bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends in individual fat consumption in the UK 1900–1985
Authors: Stephen Alison M. , Sieber Glynis M.
Published: June 2005

Mortality from coronary heart disease is decreasing in a number of Western countries, although the pattern of the decrease differs from country to country. In the UK the mortality rate from coronary heart disease has declined since 1979, whereas in the USA mortality from this disease began to fall in 1968 and has continued since that time. Of many factors suggested as reasons for the decline, diet has been implicated, particularly dietary fat intake. However, food balance information suggests little change in fat intake. A recent examination of all published studies from the USA where individual fat intake has been reported indicated that fat intake in that country has fallen steadily since the mid 1960s. The present study describes a similar compilation of all published studies from the UK giving individual fat intakes. Ninety-seven studies, representing information for 24045 individuals, were used. Studies ranged in size from two to 3581 individuals and were drawn from all regions of the UK. Most studies used 7 d weighed intakes as the method of dietary assessment. Quadratic regression equations were applied to the fat intakes from all studies over time, with each study weighted by the number of individuals surveyed. Data were also divided into 10-year periods and weighted fat intakes for each decade were calculated. Data were expressed for all studies, then subdivided into males, females, children and the elderly. Comparisons between Scotland and the South-East of England were made. Results indicate that fat represented 30% or less of dietary energy in the UK until the 1930s, when it began to rise. This rise was curtailed by rationing during and after the Second World War, after which the rise continued, reaching a plateau of about 40% energy in the late 1950s, with little change until the late 1970s. Trends were similar in all age-groups, but less change has occurred recently in Scotland compared with South-East England. These results differ from the pattern in the USA and suggest that if greater changes in mortality from coronary heart disease are to be seen in the UK a greater reduction in dietary fat intake will have to occur.
An in vitro procedure for studying enzymic dephosphorylation of phytate in maize-soyabean feeds for turkey poults
Authors: Zyla Krzysztof , Ledoux David R. , Garcia Angel , Veum Trygvel
Published: June 2005

Anin vitromethod was developed to predict inorganic P release from maize-soyabean poultry feeds containing supplemental phytase (EC31·3·8), and to quantify the effect of acid phosphatase (EC3·1·3·2), fungal protease (EC3·4·23·6) andAspergillus nigercellulase (EC3·2·1·4) on phytate dephosphorylation. Pepsin (EC3·4·23·1) and pancreatin digestion periods were preceded by a 30 min pre-incubation at pH 5·25 to simulate digestion in the crop of poultry. Pancreatin digestion was carried out in dialysis tubing, with a ratio of about 1:25 (v/v) between the digesta and dialysing medium, to simulate gradient absorption from the duodenum. The feed:water ratio was kept within physiological limits and a constant proportion of feed weight to digestive enzymes was maintained. There was a linear response to increasing dosages of phytase up to 1000 phytase units (FTU)/kg feed, and to increasing phosphate concentration in feeds.In vivovalidation was performed with growing turkeys (1–3 weeks) fed on diets containing 12 g Ca/kg and 0, 500 or 1000 FTU phytase/kg in a factorial arrangement with 0, 1, 2 or 3 g supplemental phosphate/kg (from KH2PO4). After a simple transformation (variable/in vitroP =f(in vitroP)), amounts of P hydrolysed from feed samples byin vitrodigestions correlated with 3-week body-weight gain (R0·986,P< 0·0001), toe ash (R0·952,P< 0·0001), feed intake (R0·994,P< 0·0001) and feed efficiency (R0·992,P< 0·0001). The dephosphorylating ability of phytasein vitrowas significantly enhanced (P< 0·05) by the addition of acid phosphatase. Fungal acid protease andAspergillus nigercellulase also enhanced the dephosphorylation processin vitro.
Dietary change after smoking cessation: A prospective study
Authors: Thompson R. L. , Pyke S. D. M. , Scott E. A. , Thompson S. G. , Wood D. A.
Published: June 2005

A population sample of 375 men and women cigarette smokers were recruited to take part in a prospective study of smoking cessation to test the hypothesis that stopping smoking is associated with an increased consumption of the essential fatty acid linoleic acid, which explains the concomitant reduction in risk of coronary heart disease. Diet was assessed using a 10 d weighed record in 301 smokers at baseline, 153 at 4-month follow-up, of whom twenty-six had quit smoking, and 122 at 1-year follow-up, of whom twenty had quit. Compared with continuing smokers, those who had quit at the 4-month follow-up (mean 10 and 13 weeks for men and women respectively) had statistically significant increases in body weight (5%), energy intake (13%), total dietary fat (24 %), all specific types of dietary fat (26% polyunsaturated fat, 26% linoleic acid, 30% eicosapentaenoic acid, 23% monounsaturated fat and 22% saturated fat) and vitamin E intake (19%). The foods which appeared to contribute to increases in energy and fat intakes at the 4-month follow-up were vegetable oils and polyunsaturated margarines, processed meats and meat pies. By follow-up at 1 year (mean time since quitting 31 and 41 weeks for men and women respectively) there were no detectable differences in energy and total fat intakes. However, intakes of eicosapentaenoic acid and pteroylglutamate (folate) were statistically significantly higher in the quitters compared with the continuing smokers (37% for eicosapentaenoic acid and 16% for folate). We conclude that the short-term increase in dietary intake of linoleic acid, which is not sustained by 1 year, cannot explain the reduction in risk of coronary disease following smoking cessation.
Recovery of inulin from Jerusalem artichoke (Helianthus tuberosus L.) in the small intestine of man
Authors: Knudsen Bach K. E. , Hessov I.
Published: June 2005

