transfer of urea from plasma to the rumen was 1·4–2·5 g N/d for the barley–CSM and lucerne diets, but the value for brome-grass was 4·5–4·9 g N/d. Cold exposure did not affect urea transfer. The production of ammonia from feed and endogenous protein was approximately 0·66 and 0·47 g N/g N intake of barley–CSM and lucerne diets, with no effect of cold exposure. Cold exposure reduced the value from 0·57 to 0·38 for brome-grass.

5. The results are compared with those obtained previously with pelleted hay, and the importance of large particle breakdown in the prediction of OM and N fermentation using nylon bags is discussed.
Short-lived radionuclides in nutritional physiology. A model study with l-[Me-11C]methionine in the pig
Authors: Stålnacke C.-G. , Jones B. , Långström B. , Lundqvist H. , Malmborg P. , Sjöberg S. , Larsson B.
Published: May 2005

1. A‘new’carbon radioisotope, 11C, for use in nutritional studies is presented. It has a 20 min half-life, and decays by positron emission giving annihilation photons of 511 keV energy (Wolf & Redvanly. 1977). Thus repeated studies can be made with short time intervals and the distribution of radioactivity in the experimental animal can be detected externally.

2. 11C was produced with a tandem Van de Graaff accelerator and L-[Me-11C]methionine was synthesized and used in model experiments in the pig. The tracer wasadministered intravenously through a catheter in the jugular vein of pigs weighing between 40 and 100 kg. In a series of experiments, one pig received a low-melhionine diet supplemented with DL-methionine to give three different levels of methioninc intake.

3. The radioactivity distribution between liver and muscle was measured as a function of time by external detectors for 2–3 h after administration. Blood and exhaled CO2 were sampled and measured for radioactivity.

4. The results indicate that 11C is a useful radionuclide in nutritional studies in intact large domestic animals.
Effect of dietary protein level, and an anabolic steroid, ethylestrenol, on the growth, food conversion efficiency and protein efficiency ratio of rainbow trout (Salmo gairdneri)
Authors: Ince B. W. , Lone K. P. , Matty A. J.
Published: May 2005

1. Three isoenergetic test diets containing 320, 430 and 530 g protein/kg, with (experimental) and without (control) inclusion of an anabolic steroid, ethylestrenol, were given to rainbow trout (Salmo gairdneri) of mean initial weight 27 g, for 60 d.

2. After 60 d, all trout groups were given an identical, steroid-free, commercial diet (410 g protein/kg) for a further 30 d, to observe withdrawal effects on growth.

3. The weight and length of trout given the 430 and 530 g protein/kg control diets were significantly greater after 60 d than those given the 320 g protein/kg control diet.

4. Inclusion of steroid enhanced the weight and length of trout given the 320 and 430 g protein/kg experimental diets, exerting a preferential effect on weight as opposed to length.

5. After steroid withdrawal, a significant difference between the weight and length of the 320 g protein/kg control and experimental groups was still apparent.

6. An increase in dietary protein increased the food conversion efficiency, and decreased the protein efficiency ratio. Inclusion of steroid increased both these factors over the respective controls.

7. Protein assimilation decreased, and faecal nitrogen content increased with increasing dietary protein. In trout given steroid, protein assimilation and apparent digestibility was higher, and facecal N content, lower than the controls.

8. Muscle protein increased with increasing dietary protein, and was higher in trout given steroid.

9. Relative liver weight increased with increasing dietary protein. Inclusion of steroid resulted in a reduction in relative liver and gut weight, and an increase in kidney weight.

10. It is concluded that ethylestrenol promotes both the growth and efficiency of nutrient utilization of trout. The magnitude and duration of these effects are a function of the dietary protein level.
Redistribution of vitamin A in tissues of rats with imposed chronic confinement stress
Authors: Nakano Kiwao , Morita Akihito
Published: May 2005

1. The effect of confinement stress on the metabolism of vitamin A was studied in ratsby following changes in tissue distribution of the vitamin for 29 d. In order to minimizepredicted errors which might result from fluctuation of vitamin A intake, the effect of the stress was investigated in rats fed on a vitamin A-free diet.

2. Daily stress for 6 h induced an enlargement of the adrenals with a concomitant involution of the thymus and spleen, values returning to normal within 11–15 d.

