bluuebunny/crossref_metadata_2025 huggingface dataset:
The nutritive value of silages Digestion of organic matter, gross energy and carbohydrate constituents in the rumen and intestines of sheep receiving diets of grass silage or grass silage and barley
Authors: Thomas P. C. , Kelly N. C. , Chamberlain D. G. , Wait M. K.
Published: June 2005

Two experiments were conducted to study the digestion of organic matter, gross energy and carbohydrate constituents in the rumen, small intestine and caecum and colon of sheep given grass silage diets. Three silages made from perennial ryegrass (Lolium perenne) with formic acid as an additive were used. One was made from first-harvest grass in the spring and the others from regrowth grass cut from a single sward in either early autumn or late autumn. Expt I involved a comparison between the spring silage given alone or supplemented with barley (silage:barley, 4:I dry matter (DM) basis). Expt 2 involved a comparison between the early-cut and late-cut autumn silages.

In Expt I, supplementation of the silage with barley resulted in a non-significant (P > 0.05) reduction in the proportion of digestible energy (DE) and digestible organic matter digested in the rumen and an increase in the proportions digested in the small intestine. There were also pronounced effects of barley on ruminal cellulolysis and the proportion of digestible cellulose broken down in the rumen was reduced (P < 0.05) from 0.90 to 0.77. There was an increased passage of α-linked glucose polymers to the duodenum but even with the supplemented diet 0.91 of the dietary polymers were digested in the rumen. The molar proportion of propionic acid in the rumen tended to be reduced and there were increases in the proportions of butyric acid (P < 0.01) and acetic acid.

In Expt 2, the digestibility of organic matter, gross energy and cellulose in the early-cut silage was higher (P < 0.01) than in the late-cut silage but there were no significant (P < 0.05) differences between silages in the sites of digestion of these constituents. However, the molar proportion of acetic acid in the rumen was higher (P < 0.01) and the molar proportion of propionic acid was lower (P < 0.01) with the late-cut silage than with the early-cut silage.

The results are discussed in relation to the voluntary intake and utilization of high-digestibility silages.
Whole body and tissue protein synthesis in cattle
Authors: Lobley G. E. , Milne Vivien , Lovie Joan M. , Reeds P. J. , Pennie K.
Published: June 2005

The daily rates of synthesis of protein by the whole body and by the individual tissues were determined in two Hereford × Friesian heifers (236 kg and 263 kg live weight), and a dry Friesian cow (628 kg live weight).

The rate of whole-body protein synthesis (g protein/d) was estimated from the total flux through the blood of [3H]leucine and [3H]tyrosine following infusion at a constant rate for 8 h.

The fractional rates of protein synthesis (ks) in the tissues (g synthesized/d per g tissue protein) were obtained after slaughter of the animals at the end of the infusion period. The fractional rate of protein synthesis was calculated assuming that the specific radioactivity of free tyrosine in either the blood (to giveks, b) or the tissue homogenate (to giveks, h) defined closely the specific radioactivity of the amino acid precursor for protein synthesis. Total protein synthesis (As, borAs, h; g/d) in an individual tissue was calculated as the product ofks, b) (orks, h) × protein content.

Based on the total leucine flux, i.e. without correction for oxidation, 1.6 kg protein were synthesized daily in the heifers; for the cow this value was 2.0 kg/d.

The sum of the daily total synthesis in the major tissues (muscle+bone+brain, gastrointestinal tract (GIT), liver, hide) gave values of 1.4–1.9 kg/d based onAs, b, and 2.2–3.0 kg/d based onAs, h.

The percentage contributions of the individual tissues to the total protein synthesis were similar in all three animals, for example based onAs, hmuscle was 12–16; carcass (muscle+bone+brain) 32–33; GIT 38–46; liver 7–8; skin 14–21%.

The contribution of muscle to total synthesis estimated from the leucine flux was 19–22%; this value is in agreement with those calculated on the same basis for other species.

The energy cost of protein synthesis was estimated to account for a maximum of 30% of heat production.
The fate of99Mo-labelled sodium tetrathiomolybdate after duodenal administration in sheep: the effect on caeruloplasmin (EC1.16.3.1) diamine oxidase activity and plasma copper
Authors: Mason J. , Lamand M. , Kelleher C. A.
Published: June 2005

1. The effect of acute duodenal infusion of99Mo-labelled sodium tetrathiomolybdate on caeruloplasmin (ferroxidase;EC1.16.3.1) was examined in sheep. The diamine oxidase activity of this enzyme with respect to two substrates,p-phenylenediamine ando-dianisidine (both at their apparentKmconcentrations) was inhibited.

2. The99Mo appeared rapidly in plasma and was at first present predominantly in a trichloroacetic acid insoluble form; inhibition of oxidase activity was related to the levels of TCA-insoluble Mo. The behaviour of the copper prosthetic groups of caeruloplasmin was altered since some plasma Cu precipitated with the protein fraction after TCA treatment. The appearance of TCA insoluble Cu was related to the level of TCA-insoluble99Mo and corresponded to the inhibition of diamine oxidase activity.
Dependence of thyroxine utilization rate on dietary composition
Authors: Ingram D. L. , Evans S. E.
Published: June 2005

1. The rate of utilization (k) of labelled thyroxine increased when energy intake, given as standard pig meal, was doubled from 20 to 40 g/kg body-weight per d. When the bulk of food was increased, but not its energy content, the value of k did not change. Ambient temperature was constant throughout the experiment.