The recovery of inulin, a naturally occurring β(2→l)-fructan isolated from Jerusalem artichoke (Helianthus tuberosus L.), in the small intestine of man was studied in ileostomy subjects. The ileostomists were given a low-dietary-fibre diet based on white wheat bread and virtually free of inulin, and the same diet with the addition of 10 g and 30 g inulin product respectively, and the recovery and mean transit time (MTT) of inulin were estimated by tracking inulin in ileal effluent. The recovery of inulin was approximately 87% at both ingestion levels. MTT was 4·9 (SE 0·6) h at an intake of 10 g inulin product decreasing to 3·4 (SE 0·3) h at an intake of 30 g Inulin product. A significant change in the fructose: glucose ratio of inulin from ingestion (4·1) to recovery in ileal effluent (4·5–4·7) and a lower recovery of the glucose residue than of the fructose residue of inulin indicate that the low-molecular-weight inulins are more sensitive to hydrolysis than the high-molecular-weight fragments. The loss of inulin during passage through the small intestine is presumably due to hydrolysis by either acids or enzymes and to microbial degradation by the microfiora permanently colonizing the distal small intestine. The concentrations of lactic acid (LA) and short-chain fatty acids (SCFA) in frequently collected ileal effluents on the control day were approximately 6 mmol/l and approximately 55 mmol/l respectively. During periods with inulin ingestion the concentration of LA increased to 18–26 mmol/l (P < 0·052), while the concentration of SCFA ran converse and decreased to 18–32 mmol/l (P < 0·023). The osmotic loads (68 and 204 mosmol/l) associated with the ingestion of inulin product caused minor malabsorption of low-molecular-weight sugars.
Differences in propionate-induced inhibition of cholesterol and triacylglycerol synthesis between human and rat hepatocytes in primary culture
Authors: Lin Yuguang , Vonk Roel J. , Slooff Maarten J. H. , Kuipers Folkert , Smit Martin J.
Published: June 2005

Propionate is a short-chain fatty acid formed in the colon and supposedly involved in the cholesterol-lowering effect of soluble fibre. To explore the underlying mechanism(s) of this fibre action, we have used human hepatocytes in primary culture to study the effects of propionate on hepatic lipid synthesis. Initial experiments with mevalonate and mevinolin, a competitive inhibitor of hydroxymethylglutaryl (HMG)-CoA reductase (EC1·1·1·88) were performed to evaluate basic regulatory mechanisms in these cells; results were compared with those obtained with rat hepatocytes. Incubation for 24 h with mevalonate caused a similar, concentration-dependent inhibition of [14C]acetate incorporation. into cholesterol in human and rat hepatocytes. Likewise, mevinolin (100 μmol/l) inhibited the formation of cholesterol from radiolabelled acetate by about 80% in cells from both species. Propionate inhibited cholesterol as well as triacylglycerol synthesis from [14C]acetate with a similar concentration-dependency in rat hepatocytes. Fifty percent inhibition was obtained at a propionate concentration of only 0·1 mmol/l· This propionate-induced inhibition was not affected by a 100-fold excess of unlabelled acetate. Human hepatocytes were much less susceptible in this respect: propionate concentrations of 10–20 mmol/l were required to obtain similar inhibitory effects in these cells, i.e. values greatly exceeding reported portal propionate concentrations in humans. The results suggest the existence of differences in the regulation of hepatic cholesterol (and triacylglycerol) synthesis between human and rat liver cells. These results do not support the hypothesis that the fibre-induced decrease in plasma cholesterol concentration in man is mediated by a direct effect of propionate on hepatic cholesterol synthesis.
Effect of oat saponins and different types of dietary fibre on the digestion of carbohydrates
Authors: Önning G. , Asp N.-G.
Published: June 2005

The effects of oat saponins (a mixture of avenacosides A and B) and dietary fibre (cellulose and guar gum) on the disaccharidase activities in the proximal small intestine of the rat were investigated. The influence of avenacosides A and B on the activity of disaccharidases and α-amylase (EC3·2·1·1) was also studiedin vitro. In vivo, oat diets with three avenacoside contents (negligible, normal and twice normal) were used. No significant differences in sucrase (EC3·2·1·48), maltase (EC3·2·1·20), trehalase (EC3·2·1·28) and lactase (EC3·2·1·21) activities were found between the oat groups after 19 d feeding. The rats that were given cellulose tended to have higher disaccharidase activities compared with the other groups. The avenacosides inhibited the lactase activity significantlyin vitrowhile no or small effects on the other disaccharidases were found. In contrast, thein vitrohydrolysis of starch by α-amylase was increased in the presence of saponins, probably due to their detergent effect. Thus, thein vitrostudies showed that the avenacosides could influence the enzyme activities.In vivo, these effects are probably minor due to the low avenacoside concentrations found in oats.
The thermic effect of food in normal-weight and overweight pregnant women
Authors: Bronstein Michele N. , Mak Rosa P. , King Janet C.
Published: June 2005