3. The stress caused an immediate decrease in the content of vitamin A in serum.

4. Feeding rats a vitamin A-free diet resulted in a significant increase in the vitamin Acontent of the kidney. Imposing stress on these rats inhibited markedly the increase in kidney vitamin A content.

5. The stress produced no appreciable change in levels of the vitamin in the liver andtestes.

6. There was a preferential accumulation of the vitamin in the adrenals of the stress-imposed rats even though they were fed on a vitamin A-free diet.

7. In conclusion, the results of the present study demonstrated that chronic immobilization stress produced marked tissue-dependent changes in their vitamin A content.
Body fatness, relative weight and frame size in young adults
Authors: Baecke Jos A. H. , Burema Jan , Deurenberg Paul
Published: May 2005

1. Body-weight, body height, knee width, wrist width and skinfold measurements were made on males (n 139) and females (n 167) in three age-groups (20–22, 25–27 and 30–32 years). Percentage of body fal was calculated from skinfold thicknesses using regression equations according to Durnin & Womersley (1974), Three indices of relative weight were calculated: W/H2, W/Hp and W/Ŵ, where W is body-weight, H is body height, p is the exponent that made the index of relative weight independent of height and W is the weight, estimated from body height and frame size.

2. The standard error of the estimate of body-weight was only reduced by 5% in males and by 13% in females when, in addition to body height, knee width was taken into account.The addition of wrist width did not improve the accuracy of estimation of body-weight in either sex. Therefore in further analyses W was estimated from body height and knee width. In the present population the exponent p was 1·7 in males and 1·6 in females.

3. The correlations between the percentage of body fat and the indices, W/H2, W/HP, and W/Ŵ, were all very similar, being approximately 0·8 in both sexes.

4. A positive relationship was observed between percentage of body fat and knee width in females, which may be explained by an artifact of measurement.

5. In conclusion it can be stated that the accuracy of estimation of percentage of body fat was not improved when the index of relative weight was adjusted for knee width or wrist width in the present population. The W/H2was the most preferable of the three indices which were calculated.
The effect of early postnatal undernutrition on the growth and development of the rat brain
Authors: Morgan B. L. G. , Naismith D. J.
Published: May 2005

1. Rat pups were undernourished during the period of the brain growth-spurt by feeding their mothers a low-protein diet from the third day post partum.

2. The pups were killed on days 5,6,9,12,16,20 and 24 post partum, and their brains were analysed for protein, DNA, glycosides and glycoproteins. The activities of four enzymes involved in neurotransmission, and in the synthesis of glycolipids and myelin were also measured. Results of the analyses were compared with those obtained for pups that were suckled by well-nourished dams.

3. The brains of the undernourished pups contained substantially less protein and DNA; gangliosides and glycoproteins were also reduced.

4. All four enzymes showed lower peak activities in the nutritionally deprived animals, and the attainment of peak activity was retarded by several days.

5. These results suggest that undernutrition imposed during the brain growth-spurt leads to a deficit in the glial cell population and thus in the capacity to form myelin, and reduced deveiopment of cellular processes.
The effect of protein-deficient isoenergetic diets on the growth of rat jejunal mucosa
Authors: Syme Gabrielle
Published: May 2005

1. Newly weaned 21-d-old male rats were given isoenergetic diets containing 200, 100 and 50 g protein/kg for 7, 14, 28 or 70 d. The mid-jejunum was removed from the rats and a micrometric analysis of the mucosa was made. The following measurements were made: number of villi/mm2, vilius dimensions, villus surface area, crypt depth, crypt: villus, the number of cells/crypt in metaphase arrest per h.

2. Comparisons were made between animals of the same age but on different diets, and animals on the same diet but of different ages. The latter comparison gave information on the effect of protein deficiency on the pattern of maturation of each feature of The villus or crypt studied.

3. The effect of protein deficiency was not consistent at each stage of maturation. For instance villus height was decreased when compared with the controls following 28 d on a protein-deficient diet but not after 7 or 70 d.

4. The only measurement to be unaffected by protein deficiency was the number of villi per unit area.

5. In general the 50 g protein/kg diet had a more pronounced effect than the 100 g protein/kg diet. Protein deficiency delayed maturation by either slowing or inhibiting changes seen in normal maturation.