2. Groups of pigs were given pig meal at 20 g/kg body-weight, 40 g/kg body-weight or 20 g/kg body-weight plus a supplement. The supplement was of equivalent energy content to 20 g pig meal/kg body-weight and consisted of coconut (high-fat), fish meal (high-protein) or glucose. The values of k were similar on diets (g/kg body-weight) of 40 pig meal, 20 pig meal plus coconut, and 20 pig meal plus fish meal. When the supplement was glucose however the values of k were similar to that for 20 g pig meal/kg body-weight.

The plasma concentrations of T4, and triiodothyronine were not affected by eating a meal, or by changing the energy intake presented as pig meal. A comparison between pigs given 20 g pig meal/kg body-weight plus supplements of bran, coconut, fish meal or glucose revealed differences in the concentration of both hormones. When food was withdrawn for 5 d the concentrations of both hormones declined.
The response of serum 25-hydroxyvitamin D concentrations to vitamin D intake and insolation in sheep
Authors: Smith B. S. W. , Wright H.
Published: June 2005

1. Vitamin D-depleted, housed sheep were given diets providing fixed intakes of cholecalciferol ranging from 0.0 to 0.8 μg/kg body-wt per d for 220 d. Thereafter they were shorn, deprived of dietary cholecalciferol and turned out from 30 June to 30 November. The concentration of 25-hydroxyvitamin D (25-OHD) in serum was determined at frequent intervals.

2. The serum concentrations of 25-OHD took approximately 10 weeks to stabilize after which they reflected dietary intake over the range 0.1–0.4 μg/kg body-wt per d. For intakes of 0.4 and 0.8 μg/kg body-wt per d the mean maximum concentrations were similar, but the rates of increase differed. The latter was proportional to the logarithm of intake over the range studied.

3. Changes in serum 25-OHD due to insolation were similar in all sheep regardless of their starting values, and consequently in some animals reached levels considerably greater than from the dietary source.

4. Although the response of serum 25-OHD to the higher dietary intakes appeared to be limited there was no evidence of any such control over the response to endogenously-synthesized vitamin.
Biotin status, blood pyruvate carboxylase (EC6.4.1.1) activity and performance in broilers under different conditions of bird husbandry and diet processing
Authors: Whitehead C. C. , Bannister D. W.
Published: June 2005

1. Three experiments were conducted to investigate the relationships between blood pyruvate carboxylase (pyruvate: carbon dioxide ligase (ADP-forming),EC6.4.1.1; PC) activity, growth performance and dietary biotin level in broilers under different husbandry conditions. Blood PC activity was also used to gain information on the ingestion of biotin of faecal origin by birds housed on wood shavings and the effect of steam-pelleting on the biotin content of diets.

2. Blood PC activity and relationship to dietary biotin level were similar in birds kept under different husbandry conditions.

3. Biotin requirement for growth was higher in birds kept under conditions that allowed them to reach their growth potential more fully.

4. The contribution of biotin of faecal origin to the biotin intake of birds housed on wood shavings was negligible at 3 weeks of age but by 7 weeks was equivalent to approximately 0.01 mg/kg diet.

5. Steam-pelleting did not affect the stability or availability of biotin of natural or synthetic origin in diets.

6. It is concluded that blood PC activity is a good criterion of biotin status and requirement in fast-growing
The effect of zinc deficiency on alkaline phosphatase (EC3.1.3.1) and its isoenzymes
Authors: Adeniyi F. A. , Heaton F. W.
Published: June 2005

1. Zinc deficiency in young rats reduced both the total alkaline phosphatase (EC3.1.3.1) activity and Zn concentration in serum, kidney, small intestine and femur.

2. Addition of 0.01 mM-exogenous Zn had no greater activating effect with extracts of kidney, small intestine and femur from Zn-deficient than control rats, indicating that the main effect of the deficiency was on the amount of enzyme present rather than the efficiency of its operation. Exogenous Zn increased the activity of enzyme in serum of Zn-deficient rats, but it was still lower than in the serum of control animals.

3. Electrophoresis on polyacrylamide gel separated the alkaline phosphatase activity from all tissues into two bands. The bands had similar electrophoretic mobilities and appeared to be qualitatively identical in corresponding tissues from Zn-deficient and control rats.

4. Zn deficiency eliminated the first band found in serum from control rats and it had selective effects on the activity of individual bands in other tissues. The major inhibitory effect was on the first bands of enzyme activity in kidney and femur, but in small intestine only the second band was affected. In liver the activity of the first band was increased and that of the second band decreased by similar amounts.
Regulation of hepatic lipogenesis by dietary maize oil or tripalmitin in the meal-fed mouse
Authors: Herzberg G. R. , Janmohamed N.
Published: June 2005

The effect of varying dietary levels of maize oil and tripalmitin (0–250 g fat/kg) on hepatic lipogenesis and the levels of hepatic fatty acid synthetase (FAS), glucose-6-phosphate dehydrogenase (EC1.1.1.49; G6PD), malic enzyme (EC1.1.1.38, 1.1.1.39, 1.1.1.40; ME) and glucokinase (EC2.7.1.2; GK) was examined in meal-fed mice.

2. Meal-fed mice compared to mice fedad lib.show enhanced hepatic lipogenesis as demonstrated by an increased rate of in vivo fatty acid synthesis and increased levels of FAS, ME and G6PD. The level of GK in meal-fed mice was unchanged by meal feeding.