A defective thermic response to food may be an energy-sparing adaptation in both obesity and pregnancy. To evaluate the combined effect of obesity and pregnancy on postprandial thermogenesis, the thermic effect of food was assessed for a 240 min period following a high-carbohydrate meal and a typical mixed meal in nine normal-weight non-pregnant, eight overweight non-pregnant, eight normal-weight pregnant and six overweight pregnant women using indirect calorimetry. A test meal that provided 60% of each subject's measured daily requirement for basal metabolism was used. Pregnant women were studied during weeks 30–35 of gestation. Neither obesity nor pregnancy altered the thermic effect of food, although the response to the mixed meal was greater (P <0·01) than that to the high-carbohydrate meal in all cases. The mean responses for the high-carbohydrate and mixed meals were 26·9 (SD 6·0) and 30·1 (SD 6·2)% baseline energy expenditure respectively, and 7·4 (SD 1·6) and 8·3 (SD 1·6)% of the meal energy load respectively. Obesity and pregnancy were associated with hyperinsulinaemia (P <0·005) following both test meals, suggesting that postprandial thermogenesis was not altered by insulin resistance in this group. The incremental glucose response was elevated (P <0·001) in the pregnant women following both test meals; overweight women tended to have a greater incremental glucose response following the high-carbohydrate meal, but it was not significant (P = 0·065). These results do not provide evidence of an impaired thermic response to food in either overweight or third trimester pregnant women.
Determination of digestible energy values and fermentabilities of dietary fibre supplements: a European interlaboratory study in vivo
Authors: Livesey G. , Smith T. , Eggum B. O. , Tetens I. H. , Nyman M. , Roberfroid M. , Delzenne N. , Schweizer T. F. , Decombaz J.
Published: June 2005

The performance of methods to determine energy conversion factors for dietary fibre (DF) supplements and fermentability (D) values of their non-starch polysaccharides (NSP) was investigated. Heats of combustion, digestible energy (DE) and D values were determined on five DF supplements in five European laboratories on five separate occasions. In each instance the DF supplements were fed to juvenile male VVistar rats at two doses, 50 and 100 g/kg basal diet, for 3 weeks with food and faeces collected in the 3rd week. Among-laboratory variations in heats of combustion (DHC<) were <2%. DE values (kJ/g dry weight) at the upper and lower doses respectively were: 10·4 and 9·9 for a high-methoxyl apple pectin, 9·5 and 9·4 for a sugar-beet DF supplement, 12·2 and 12·7 for soyabean DF supplement, 38 and 4·0 for maize bran, and 0·3 and 0·3 for Solka-floc cellulose. Variations among laboratories, among occasions and among animals were <1, <2 and <2·5 kJ/g respectively. The among-occasion: among-laboratory variance ratio for DE was 0·5, suggesting the method performed equally well in all laboratories. There was no evidence of learning or fatigue in the performance of the method. D values were also independent of dose and at the high and lower doses were: pectin 0·92 and 0·95, sugar-beet NSP 0·68 and 0·68, soyabean NSP 0·86 and 0·88, maize bran 0·17 and 0·18, cellulose 0·07 and 0·06. Among-laboratory variance tended to increase with decreasing fermentability and ranged from 0·03 to 0·18. The DE and D data were not significantly different from a previously proposed relationship DE = 0·7 × DHc × D, where DHc is the heat of combustion of the supplement. We conclude that while the among-laboratory variation in the D of difficult-to-ferment NSP is too large for the reliable prediction of energy value the method for the direct determination of DE is both reproducible and repeatable, that DE is independent of dosage of DF supplement up to 100 g/kg diet, and that it is safe to discriminate between energy values with a precision of 3 kJ/g. The conversion of both DE and D to net metabolizable energy for the purpose of food labelling, tables and databases is described.
Absorption and endogenous excretion of phosphorus in growing broiler chicks, as influenced by calcium and phosphorus ratios in feed
Authors: Al-Masri M. R.
Published: June 2005

Absorption and endogenous excretion of P by male broiler chicks (14–29 d old) were quantitatively evaluated at different Ca: P ratios (1, 1:1; 2, 1·5:1; 3, 2:1; 4, 2·5:1) in four groups given experimental diets ad lib. The P content was the same in all diets. An isotope-dilution technique was used to determine endogenous faecal and renal excretion. Ca and P retentions in the whole body were estimated according to the comparative slaughter technique. P absorption was calculated from retention and endogenous excretion. Absorption and endogenous excretion of P amounted to (mg P/d per chick): 304, 270,160 and 158; and 135, 109, 31 and 30 in groups 1, 2, 3 and 4 respectively. Widening of the Ca:P ratio in the feed limited the P absorption. Availability of feed P amounted to (%): (1) 66, (2) 57, (3) 32 and (4) 30, and the amounts of absorbed P retained were (%): (1) 56, (2) 60, (3 and 4) 81. The increasing Ca concentration in the feed showed a greater effect on P absorption than on P retention. The ratios of relative retention to relative endogenous excretion of absorbed P were: (1) 1·27, (2) 1·50, (3 and 4) 4·26.
Nutrient intake and biochemical status of non-institutionalized elderly subjects in Norwich: comparison with younger adults and adolescents from the same general community
Authors: Wright A. J. A. , Southon Susan , Bailey Angela L. , Finglas P. M. , Maisey Susan , Fulcher R. A.
Published: June 2005

The Department of Health (1992) has recently stated that ‘Nutritional reviews concerning elderly people are especially constrained by lack of data’, and that much of the emphasis in the nutritional literature has been placed on the study of institutionalized, and often chronically ill, elderly subjects rather than the non-institutionalized elderly who form the majority of this population. The present study presents information on the dietary intake and biochemical status of non-institutionalized elderly subjects (68–73 and 74–90 years) and compares such data with those obtained for adult (20–64 years) and adolescent (13–14 years) populations living within the same community. Nutrient intakes and appropriate biochemical measurements of nutrient status, performed on fasting blood samples, were statistically examined and have been discussed in relation to potential age-related influences. The nutrient intake of elderly subjects was on a par with adolescents of corresponding sex but generally lower than that of adult counterparts. There were several significant differences in biochemical measurements of nutrient status between age groups. In general these did not suggest progressive age-related trends. However, there were significant suggestions of age-related increases in whole-blood glutathione peroxidase (EC1·11·1·9) activity, serum ferritin, plasma cholesterol, LDL and triacylglycerol concentrations and decreases in plasma HDL and ascorbic acid concentrations. The significance of these differences is discussed. An age-related difference (suggestive of a decline) in vitamin C status together with a difference (suggestive of an increase) in glutathione peroxidase activity may indicate an imbalance in the regulation of O2-derived free-radicals with ageing. These observations are worthy of a further study in the light of current thinking which relates the induction of a number of diseases to oxidative damage.
The effects of fasting on the thermogenic, metabolic and cardiovascular responses to infused adrenaline
Authors: Webber J. , Taylor J. , Greathead H. , Dawson J. , Buttery P. J. , MacDonald I.A.
Published: June 2005