6. In rats given 50 g protein/kg diet, although the villus surface area did not increase as the rats matured there were increases in epithelial cell production rate and number of crypts per villus.
The effect of protein supplementation on digestion and glucose metabolism in young cattle fed on silage
Authors: Gill Margaret , Beever D. E.
Published: May 2005

1. Ryegrass (Lolium multiflorumcv. RvP) silage was given to twelve Friesian steer calves (initial live weight (LW) 106 kg) at 2·3 kg dry matter (DM)/calf per d, alone, or with a supplement of fish meal at 50(FM1) or 100(FM2) g/kg silage DM per d.

2. The rate of flow of nutrients into the duodenum was measured using a dual-marker technique. Glucose irreversible-loss rates and the contribution of propionate to gluconeogenesis were measured using continuous infusions of [U-14C]glucose and [2-14C]propionate.

3. Amino acid flow into the duodenum was significantly (P< 0·01) increased from 238 g/d on the control treatment to 319 g/d on FM2, but there was no response to FM1 (P> 0·05).

4. Glucose irreversible loss rate remained constant with an average value of 1·86 mg/min per kg LW.

5. Neither the percentage of glucose synthesized from propionate (average 30) nor the percentage of propionate converted to glucose (average 45) was significantly altered by treatment (P> 0·05).
Foetal and maternal rates of urea production and disposal in well-nourished and undernourished sheep
Authors: Hodgson J. C. , Mellor D. J. , Field A. C.
Published: May 2005

1. Five monotocous and twoditocous Scottish Blackface ewes with indwelling catheters in an umbilical artery and vein of one foetus only and in both maternal jugular veins were used.

2. Experiments were conducted over a period of 2 d when [I4C]urea was infused intravenously over 9 h into either the mother or foetus, separate days being used for each infusion. Two series of experiments were completed, one in well-nourished and the other in undernourished sheep at 125–141) and 138–143 d of gestation respectively.

3. Plasma urea specific radioactivities of the mother and infused foetus at plateau were used to determine the urea flux-rates within and between mother and foetus. The mean rate of foetal urea production (Ffo) was 1.45 and 1.63 mg/min per kg foetus in well-nourished and undernourished ewes respectively. The corresponding rates of maternal urea production (Fmo) were 0.49 and 0.37 mg/min per kg live weight respectively and there was a close correlation between the rate of maternal urea disposal (Fom) and the dietary nitrogen intake.

4. The values ofFfowere used to calculate the maximum potential for foetal gluconeogenesis from deaminated amino acids. These calculations were compared with published information on the over-all rates of foetal gluconeo genesis in well-nourished ewes.

5. The foetal entry rate of urea expressed on a body-weight basis was high, approximately 8.5 times that of the mother, but it was a threefold overestimate ofFfo. The maternal entry rate was 1.3 timesFmoand the significance of this in relation to assessing differences in urea entry rates in pregnant and non-pregnant sheep is discussed.
The effects of cold exposure of pregnant sheep on foetal plasma nutrients, hormones and birth weight
Authors: Thompson G. E. , Bassett J. M. , Samson Debbie E. , Slee J.
Published: May 2005

1. Five pregnant sheep, with indwelling catheters positioned for withdrawal of maternal right-atrial and foetal arterial blood, were exposed for 2 h to neutral and to cold (– 1° and wool-clipped) environmental temperatures. Acute maternal cold exposure increased the concentrations of glucose, glycerol and non-esterified fatty acids in maternal plasma and increased the concentration of glucose in foetal plasma, but not glycerol or non-esterified fatty acids. The concentration of corticosteroids in maternal piasma increased. The concent ration of corticosteroids in foetal plasma did not change but the concentration of insulin increased.

2. Thirteen pregnant sheep were housed at thermoneutrality and thirteen similar, sheep fed the same amount of food, were clipped and exposed to cold during the last 5– 6 weeks of pregnancy. Chronic maternal cold exposure increased the birth weight of both single and twin lambs.

3. It is concluded that exposure of pregnant sheep to cold can alter the partition of some nutrients between mother and foetus in favour of the foetus, and it is suggested how this may be brought about.