3. Maize oil more effectively reduced in vivo hepatic lipogenesis than tripalmitin in meal-fed mice.

4. Maize oil more effectively reduced the hepatic levels of FAS, G6PD, ME and GK than tripalmitin in meal-fed mice.

5. The increased inhibition by maize oil is observed at all levels of fat in the diet investigated and has been shown not to be due to decreased carbohydrate intake nor to differences between the absorption of maize oil and tripalmitin.
The effect of meal frequency and protein concentration on the composition of the weight lost by obese subjects
Authors: Garrow J. S. , Durrant Merril , Blaza Sandra , Wilkins Deborah , Royston P. , Sunkin Shirley
Published: June 2005

1. Nitrogen balance, weight loss and resting metabolic rate were measured in thirty-eight obese inpatients on 3.4 MJ (800 kcal)/d diets over 3 weeks.

2. All subjects were fed on 13% protein-energy in three rneals/d for the first week.

3. In weeks 2 or 3, using a cross-over design, ten subjects were fed on 15 or 10% protein-energy as three meals/d; fourteen subjects were fed on five or one meal/d with 13%protein energy; and fourteen subjects were fed on 15% protein-energy as five meals/d or 10% protein-energy as one meal/d.

4. N loss was least on the high-protein week and frequent-meal week: the largest difference was found when these effects were combined (P< 0.001).

5. When protein-energy was held constant at 13% N loss decreased significantly (P< 0.01) between week 2 and 3, but when the protein-energy was manipulated there was no significant N conservation in the third week. This suggests that the protein:energy value is more important than meal frequency in the preservation of lean tissue.

6. Weight loss was also least on the ‘high-protein’ week and ‘frequent-meal’ week, but this result reached significance only when the effects were combined (P< 0.05).

7. Resting metabolic rate decreased with time but was not significantly altered by the dietary regimens.

8. Therefore, during the first 3 weeks at an intake of 3.4 MJ/d, a diet with a high-protein concentration, fed as frequent small meals, is associated with better preservation of lean tissue than an isoenergetic diet with lower-protein concentration fed as fewer meals. There was no evidence that meal frequency or protein concentration affect the rate of fat loss.
The role of cereals in the aetiology of nutritional rickets: the lesson of the Irish National Nutrition Survey 1943–8
Authors: Robertson Iris , Ford J. A. , McIntosh W. B. , Dunnigan M. G.
Published: June 2005

1. Review of the evidence of the Irish Nutrition Survey concerning a marked rise in the incidence of rickets in Dublin in 1942 concludes that a rise in the extraction rate of the national flour from 70 to 100% was principally responsible.

2. This rise and subsequent decrease in incidence as the extraction rate of flour was reduced is not explained by changes in the proportion of children protected by vitamin D supplements or by small changes in dietary vitamin D intake.

3. The evidence suggests that nutritional rickets in man cannot be explained on the basis of deficient vitamin D intake alone, whether derived from diet or U.V. radiation.
The diet of individuals: a study of a randomly-chosen cross section of British adults in a Cambridgeshire village
Authors: Bingham Sheila , McNeil N. I. , Cummings J. H.
Published: June 2005

1. The dietary intakes of sixty-three adults, randomly-selected from the electoral role of a large village near Cambridge, have been measured using the weighed-intake technique for 7 d.

2. Mean (±sD) daily intakes (g) for men and women respectively were: energy (MJ) 10.0±2.4, 8.2±2.1; fat 104±27,90±21; protein 77±20,67± 16; carbohydrate 285±81,229±74; sucrose 91±47, 57±33.

3. When interviewed at the end of the study 40% of subjects said they were watching their weight.

4. Women ate less food over all than men, and proportionately less potato and bread, and used only one-third as much sugar in drinks, probably in an attempt to control their weight. Men took considerably more alcohol than the women. In the age-group 20–39 years alcohol provided 9% (1.0 MJ/d) of the total energy intake in the men.

5. Wide variation in the intake of nutrients was observed amongst the individuals. For vitamin C and fibre intake this was partly explained by seasonal variation but for most nutrients total energy intake and food choice were the main determinants. The range. of intakes of nutrients such as fat was similar in these individuals to that seen amongst countries internationally. It is suggested that if differences in nutrient intake amongst the various populations of the world can be associated with disease risk, then the same interpretation should be possible in individuals.
A biochemical evaluation of the erythrocyte glutathione reductase (EC 1.6.4.2) test for riboflavin status
Authors: Prentice A. M. , Bates C. J.
Published: June 2005

1. Chronic marginal riboflavin deficiency was induced in groups of weanling rats by feeding a deficient diet supplemented with 0, 0·5, 1·0 and 1·5 mg riboflavin/kg diet. Ad lib.- and pair-fed controls received 3·0 and 15 mg riboflavin/kg diet respectively.

2. Serial measurement of erythrocyte NAD(P)H2 glutathione oxidoreductase (glutathione reductase; EC 1.6.4.2) and its activation coefficient revealed that after 12 weeks a steady-state of deficiency had been reached following initial fluctuations in status; the animals were then killed, and their tissues analysed.

3. Food intake, growth rate and the appearance of pathological signs were directly proportional to riboflavin content; however relative liver weight was increased above control levels only in the most-severelydeficient group, and anaemia was not detected in any group.

4. The activation coefficient of glutathione reductase in erythrocytes and liver was closely related to dietary riboflavin content; that of skin responded maximally even in the least-severelydepleted animals.

5. Hepatic and renal flavin contents were directly proportional to dietary riboflavin, FAD being conserved at the expense of ribotlavin and FMN. ATP: riboflavin 5-phosphotransferase (flavokinase; EC 2.7.1.26) activity was reduced, even in the least-severely deficient animals; ATP: FMN adenylyltransferase (FAD pyrophosphory1ase; EC 2.7.7.2) was increased in liver, but only in the most-severely-deficient animals.