The effects of fasting on the thermogenic, lipolytic and cardiovascular responses to adrenaline were examined in nine normal, young, non-obese subjects. Each subject attended for study after 12, 36 and 72 h fasting. After basal measurements adrenaline was infused at 25 ng/min per kg ideal body weight for 90 min. Fasting increased the thermogenic effect of the adrenaline (mean 14·6 (SE 1·7), 16·6 (SE 1·8), 22·6 (SE 1·6) J/:min per kg fat-free mass after 12, 36 and 72 h fasting respectively;P< 0·001, ANOVA). Basal plasma palmitate turnover increased with duration of fasting (1·48 (SE 0·22), 1·95 (SE 0·34) and 2·26 (SE 0·33) μmol/min per kg body weight:P< 0·001, ANOVA), but the response to adrenaline was unaffected by fasting. The percentage values for basal plasma palmitate turnover oxidized were 44 (SE 2; 12 h), 46 (SE 5; 36 h) and 42 (SE 4)% (72 h). In response to adrenaline this percentage fell, suggesting that adrenaline infusion may favour intra-tissue lipid oxidation.
The effect of high-molecular-weight guar gum on net apparent glucose absorption and net apparent insulin and gastric inhibitory polypeptide production in the growing pig: relationship to rheological changes in jejunal digesta
Authors: Ellis P. R. , Roberts F. G. , Low A. G. , Morgan L. M.
Published: June 2005

The present study was designed to determine the quantitative effects of starchy meals containing guar gum on rates of net apparent glucose absorption and net apparent insulin and gastric inhibitory polypeptide (GIP) production in growing pigs. The effects of these meals on the viscosity of jejunal digesta were also examined and correlated to changes in glucose absorption. Four growing pigs were each given either a low-fat semi-purified diet (control) or the same diet supplemented with a high-molecular-weight guar gum at concentrations in the diet of 20 or 40 g/kg. Blood samples were removed simultaneously via indwelling catheters from the mesenteric artery and the hepatic portal vein. Samples of jejunal digesta were removed via a T-piece cannula and used immediately for viscosity measurements at 39°. The ‘zero-shear’ viscosity of each sample was then calculated. Blood-flow measurements were made using an ultrasonic flow probe fitted to the hepatic portal vein. All measurements were made at intervals of 10 or 30 min during a 4 h postprandial period. Meals containing guar gum significantly increased (P < 0·05) the viscosity of jejunal digesta, an effect that was strongly dependent on the concentration of guar gum in the original diet. No significant differences in blood-flow rates were found between the control and guar-containing diets. Both concentrations of guar gum significantly reduced (P < 0·05) glucose absorption and insulin and GIP secretion rates over the 4 h postprandial period. An inverse relationship between the rate of glucose absorption and the ‘zero-shear’ viscosity of jejunal digesta was found. This study also provides direct evidence for the important role played by the entero-insular axis in modifying the glycaemic response to a meal containing guar gum.
Short-term satiating effect of the fat replacer sucrose polyester (SPE) in man
Authors: Hulshof Toine , De Graaf Cees , Weststrate Jan A.
Published: June 2005

The effects of different amounts of the non-absorbable fat replacer sucrose polyester (SPE), water, and fat added to six warm preload lunches on feelings of appetite and food intake were investigated in two studies that were replicates of each other. In the first study thirty-nine subjects consumed rice preloads; in the second study thirty-five subjects consumed macaroni preloads. The six preloads were fixed on three energy levels: 1·8, 2·7, or 3·7MJ. At 2 h after preload consumption a test-meal buffet of thirty-one products was presented. Food intake was recorded on the study day, and the day after the study day. For women no energy compensation occurred in either study. Men showed a tendency to compensate for the energy differences between the preloads. However, when the fat of the preloads was replaced by SPE, energy compensation was less than 50% and non-significant. Statistically significant energy-compensation (66 %) was found when fat was replaced by water. No macronutrient-specific compensation occurred in men or women in either study. Lower total fat and energy intakes were found with the preloads where fat was replaced by SPE compared with the preloads containing fat. The appetite ratings were in line with the energy intake values, with no differences in women, and higher appetite ratings after the lower energy preloads in men. This short-term study indicates that SPE may be a useful aid to reduce fat and energy intakes.
Dietary supplementation with carotenoids: effects on α-tocopherol levels and susceptibility of tissues to oxidative stress
Authors: Woodall Alan A. , Britton George , Jackson Malcolm J.
Published: June 2005

The ability of dietary supplementation with carotenoids to protect chick tissues against oxidative stress in vitro was examined. Male Leghorn chicks were fed on diets supplemented (100 mg supplement/kg diet) with either β-carotene, zeaxanthin (β,β-carotene-3,3'-diol), canthaxanthin (β,β-carotene-4,4'-dione) or α-tocopherol, or on a control diet, from 1 d old until 37 d of age. Tissues (liver, heart, skeletal muscle and plasma) were removed and assayed for total carotenoids and α-tocopherol content and portions subjected to oxidative stress by incubation of homogenates with cumene hydroperoxide and FeSO4. Animals receiving zeaxanthin and canthaxanthin had significantly greater carotenoid concentrations in liver, heart, muscle and plasma compared with untreated controls (P < 0·05); animals fed on diets supplemented with β-carotene or α-tocopherol did not have significantly different tissue carotenoid contents compared with untreated controls. α-Tocopherol supplementation elevated α-tocopherol levels in all tissues examined (P < 0·05). Supplementation with caroteuoids did not affect tissue α-tocopherol levels, but β-carotene lowered plasma α-tocopherol levels by 50% (P < 0·05). Incubation of plasma or tissue homogenates with oxidant stressors induced lipid peroxidation (production of thiobarbituric-acid reactive substances) in all tissues. Animals given α-tocopherol, β-carotene or zeaxanthin had a reduced susceptibility to oxidant stress in liver compared with unsupplemented controls (P < 0·05), and α-tocopherol-supplemented animals had reduced susceptibility in skeletal muscle compared with unsupplemented controls (P < 0·05). Canthaxanthin supplementation did not influence the susceptibility to oxidant stress in any tissue examined. These results suggest that zeaxanthin, a carotenoid present in animal and human diets, may have significant activity as an antioxidant against oxidative stress in tissues.
Multi-frequency bioelectric impedance measurements for predicting body water compartments in patients with non-ascitic liver cirrhosis
Authors: Borghil A. , Bedogni G. , Rocchi E. , Severi S. , Farina F. , Battistini N.
Published: June 2005

We assessed total body water (TBW) and extracellular water (ECW) in thirty-four non-ascitic cirrhotics and twenty healthy controls by 2H2O and Br dilution. In the same subjects, bioelectric impedance (BI) was recorded at multiple frequencies. Body hydration was similar for controls (mean 55·6 (SD 6·7)), less-severe cirrhotics (Child-Pugh classification A; CPA; n 21, mean 56·2 (SD 6·2)) and moderately-severe cirrhotics (Child-Pugh classification B; CPB; n 13, mean 57·2 (SD 5·4)). However, intracellular water standardized per litre TBW was significantly higher in CPB subjects (mean 27·0 (SD 7·5); P<0·01) compared with CPA (mean 21·3 (SD 10·6)) and control subjects (mean 18·0 (SD 9·8)). Published formulas for predicting TBW and ECW from BI at multiple frequencies were applied to the cirrhotics. These formulas gave accurate predictions of TBW and ECW, although standard errors of estimates were higher for CPB subjects (TBW ≤ 2·5 and ECW ≤ 2·11) than those for CPA (TBW ≤ 2·0 and ECW ≤ 1·81) and control (TBW 1·4 and ECW 0·9 1) subjects
Hypolipidaemic, gastrointestinal and related responses of broiler chickens to chitosans of different viscosity
Authors: Razdan A. , Pettersson D.
Published: June 2005

Broiler chickens (1-d-old) were fed ad libitum on a control diet based on maize and maize starch or diets containing low-, medium- or high-viscosity chitosans at an inclusion level of 15 g/kg. Body weights and feed intakes of chickens given chitosan-containing diets were generally depressed in comparison with those of control-fed animals on days 11 and 18 of the experiment. On days 12 and 19, feeding the low-viscosity-chitosan diet reduced plasma triacylglycerol and total plasma cholesterol concentrations in relation to chickens receiving the control diet, while the medium- and high-viscosity-chitosan-containing diets reduced total plasma cholesterol and elevated, although not significantly, plasma HDL-cholesterol concentrations compared with those of control-fed animals. Chitosan feeding generally improved plasma HDL-cholesterol: total cholesterol ratio in comparison with control feeding, which was attributed to the general reductions in plasma cholesterol concentrations rather than increases in plasma HDL-cholesterol concentrations. Feeding the high-viscosity-chitosan-containing diet significantly reduced the ileal digestibility of crude protein (N x 6·25) and crude fat compared with chickens given the control diet. The reduction in ileal crude fat digestibility was greatest among chickens receiving the high-viscosity-chitosan-containing diet and chitosan-containing diets reduced ileal fat digestibility by 8% on average compared with that of control-fed birds. However, increasing the viscosity of the chitosan fraction could not be correlated with increases in terminal ileal digesta viscosity and, therefore, it could not be established that increased ileal lumen viscosity alone contributed to reductions in body weight, feed intake and plasma cholesterol concentrations. However, the fact that ileal digestibility of fat was reduced by feeding chitosan to chickens suggests the action of other hypolipidaemic mechanisms
Apparent ileal dry matter and crude protein digestibility of rations fed to pigs and determined with the use of chromic oxide (Cr2O3) and acid-insoluble ash as digestive markers
Authors: Van Leeuwen P. , Veldman A. , Boisen S. , Deuring K. , Van Kempen G. J. M. , Derksen G. B. , Verstegen M. W. A. , Schaafsma G.
Published: June 2005