6. Hepatic succinate: (acceptor) oxidoreductase (succinate dehydrogenase; EC 1. 3.99.1) activity fell sharply between 1·5 and 0·5 mg riboflavin/kg diet, producing an S-shaped dose-response curve; it showed smaller or less specific changes in other tissues such as brain, skin and intestine. NADH: (acceptor) oxidoreductase (NADH dehydrogenase; EC 1.6.99.3) activity declined in liver and intestine, but not in skin or brain.

7. Theactivation coefficient of glutathione reductase was correlated strongly with nearly all the riboflavin-sensitive variables measured, once equilibrium had been reached in this chronic deficiency model, and it was particularly strongly correlated with hepatic and renal FAD levels. Under equilibrium conditions, therefore, it appears to represent a good index of the extent of riboflavin deficiency, and significant changes in flavin levels and enzymes in the internal organs were detected even under conditions of marginal deficiency, associated with relatively small increases in the activation coefficient.
Fibre and bowel transit times
Authors: Gear J. S. S. , Brodribb A. J. M. , Ware Alison , Mannt J. I.
Published: June 2005

1. Bowel transit time has been investigated in vegetarians and non-vegetarians and related to dietary fibre intake and the presence of diverticular disease.

2. Vegetarians who have less diverticular disease than non-vegetarians have more rapid transit times.

3. Subjects with total dietary fibre intake of more than 30 g/d all had transit times of less than 75 h whereas 38% of those eating less had transit times exceeding 75 h and varying up to 124 h.

4. Individuals with diverticular disease were found to have faster transit times than those without the disease.

5. The colon may respond to a fibre-depleted diet either by becoming hyperactive and prone to diverticular disease or by becoming hypoactive leading to constipation.
Energy requirements of antarctic sledge dogs
Authors: Campbell I. T. , Donaldson J.
Published: June 2005

1. Eighteen male sledge dogs were weighed immediately on removal from their sheltered winter quarters at Halley Bay, Antarctica (75° 31′s, 26° 42′W) and weekly thereafter for 14 weeks. The first 2 weeks they were tethered and inactive and the following 12 weeks travelled an average of 10.9 km/d fully laden. Daily energy intake during winter and while tethered averaged 18–25 MJ/d and while travelling 13.9 MJ/0d.

2. Mean weight loss during the 2 weeks of inactivity was 2.3 kg despite an energy intake almost twice the recommended requirement. During the 12 weeks travelling energy intake decreased to 13.9 MJ/d but the weight loss stopped. Weather conditions at this time were becoming progressively milder.

3. The evidence suggests that sledge dogs are capable of high levels of cold-induced and possibly diet-induced thermogenesis and that these factors, particularly the former should be taken into account when designing dog rations and feeding schedules.
Degradation of maize protein in rumen contents Influence of ammonia concentration
Authors: Anna Níkolić J. , Filipović R.
Published: June 2005

1. The influence of ammonia concentration on the distribution of nitrogen derived from opaque-2 maize uniformly-labelled with15N has been investigated during short-term in vitro incubation of bovine rumen contents.

2. Less15N derived from maize was found in the non-protein-N (NPN) fraction during incubation without added NH3than with added NH3, due entirely to differences in the amount of N derived from maize in the NH3fraction.

3. From calculations based on the transfer of N derived from maize to the NPN pool and to a bacterial fraction, it was concluded that degradation of maize protein was not influenced by NH3concentration within the examined limits.

4. The decrease in relative amount of N derived from maize in the NH3fraction at low concentrations of NH3, together with evidence for an increased fractional turnover rate of NH3-N suggests that a deficient supply of NH3is compensated for by increased catabolism of nitrogenous compounds derived from the rumen micro-organisms.
Selenium metabolism in the dairy cow: the influence of the liver and the effect of the form of Se salt
Authors: Symonds H. W. , Sansom B. F. , Mather Denise L. , Vagg M. J.
Published: June 2005

1. Six adult Friesian cows were given 75Se as either 75SeO32− or 75SeO42− intravenously. Five of the cows had cannulas in an hepatic vein, the portal vein and one carotid artery to enable the uptake of 75Se by the liver to be measured. Radioactive balance studies were carried out on two of the cows given 75SeO32− and two given 75SeO42−. A seventh cow was given an oral dose of 75Se-labelled barley and the excretion of 75Se in faeces, urine and milk was measured for 14 d.

2. After the injection of 75SeO32− plasma 75Se concentration decreased during the first 30 min with a mean half-life (t½) of 15.6 min. From 30 to 60 min after dosing the concentration of radioactivity increased to reach approximately 50% of the level present 2 min after dosing. Following the injection of 75SeO42− the 75Se was cleared with a mean t½ of 28.5 min during the first 30 min and plasma radioactivity increased only slightly during the next 30 min.

3. During the phase of rapid clearance of 75Se after the injection of 75SeO32− the hepatic venous 75Se concentration was approximately 5% lower than portal veous 75Se concentration. During the period when plasma 75Se activity was increasing the activity in hepatic venous plasma was 3% greater than portal activity. Of the 75Se cleared from plasma after injecting 75SeO32− 40% was calculated to be removed by the liver.

4. After intravenous dosing with 75SeO32− or 75SeO42− approximately 9.5 and 17.0% respectively of the dose injected was excreted in faeces and 10% in urine within 14 d. Almost three times as much 75Se was excreted in urine and 3.5 times as much in faeces during the first 24 h after dosing with 75SeO42− as after 75SeO32−.
Effect of zinc deficiency on appetite and plasma amino acid concentrations in the rat
Authors: Wallwork J. C. , Fosmire G. J. , Sandstead H. H.
Published: June 2005

1. Levels of zinc in liver and plasma of the Zn-depleted rats fluctuated with the feeding cycle and were significantly higher at the bottom than at the top of the cycle. As Zn deficiency became more severe fluctuations in plasma Zn diminished. Concentrations of Zn in liver, in contrast to levels in plasma and femur, were not markedly lowered by day 15.