Two experiments were conducted to determine apparent ileal DM and crude-protein (CP) digesibilities in rations fed to pigs. An evaluation was made of Cr2O3 and HCl-insoluble ash as digestive markers. In addition, the effects of body weight (BW) on apparent ileal DM and CP (N x 6.25) digestibilities were studied. In Expt 1, thirteen barrows averaging 35 kg BW were fitted with post-valve T-caecum (PVTC) cannulas to determine the apparent ileal DM and CP digestibilities of a wheat gluten-bran ration (B2) and a soyabean-meal ration (E1). Immediately after morning feeding ileal digesta samples were collected on an hourly basis for a total of 12 h. Subsequently, N and marker contents were determined in the samples. The postprandial patterns of N and Cr passage were more similar than those of N and HCl-insoluble ash. Therefore Cr2O3 is more suitable as a marker than HCl-insolube ash. The apparent ileal CP digestibility coefficient of ration B2 derived using Cr2O3 as a marker was significantly (P > 0.05) higher by 0.018 compared with the value obtained using HCl-insoluble ash. The corresponding values for ration E2 obtained using Cr2O3 and HCl-insoluble ash were both 0.825. In Expt 2, apparent ileal DM and CP digestibilities were determined in eighteen rations using twelve barrows also fitted with PVTC cannulas (BW from 40 to 100 kg). The protein sources for these rations were from different groups of feedstuffs. In four and three of the rations apparent ileal DM and CP digestibilities respectively were significantly different (P < 0.05) when assessed using the two markers. The digestibility coefficients were not systematically higher or lower for either marker. Absolute differences were < 0.049 on average. Significant effects of live weight on apparent ileal CP digestibilities were found.
Nutrition in pregnant or lactating rats programs lipid metabolism in the offspring
Authors: Lucas A. , Baker B. A. , Desai M. , Hales C. N.
Published: June 2005

Epidemiological studies in humans show that size in early life is related to blood cholesterol concentrations in adult life, raising the hypothesis that early nutrition programs later lipid metabolism, affecting risk for later vascular disease. Here, we tested the hypothesis that nutrition during pregnancy or lactation in the rat programs lipid metabolism in the offspring, studied in adult life (mean 6 months). Rats (n 35) from normally-fed dams (controls) were compared with (1) rats (n 22) from dams protein-restricted in pregnancy and lactation; (2) rats (n 9) born to normally-fed mothers crossed to protein- restricted lactating dams and (3) those (n 9) born of protein-restricted dams and crossed to normally-fed lactating animals. In these latter three groups the offspring showed long-term reduction in plasma cholesterol, HDL-cholesterol and triacylglycerol concentrations compared with controls. The effects were predominantly in males. These findings suggest that in the rat the sensitive period for nutritional programming of cholesterol and triacylglycerol metabolism is both pre- and postnatal (pre-weaning) and that rats may be ‘indirectly’ programmed by altering the maternal nutritional milieu during gestation or lactation. whilst it has been hypothesized that early human undernutrition programs risk for vascular disease, one aspect of undernutrition, low maternal protein intake, in this rat model programmed lower plasma cholesterol and triacylglycerol concentrations.
The acute impact of ethanol on glucose, insulin, triacylglycerol, and free fatty acid responses and insulin sensitivity in type 2 diabetes
Authors: Christiansen Christian , Thomsen Claus , Rasmussen Ole , Hansen Carsten , Hermansen Kjeld
Published: June 2005

The aim of the present study was to evaluate the acute effect of ethanol on insulin sensitivity, and glucose, insulin, free fatty acid (FFA), and triacylglycerol responses in ten patients with non-insulin-dependent (type 2) diabetes. In the test study an oral dose of 0·66 g ethanol/kg followed by continuous intravenous infusion of 0·1 g ethanol/kg per h was given to maintain a constant ethanol level in the blood. In the control study identical volumes of oral water and intravenous saline (9 g NaCl/l) were given. After 90 min insulin sensitivity was determined by the hyperinsulinaemic, euglycaemic clamp technique. Ethanol caused no change in blood glucose or insulin concentrations. The FFA level was suppressed by ethanol while the triacylglycerol level was unaffected. The insulin sensitivity was not affected by ethanol. No major acute effect of ethanol on the glycaemic control in fasting type 2 diabetic patients was found in comparison with what is seen in healthy people. The present study, along with the sparse literature, indicates that the ability of ethanol to induce hypoglycaemia is attenuated or absent in diet-treated type 2 diabetes. Furthermore, we found no change in insulin sensitivity. Consequently, the risk of acute ethanol-induced aberrations in carbohydrate metabolism in diet-treated type 2 diabetes seems to be less than previously expected, when alcohol is not taken as a part of a meal.
Increases in calcium absorption with ingestion of soluble dietary fibre, guar-gum hydrolysate, depend on the caecum in partially nephrectomized and normal rats
Authors: Hara Hiroshi , Nagata Masashi , Ohta Atsutane , Kasai Takanori
Published: June 2005

Effects of feeding soluble dietary fibre on apparent Ca absorption and the contribution of the caecum to Ca absorption were examined in five-sixths nephrectomized (NPX)and normal rats with or without caecectomy in four experiments. It is known that Ca absorption is lowered by renal failure. In the first experiment the amounts of femur Ca increased linearly with increasing dietary Ca up to 3·0 g Ca/kg diet in intact rats. Partial nephrectomy decreased apparent Ca absorption in rats fed on diets containing 30 and 4·5 g Ca/kg diet. In the NPX groups, Ca absorption in rats fed on the diet containing guar-gum hydrolysate (GGH; 50 g/kg diet; 3·0 g Ca/kg diet) was significantly higher than that in rats fed on a fibre-free diet, and the increase in Ca absorption with GGH feeding was completely abolished by caecectomy. Also, ingestion of GGH increased Ca absorption in normal rats, but not in normal, caecectomized rats. Mg absorption was also increased with GGH feeding and was decreased with caecaectomyin NPX and normal rats. In experiments which used caecectomized rats, coprophagy wasprevented with an anal cup to avoid re-ingestion of faecal Ca. We conclude that ingestion of the soluble dietary fibre, GGH, increased apparent Ca absorption in NPX and non-NPX rats, and the caecum was responsible for these increases in Ca absorption.
Olive oil and rapeseed oil differ in their effect on plasma low-density lipoprotein metabolism in the guinea-pig
Authors: Fernandez Maria Luz , Soscia Anthony E. , Sun Gwo-Shing , Tosca Mark , McNamara Donald J. , McDonald Bruce E.
Published: June 2005