2. In contrast to udlib.-fed (AL) and overnight-fasted (OF) controls, some pair-fed (PF) controls had elevated levels of Zn in liver and plasma.

3. Intakes of water and food were sigdicantly correlated in Zn-deficient rats. Packed cell volumes were significantly higher for Zn-depleted than for AL and PF rats.

4. Food intakes and plasma glucose concentrations were related in AL, OF and PF control rats but not in Zn-deficient rats.

5. At day 15 of Zn deficiency the order of total plasma amino acid concentrations in the groups of rats was AL > Zn-deficient > OF > PF. Many of the differences between the AL and OF groups for individual plasma amino acids also appeared in the Zn-deficient group at the top and bottom of the feeding cycle. Differences in individual amino acid conmntrations at the top and bottom of the feeding cycle tended to be opposite in the PF and the Zn-ddicient group. Levels of tyrosine and tryptophan in plasma were correlated (P ≶ 0.05) with the cyclic feeding pattern of the Zn-deficient group; however, the ratios tryptophan or tyrosine: sum of other large neutral amino acids did not correlate significantly with the eating habits of Zndeficient rats.
Studies on the nutrition of salmonid fish. The magnesium requirement of rainbow trout (Salmo gairdneri)
Authors: Knox D. , Cowey C. B. , Adron J. W.
Published: June 2005

1. Rainbow trout (Salmo gairdneri) of mean initial weight 35 g were given one of five experimental diets for 20 weeks. The diets contained (g/kg dry diet) 15 calcium, 10 phosphorus and graded levels of magnesium from 0.04 (diet no. 1) to 1.0 (diet no. 5). In a second experiment rainbow trout of mean initial weight 16 g were given one of six experimental diets for 20 weeks. The diets contained (g/kg dry diet): Ca (40), P (30) and levels of Mg from 0.06 (diet no. 6) to 2.0 (diet no. 11).

2. In both experiments weight gains were lowest in those trout given diets containing the basal levels of Mg (diet no. 1 and diet no. 6) but increased with increasing dietary Mg concentration. In neither experiment was there any further increase in weight gain once the Mg concentration reached 0.25–0.5 g/kg dry diet; weight gain reached a plateau at this dietary Mg level.

3. The following trends occurred in serum electrolyte concentrations as dietary Mg increased. Mg increased in both experiments, in Expt 2 it reached a maximum of 1 mmol/l when the diet containted 0.5 g Mg/kg and did not increase further; sodium was positively correlated in both experiments; potassium decreased and in Expt 2 reached a plateau minimum of 1.7 mmol/l at a dietary Mg concentration of 0.5 g/kg; Ca and P altered little in either experiment.

4. In both experiments renal Ca concentrations were greatly increased in trout given diets lacking supplementary Mg; they fell to low levels (3–5 mmol/kg) when diets conained 0.15 g Mg/kg or more. Renal K and P concentrations were negatively correlated with dietary Mg in Expt 2; other electrolytes measured were not altered in concentration by the treatments used.

5. Extracellular fluid volume (ECFV) of muscle was negatively correlated with dietary Mg. In Expt 2 it reached a minimal or normal value at 0.5 g Mg/kg diet and did not decease further. Muscle Mg concentration increased with diet Mg in both experiments and muscle K concentration was also correlated with diet Mg in Expt 2. These changes were related to the shift in muscle water. In Expt 1, P concentration was decreased with increasing diet Mg but in Expt 2 its concentration increased, these changes may have been connected with the three-fold difference in dietary P in the two experiments.

6. By contrast with skeletal muscle, Mg levels in cardiac muscle increased at low dietary Mg intakes.

7. Concentrations of electrolytes in liver did not alter with dietary treatments used.

8. The results show that Mg requirement of rainbow trout is met by a diet containing 0.5 g Mg/kg diet.
Changes in the concentrations.of the minor Constituents of goat's milk during starvation and on refeeding of the lactating animal and their relationship to mammary gland metabolism
Authors: Chaiyabutr N. , Faulkner Anne , Peaker M.
Published: June 2005

1. Changes in the concentrations of the minor constituents of goat's milk were observed during 48 h starvation and on refeeding.

2. The concentrations of hexose phosphate and UDP-hexoses increased during starvation and decreased on refeeding.

3. The concentrations of phosphoenolpyruvate and glycerate 3-phosphate decreased during starvation and increased on refeeding.

4. Isocitrate: 2-oxoglutarate increased during starvation and decreased on refeeding.

5. Changes in the minor constituents of milk can be explained in terms of the metabolic changes occurring in the mammary gland during starvation. It is proposed that changes in the concentrations of these metabolites in milk reflect changes in their concentrations in the cytosol or Golgi vesicles of the mammary gland.
The effect of amino acid imbalance on nitrogen retention (biological value) in rats
Authors: Eggum B. O. , Knudsen K. E. Bach , Jacobsen Ingeborg
Published: June 2005

1. Three series of nitrogen balance experiments were performed with growing rats to test the effect of amino acid imbalance on protein utilization. In Expt 1 egg protein was fed as a basal diet and supplemented with one amino acid at a time in the amounts originally found in egg protein. In Expt 2 the procedure was repeated with a barley diet, and in Expt 3 egg and potato proteins were fed together in various combinations.

2. Doubling the single amino acids, especially arginine, in an egg-protein diet reduced biological value (BV) markedly. Also the branched-chain and the basic amino acids reduced BV significantly. In the barley-based diets negative effects were also observed when the concentration of the single amino acid was doubled. However, it was assumed that the observed deleterious effects of amino acid excess were partly due to an exaggerated lysine deficiency in the barley protein when non-limiting amino acids were added.

3. The results with various combinations of egg and potato proteins showed that as potato protein was increased true protein digestibility decreased linearly, whereas BV decreased Curvilinearly. Maximum protein utilization was obtained with egg protein alone.
Serum thymic hormone activity in genetically-obese mice
Authors: Chandra R. K. , Heresi Gloria , Au B.
Published: June 2005

1. Serum thymic hormone was assayed in genetically-obese (C57B1/6J ob/ob) mice and lean controls (+/+, +/−) of the same strain.

2. The thymic hormone activity was higher in the majority of the obese animals compared with non-obese mice.

3. The number of antibody-forming cells in the spleen expressed as a proportion of the total mononuclear cells was increased in the obese mice.

4. It is suggested that obesity is associated with significant changes in the thymic hormone levels which may alter the relative proportion of lymphocyte subsets and cell-mediated immunity.
Studies on the response ofLactobacillus caseito folate vitamin in foods
Authors: Phillips D. R. , Wright A. J. A.
Published: June 2005

1. Folate was measured microbiologically withLactobacillus caseiin extracts from a range of different foods at two incubation pH values, 6·2 and 6·8.

2. The values for folate content obtained at pH 6·2 were, in several instances, considerably higher than at pH 6·8. The ‘positive drift’ seen in the values for dilutions incubated at pH 6·8 were absent from results at pH 6·2.

3. A comparison was made of the ability of the two main sources (hog kidney and chicken pancreas) of deconjugase enzyme to produce measurable folate and the hog-kidney enzyme was shown to produce consistently higher values.

4. The results presented here will have significance for studies of folate intake using calculations from food composition tables, in the light of the apparent discrepancy between calculated folate intake and the recommended daily allowances for the UK.
Effect of the nature and amount of dietary energy on lipid composition of rat gingival tissue
Authors: Das Salil K. , Elliott Munalula L. , King Halifax C.
Published: June 2005

1. The effect of the nature and amount of dietary energy on the lipid composition of rat gingival tissue was studied. Male weanling rats were given one of three iso-energetic diets: high-carbohydrate, high-protein and extremely high-protein, or a fourth high-fat diet, for 49 d.

2. The high-carbohydrate, extremely high-protein and high-fat diets caused significant increases in the gingival levels of total lipids compared with the normal-protein diet. These increases in total lipids were due primarily to increases in the levels of triglycerides and cholesterol esters. There were no significant differences in the fatty acid compositions of either non-polar or polar lipids among rats given the high-carbohydrate diet and those given the high-protein diet.

3. A comparison of the fatty acid composition of lipids of rats given the extremely high-protein diet and the other two iso-energetic diets revealed that the proportion of palmitic acid was higher and the proportion of oleic acid was lower in animals given the extremely high-protein diet than in animals given the other two diets. Compared with the three iso-energetic low-fat diets, the high-fat diet caused decreases in the proportion of palmitic and palmitoleic acids and increases in the proportion of linoleic, arachidonic and docosapentaenoic acids in total fatty acids of both non-polar and polar lipids. It should be noted that the high-fat diet contained a high proportion of linoleic acid and it is expected that this diet would raise the 18:2 fatty acid content of the lipids and also would raise the 20:4 and 22:5 levels as 18:2 is an essential fatty acid and will, with its metabolites, be directly incorporated into tissue lipids.
The effect of periconceptional supplementation on blood vitamin concentrations in women at recurrence risk for neural tube defect
Authors: Schorah C. J. , Wild J. , Hartley R. , Sheppard S. , Smithells R. W.
Published: June 2005

1. We measured erythrocyte folic acid and riboflavin, serum folic acid and leucocyte vitamin C in women at high risk for neural tube defect (NTD) recurrence who were receiving periconceptional vitamin supplementation, before they received extra vitamins, after 28 d of supplementation and at the 8th week of pregnancy. Blood vitamin concentrations in unsupplemented high-risk women were also compared with the values found in unsupplemented low-risk women.

2. Vitamin supplementation with Pregnavite Forte F (Bencard®) raised the mean values for all vitamins measured by the 8th week of pregnancy. Mean erythrocyte folic acid rose from 250 to 478 ng/ml; plasma folic acid from 8·4 to 26·1 ng/ml; leucocyte vitamin C from 1·82 to 3·21 μg/ml blood; erythrocyte riboflavin (glutathione reductase (EC 1.6.4.2) activation ratio) from 1·08 to 1·04. All women receiving supplements had increased their serum and erythrocyte folic acid levels above the highest values found in women in an earlier study, who subsequently gave birth to children with NTD. Not all women, however, increased their leucocyte ascorbic acid or erythrocyte ribflavin levels above the highest values.

3. When vitamin concentrations in unsupplemented high-risk women were compared with levels in unsupplemented women at low risk for NTD, no significant differences were found in the mean values. However, a significantly higher proportion of high-risk compared with low-risk women had erythrocyte folic acid and leucocyte vitamin C values on or below the 5th percentile of the adult normal range.