The effects of olive oil and rapeseed oil, two different high-o1eic-acid oils, on plasma LDL and hepatic cholesterol metabolism were compared in guinea-pigs. Animals were fed on semipurified diet containing 150 g fat/kg as either olive oil (OL), rapeseed oil plus 100 g palm oil/kg (C-P) or olive oil plus 350 g safflowerseed oil/kg (OL-S). Olive oil was enriched with safllowerseed oil (OL-S diet) to increase linoleic acid and to decrease palmitic acid concentrations, in order to evaluate whether differences in plasma LDL concentrations were due to intrinsic effects of the specific oil (rapeseed or olive oil) or to differences in the content of specific fatty acids. No differences due to dietary fat source were found in plasma total and HDL-cholesterol levels or in LDL composition. Plasma LDL-cholesterol levels were lower on the C-P diet than the OL diet (P< 0·05) while plasma LDL-cholesterol levels in animals fed on the OL-S diet were not significantly different from either dietary group (P> 0·05). The number of hepatic apo B/E (LDL) receptors was on average 25% higher in animals fed on the C-P diet compared with those fed on diets containing olive oil. Likewise, cardiac muscle lipoprotein lipase (EC3.1.1.34) activity was significantly higher in the C-P group than in the OL and OL-S dietary groups. Dietary fat source had no effect on hepatic cholesterol levels or 3-hydroxy-3-methylglutaryl (HMG) CoA reductase (EC1.1.1.34) activity. The results indicate that olive oil and rapeseed oil, both rich sources of monoumaturated fatty acids, differ in their effect on LDL metabolism in the guinea-pig.
Effects of varying content of soluble dietary fibre from wheat flour and oat milling fractions on gastric emptying in pigs
Authors: Johansen Helle N , Knudsen K. E.Bach , Sandström Brittmarie , Skjøth F.
Published: June 2005

Four pigs fitted with a gastric cannula were fed on a wheat-flour-based diet (WF) and three oat-based diets, consisting mainly of oat flour (OF), rolled oats (RO) or oat bran (OB), for 1 week each. The stomach contents were collected quantitatively daily at 0·5, 1, 2, 3 or 5 h after feeding. The viscosity (mPa. s) of the liquid fraction of stomach contents 1 h after feeding was 1·7 with diet WF, 15 with diet OF, 30 with diet RO and approximately 400 with diet OB. The viscosity and the concentration of β-glucan in the liquid phase was to some extent determined by the dietary level of β-glucan in the diet. However, there was a trend towards a lower viscosity after longer exposure to the gastric juices. The correlation between logarithmic values for viscosity and concentration of β-glucan in the liquid phase of digesta was r 0·45. On centrifugation of digesta there was a higher proportion present in the sediment phase when the pigs were fed on diets with a higher content of soluble dietary fibre (DF), suggesting that the digesta was more coherent. This possibility was supported by the higher water-holding capacity (WHC) of the sediment. Feeding diets with oats containing a higher soluble DF content led to lower recoveries of digesta, PEG 4000 (liquid-phase marker), and the DF components β-glucan and arabinoxylan in the first hour after feeding. No effect related to the DF content of the diet was seen in the gastric emptying of starch and Cr2O3(solid-phase marker). In conclusion, soluble DF from oatsincreased the viscosity of stomach contents and increased the ability of the dry matter to retain water. Higher levels of soluble DF led to higher recoveries of digesta, the liquid phase and DF itself in the initial stage of gastric emptying, whereas no effect was seen on the gastric emptying of starch.
The influence of dietary fibre source and level on the development of the gastrointestinal tract, digestibility and energy metabolism in broiler chickens
Authors: JøRgensen Henry , Zhao Xin-Quan , Knudsen Knud Erik Bach , Eggum Bjørn O.
Published: June 2005

The present study was undertaken to provide detailed information about the effect of fibre source (pea fibre, wheat bran or oat bran) at inclusion levels of 0, 187 and 375 g/kg diet on the development of the digestive tract, nutrient digestibility and energy and protein metabolism in broiler chickens. Heat production was measured using open-air-circuit respiration chambers. Diets with increasing levels of pea fibre decreased the DM in droppings and increased excreta output (2·5-fold) relative to DM intake. Adaptation to increased dietary fibre levels included increases in the size of the digestive system, with pea fibre exerting a stronger impact than wheat bran or oat bran. The length of the intestine, and particularly the length and weight of the caecum, increased with the fibre level. The digestibility of all nutrients also decreased with increasing fibre level. The decrease in the digestibility in relation to NSP for the three fibre sources was bigger for oat bran (0·0020 per g dietary NSP) than for pea fibre and wheat bran (0·0014 and 0·0016 per g dietary NSP) indicating that the cell walls in oat bran (aleurone and subaleurone) had a significant negative effect on the digestibility of cellular nutrients, i.e. protein and fat. The degradation of the NSP constituents was far lower in chickens than found in other animal species such as pigs and rats, thus supporting the view that chickens do not ferment fibre polymers to a great extent. Excretion of organic acids (mainly lactic acid and acetic acid) accounted for up to 2% of metabolizable energy (ME) intake with the highest excretion for the high-fibre diets. H2excretion was related to the amount of NSP degraded and indicated higher microbial fermentation with increasing fibre levels. The chickens' feed intake responded to a great extent to dietary ME concentration but expressed in terms of metabolic body size (W0·75) ME intake was depressed at the high fibre levels. Dietary NSP was able to explain between 86% (oat bran) and 96% (pea fibre) of the variation in ME concentration. The amount of energy available from fermentation of NSP appears to reach a maximum of 42 KJ/d independent of fibre source and level. Expressed in relation to ME intake the NSP fermentation contributed 3-4%. With increasing fibre intake the partitioning of retained energy between body protein and body fat changed in favour of protein.
Effects of the type and level of dietary fibre supplements on nitrogen retention and excretion patterns
Authors: Tetens Inge , Livesey G. , Eggum B. O.
Published: June 2005