4. The effectiveness of Pregnavite Forte F (Bencard®) for increasing maternal vitamin reserves is discussed with a view to preventing NTD and the possibility of identifying groups at risk for NTD because of low blood vitamin levels is considered.
Reduced plasma half-life of radio-labelled 25-hydroxyvitamin D3in subjects receiving a high-fibre diet
Authors: Batchelor A. J. , Compston Juliet E.
Published: June 2005

1. The plasma disappearance of3H-labelled 25-hydroxyvitamin D3(25(OH)D3) was studied in healthy volunteers on normal and high-fibre diets, using3H-labelled tracer doses given intravenously.

2. The mean (±SEM) plasma half-life in the high-fibre-diet group was 19·2±1·7d, which was significantly shorter than in the group on normal diets (27·5±2·1 d,P< 0·02).

3. This finding suggests that a high-fibre diet leads to enhanced elimination of 25(OH)D3by an action within the intestinal lumen. This may involve interference with an enterohepatic circulation of the metabolite, perhaps by binding of 25(OH)D3to dietary fibre.

4. The reduced plasma half-life of3H-labelled 25(OH)D3associated with a high-fibre diet may explain the development of vitamin D deficiency in Asian immigrants with normal exposure to u.v. light.
Food intolerance: a community survey
Authors: Burr M. L. , Merrett T. G.
Published: June 2005

1. A questionnaire inquiring about food intolerance was sent to a random sample of the electorate in a small South Wales town. Replies were received from 170 men and 305 women, the response rates being 87 and 93% respectively.

2. Adverse effects of some food were reported by 19% of men and 26% of women, or 14 and 18% respectively if minor digestive symptoms are excluded. Certain foods were thought to cause non-abdominal symptoms by 4% of men and 10% of women, and vomiting, diarrhoea or abdominal pain by 11% of men and 10% of women.

3. Plasma IgE was measured in a random subset of ninety-nine women and found to be significantly lower in those with major symptoms than in the rest. This suggests that allergy is probably not a common cause of food intolerance.
The effects of energy intake and dietary protein on nitrogen retention, growth performance, body composition and some aspects of energy metabolism of baby pigs
Authors: Campbell R. G. , Dunkin A. C.
Published: June 2005

1. The effects of level of feeding of either a protein-adequate or a protein-deficient diet on nitrogen retention (NR), growth performance, body composition and some aspects of energy utilization in pigs growing from 1·8 to 6·5 kg live weight (LW) were investigated in two experiments.

2. In Expts 1 and 2 piglets were given a protein-adequate diet at four levels of intake (0·93, 1·44, 1·83 and 2·30 MJ gross energy (GE)/kg LW0·75 per d) and a protein-deficient diet at five levels of intake (1·14, 1·38, 1·68, 1·95 and 2·30 MJ GE/kg LW0·75 per d) respectively.

3. For pigs given the protein-adequate diet (Expt 1) NR was linearly (P < 0·001) related to energy intake (EI) and independent of N intake (NI). NR in pigs given the protein-deficient diet (Expt 2) was linearly (P < 0·001) related to NI and independent of EI.

4. Average daily LW gain responded linearly to increases in EI in both experiments. However, at equivalent levels of EI pigs given the protein-adequate diet exhibited more rapid and efficient growth than those given the protein-deficient diet. The results also indicated an interaction between the effects of EI and dietary protein content for feed conversion efficiency.

5. Body fat at 6·5 kg LW increased in a curvilinear fashion with increasing EI in both experiments. However, over the range of EI tested (from approximately 1·8 to 4·6 times energy for maintenance) body fat increased by 153% in Expt 1 and by only 27% in Expt 2. Pigs given the protein-deficient diet were also markedly fatter than those given the protein-adequate diet. Body protein at 6·5 kg LW decreased (P < 0·01) with increasing EI in Expt 1 but was unaffected by EI in Expt 2.

6. As estimated by multiple regression analysis, the values for the efficiency of energy utilization for protein (kp) and fat (kf) deposition were 0·76 and 0·78 respectively in Expt 1 and 0·42 and 0·89 resepctively in Expt 2. The estimates of metabolizable energy required for maintenance were 445 and 532 kJ/kg LW0·75 per d for Expts 1 and 2 respectively.
Trace-nutrient-binding proteins in milk and the growth of bacteria in the gut of infant rabbits
Authors: Cole C. B. , Scott K. J. , Henschel M. J. , Coates M. E. , Ford J. E. , Fuller R.
Published: June 2005

1. The influence of trace-nutrient-binding proteins on the growth of coliforms, streptococci and lactobacilli in the gastrointestinal tract was examined in neonatal rabbits delivered germ-free and dosed with an artificial flora (ESL), or born conventionally and dosed with ESL or rabbit faeces.

2. In the stomach and small intestine of both gnotobiotic and conventional animals the counts of coliforms were usually atypically high and those of streptococci were always low. In the colon the counts of coliforms and streptococci were high. Lactobacilli usually became established in the gut of the gnotobiotic animals but were not found in the conventional rabbits.

3. Sterilization (freeze-drying followed by γ-irradiation) of the milk decreased its capacity to bind added iron by 45% and vitamin B12by 30%. When compared with raw milk, feeding of radiation-sterilized milk did not affect the viable count of coliforms and streptococci in the gut of gnotobiotic animals.

4. Saturating the nutrient-binding proteins in milk with Fe, folic acid and vitamin B12had no effect on the numbers of coliforms, streptococci and lactobacilli recovered from the intestine.
The influence of protein:energy value of the ration and level of feed intake on the energy and nitrogen metabolism of the growing pig
Authors: Berschauer F. , Close W. H. , Stephens D. B.
Published: June 2005

1. The nitrogen balances of thirty-six individually-housed, entire male pigs (body-weight range 19–50 kg) were measured over 7 d periods when the animals were kept initially at an environmental temperature of 22° and then at 10° while fed on rations containing 153, 201 and 258 g crude protein (N × 6·25; CP)/kg dry matter (DM). The respective metabolizable energy (ME) contents were 16·29, 16·96 and 17·24 MJ/kgDM. Each ration was given at three levels, 20, 35 and 50 g feed/kg body-weight per d. The animals fed on the 20 and 35 g/kg feeding level were catheterized and blood samples withdrawn on two consecutive days within the N-balance periods for the determination of blood urea (BU) concentration both before and at hourly intervals for 7 h following the morning feed.

2. An increase in feed intake resulted in a significant increase in N retention (NR) at each environmental temperature. However, NR as a proportion of N intake was higher the lower the protein content of the ration. With the exception of the animals fed on the low-protein ration, NR at any given feed intake was lower at 10° than at 22° and these differences were reflected in the animal's body-weight gain.

3. Values for the fasting N metabolism (Nf), calculated from the relationship between NR and intake of digestible N (IDN), were temperature-dependent. At 22°, a constant Nfvalue of 0·255 g N/kg body-weight0·75per d was found appropriate, while at 10° Nfincreased with increase in protein content of the ration from 0·380 on the low protein ration to 0·533 and 0·753 g N/kg body-weight0·75per d on the medium- and high-protein rations respectively.

4. The efficiency of N utilization (kN) reflected the differences in the relationships between NR and IDN. At 22° the relationship was curvilinear so thatkNdecreased with increase in both the level of feed intake and the protein content of the ration. At 10° the relationship was linear, hencekNwas independent of feed intake within rations. However, it decreased from 0·909 to 0·679 as the protein content of the ration was increased.

5. The concentration of BU attained a maximal value some 3–5 h after the ingestion of the feed, with the values at 10° being higher than those at 22°. BU increased as the level of protein in the ration increased but decreased with the level of feed intake when dietary protein concentration was held constant. There was a significant correlation between BU andkN, indicating that BU is a useful criterion for assessing the efficiency of N utilization.
A vegan regimen with reduced medication in the treatment of hypertension
Authors: Lindahl Olov , Lindwall Lars , Spångberg Alf , Stenram ÅKe , Öckerman Per Arne
Published: June 2005

1. Twenty-nine patients who had suffered from essential hypertension for an average of 8 years, all receiving long-term medication for hypertension, were subject to therapy with vegan food for 1 year. In almost all cases medication was withdrawn or drastically reduced. There was a significant decrease in systolic and diastolic blood pressure. A number of reported symptoms disappeared.

2. There was a significant improvement in a number of clinical variables as well as a significant change in various biochemical indices such as urea, haptoglobin, cholesterol and triglyceride concentrations in blood.

3. Subjectively all patients reported improvement.

4. Selected patients, with a fear of side-effects of medication, who are interested in alternative health care might replace conventional medication with this dietary regimen.
Major influences on median energy and nutrient intakes among teenagers: a Tasmanian survey
Authors: Woodward David R.
Published: June 2005

1. This report explores the characteristics that influenced median intakes of energy and ten nutrients in a representative sample of 1055 adolescents (11–16 years) in Tasmania, Australia.

2. Among girls, the characteristic with greatest influence on intakes was different for different nutrients. Thus, median intakes of fat, iron, thiamin and niacin-equivalent were lower in heavier, fatter girls. Girls from larger families consumed more riboflavin, while girls with poorly educated mothers consumed less vitamin A. Girls who regularly took vitamin supplements had higher median intakes of (food-derived) calcium.

3. Among boys the increase of intakes of energy and nutrients with age overshadowed the influence of other characteristics.

4. Among younger boys the characteristic with greatest influence varied. Those with highly educated fathers had lower median intakes of energy and carbohydrate; those who exercised vigorously consumed more fat; those who smoked ‘heavily’ (> 10 cigarettes in the previous week) consumed more thiamin and niacin-equivalent.

5. Among older boys the characteristic with greatest influence varied. Those who drank ‘heavily’ (> five glasses in the previous week) had higher intakes of energy and fat. Those from professional–managerial households consumed more thiamin.

6. For vitamin C, there was no sex difference in intakes. Social status had the greatest influence, with children from professional–managerial households eating more.

7. Food choices underlying these differences in energy and nutrient intakes were explored.
Fatty acid composition of platelet phospholipids in non-insulin-dependent diabetics randomized for dietary advice
Authors: Lopez-Espinoza I. , Howard-Williams J. , Mann J. I. , Carter R. D. , Hockaday T. D. R.
Published: June 2005

1. Two groups of patients with non-insulin-dependent diabetes mellitus (NIDDM), with dietary advice randomized between a low-carbohydrate (LC) diet and a modified-fat (MF) diet, were followed to determine the effect of diet on phospholipid fatty acid composition of platelets and on development of retinopathy in the 7 years following diagnosis. There was a tendency for retinopathy to occur more frequently in those randomiEd to the LC diet. This difference was not statistically significant, and fatty acid composition of platelets did not differ significantly in those with and without retinopathy.

2. Linoleic acid values from platelet phospholipid fatty acids were significantly higher in NIDDM on an MF diet compared with an LC diet.

3. There was no difference between the two dietary subgroups with respect to platelet arachidonic acid, but this was lower in the whole diabetic population when compared with non-diabetics.

4. The arachidonic acid values correlated with neither glycosylated haemoglobin nor mean glycaemia.

5. Significant correlation between the fatty acid values for platelets and plasma cholesterol esters was found only for 16:0.