abstract:

The hypothesls was tested that fermentable dietary fibre (DF) sources elevate faecal N excretion at the expense of urinary N without affecting N retention. DF that substantially increase fermentation (pectin, Sugarbeet and soya bran) or are poorly fermented (crystalline cellulose and maize bran) were fed as supplements to a basal DF-free diet a t three dose levels: 0,50 and 100 g supplement/kg basal diet. The diets were fed to juvenile male Wistar rats for 2 weeks before a 7 d period when faeces and urine were collected. Faecal excretion of N was significantly increased, dose-dependently, by all DF supplements and was positively correlated to faecal bulking. Urinary excretion of N was lower at the high doses of the DF supplements but reached significance only with the highly fermentable (0·68) sugarbeet- supplementeddiets. Regression analysis showed that the major part (0·75) of the increase in faecal N excretion due to DF supplementation was balanced by a reduction in urinary excretion; N retention was therefore, at the dose levels used, only affected to a small extent. Only in the maize-bran-supplemented diets were the reductions in N retention significant. The shift in N excretion from urine to faeces can be explained largely by the degree of microbial fermentation in the large intestine caused by the addition of DF supplements and emphasizes the modifying role that certain DF supplements may have on the enterohepatic cycle of N. Possible implications of these findings for patients with liver or renal failure or for conditions when the intake of dietary protein is marginal are discussed.
Free amino acids in milks of human subjects, other primates and non-primates
Authors: Sarwar G. , Botting H. G. , Davis T. A. , Darling P. , Pencharz P. B.
Published: June 2005

Preterm and term transitional milks of human subjects and mature milks of human subjects, non-human primates and non-primates were analysed for free amino acids (AA) using precolumn phenylisothiocyanate derivatization and liquid chromatography. Differences in free AA between three types of human milk were small. Milks of pinnipeds (seals and sea lions) contained the highest levels of total free AA (8634–20 862 μmol/1), while the milks of cows and sheep had the lowest levels of total free AA (1061–1357 μmol/1). The milks of human subjects, chimpanzees (Pan troglodytes), gorillas (Gorilla gorilla), elephants (Elephas maximus), horses and pigs had intermediate levels of total free AA (3069–7381 μmol/1). Glutamic acid was the most abundant free AA in milks of human subjects (1339–2157 μmol/1), non-human primates (423–2528 μmol/1), elephants (1332 μmol/1), horses (1119 μmol/1), and cows (349 μmol/1). Taurine was the most abundant free AA in milks of pinnipeds (5776–13 643 μmol/1), pigs (1238 μmol/1), goats (1150 μmol/1) and sheep (341 μmol/1). Taurine was the second most abundant free AA in milks of human subjects and non-human primates, while histidine was the second most abundant free AA in milks of pinnipeds. Milks of each species had a distinctive free AA pattern which may reflect the relative importance of the free AA during early postnatal development.
Enzyme activities of rumen particles and feed samples incubatedin situwith differing types of cloth
Authors: Huhtanen Pekka , Vanhatalo Aila , Varvikko Tuomo
Published: June 2005

Three ruminally cannulated non-lactating dairy cows were used to investigate the effects of six different bag cloth types with pore size (μm): free surface area (%) ratios of 200: 45, 41: 33, 16: 5, 10: 2, 6: 5 and 1: 2 respectively on the disappearance of grass silage DM and neutral-detergent fibre (NDF), and on particle-associated carboxymethylcellulase (EC3.2.1.4; CMCase) and xylanase (EC3.2.1.8) activties extracted from feed residues. Another objective was to compare microbial activity inside the bags and in rumen ingesta. Rumen incubation periods were 3, 6, 12, 24, 48 and 96 h. DM and NDF disappearance and particle-associated enzyme activities were greatly reduced with the smaller pore size and/or open surface area. Re-analysing some of the data as a 2 x 2 factorial (pore size x free surface area) indicated that, generally, free surface area rather than pore size affected the disappearance of feed components and particle-associated enzyme activities. Enzyme activities were highly correlated with NDF disappearance at 6–48 h of incubation. Cumulative area under CMCase and xylanase activity curves explained 0·79 and 0·88 of the variation in NDF disappearance when different cloth type and 6–48 h incubation data were combined. Weighted mean enzyme activities inside the bags were less than 0·35 those in rumen ingesta. The highest activity values inside the bags (24 or 48 h) were less than 0·50 those found in rumen ingesta. The lower microbial activity inside the bags explains the slower rates of NDF digestion reported within situtechniques than with rumen evacuation techniques. The general assumption of similar microbial activity inside the bags and in rumen ingesta is not justified by the present results, and caution must be taken in interpretingin situresults quantitatively for feed evaluation systems.