bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between tissue mobilization and storage in the rat
Authors: Henry Christiani Jeyakumar , Payne Philip R , Ghusain-Choueiri Amal
Published: September 2005

The amount of energy mobilized or stored as protein, expressed as a proportion of the total energy stored or mobilized (defined as the P ratio, Payne & Dugdale, 1977), was investigated in the young male (rapid growth) and adult female (slow growth) rat. Energy mobilization was induced by a 3 d fast and the changes in body content of fat and lean tissues were used to estimate the fasting P ratio (Pfast). Tissue storage was subsequently effected by 17 d of refeeding and the corresponding ratio (Prefed) was calculated from the amounts of lean and fat tissue regained. The same experimental protocol was used for measuring Pfast and Prefed in weanling (30d) and adult (130d) rats. Weight-matched individuals were assigned to three groups. All animals in group 1 were killed at the beginning of the experiment. Animals in group 2 were fasted for 3d and then killed. Group 3 animals were first fasted for 3d, then had free access to a stock diet for a further 17 d before being killed. During fasting, a close linear relationship was found between weight change and body energy changes (r 0·985, and r 0·92, P < 0·001 for weanlings and adult rats respectively) and between carcass N loss and urinary N loss (r 0·933, P < 0·001). These relationships were used to estimate the body energy and N content of each animal at the end of the initial fasting period. Hence, both Pfast and Prefed values could be calculated for all individuals at both ages. When Pfast and Prefed were calculated for adult rats, the mean values were similar (0·138 (SE 0·002) and 0·130 (SE 0·006) respectively). Individually, the Pfast, and Prefed values were correlated (r 0·54, P = 0·058). In weanling rats, the mean Prefed value was about 2·5 times the Pfast (0·421 (SE 0·0113) v. 0·156 (SE 0·004)). Despite the differences in Pfast and Prefed, the individual values were again correlated (r 0·668, P < 0·05). These results support the suggestion made by Payne & Dugdale (1977), that particular P- ratio values are characteristic of individuals and describe the extent to which protein is mobilized or stored during fasting or refeeding. These observations are discussed in relation to the predictions made by the Payne-Dugdale model.
Kinetics of dodecanedioic acid and effect of its administration on glucose kinetics in rats
Authors: Bertuzzi Alessandro , Mingrone Geltrude , Gaetano Andrea De , Gandolfi Alberto , Greco Aldo V , Salinari Serenella
Published: September 2005

Dodecanedioic acid (C12), a saturated aliphatic dicarboxylic acid with twelve C atoms, was given as an intraperitoneal bolus to male Wistar rats, with the aim of evaluating C12 suitability as an energy substrate for parenteral nutrition. The 24 h urinary excretion of C12 was 3·9% of the administered dose. C12 kinetics were investigated by a one-compartment model with saturable tissue uptake and reversible binding to plasma albumin. The analysis of plasma concentration and urinary excretion data from different animals yielded the population means of the kinetic parameters: renal clearance was 0·72ml/min per kg body weight (BW) (much smaller than inulin clearance in the rat), and maximal tissue uptake was 17·8 μmol/min per kg BW corresponding to 123·7 J/min per kg BW. These results encourage the consideration of C12 as a possible substrate for parenteral nutrition. To investigate the effect of C12 administration on glucose kinetics, two other groups of rats, one treated with an intraperitoneal bolus of C12 and the other with saline, were subsequently given an intravenous injection of D-[U-14C]glucose in a tracer amount. Radioactivity data of both control and C12-treated rats were analysed by means of a two-compartment kinetic model which takes into account glucose recycling. The estimates of glucose pool size (2·3 mmol/kg BW) and total-body rate of disappearance (82·1 μmol/min per kg BW) in control rats agreed with published values. In C12-treated rats, the rate of disappearance appeared to be reduced to 36·7 μmol/min per kg BW and the extent of recycling appeared to be negligible.
Synthesis and intravenous infusion into the rat of glyceryl bisacetoacetate, 1-acetoacetamido-2, 3-propane diol, and partially reduced glucosyl pentaacetoacetate
Authors: Birkhahn Ronald H , Clemens Robert J , Hubbs John C
Published: September 2005

The efficacy of parenteral nutrition could be improved by finding a more effective energy source. Esters of short-chain fatty acids have exhibited some promise as alternatives to glucose. The present study reports on two new esters and one amide, each containing acetoacetate as the organic acid. The three compounds: glyceryl bisacetoacetate, N-2',3'-dihydroxypropyl-3-oxo-butanamide (1-acetoacetamido-2,3-propane diol), and partially reduced glucosyl pentaacetoacetate, were synthesized and then continuously infused into rats for 7d. The infusion rate provided 50% of the rats' estimated metabolic energy requirement, and rats were fed with a reduced-energy oral diet that provided the remaining 50% of energy plus adequate protein. Rat groups for each compound were: (1) experimental-compound-infused and ad libitum-fed, (2) isoenergetic glucose-infused and pairfed, and (3) saline infused and pair-fed. Body-weight changes, N losses and N retention were measured daily. All rats died from partially reduced glucosyl pentaacetoacetate infusion at 100% and 50% of the intended rate. Rats infused with l-acetoacetamido-2,3-propane diol failed to gain weight and to increase the plasma ketone-body concentration. Glyceryl bisacetoacetate produced hyperketonaemia, and weight gain and N variables that were similar to those for glucose-infused rats. It was concluded that only glyceryl bisacetoacetate would make a satisfactory parenteral nutrient.
Fish oils and human diet
Authors: Sargent J.R.
Published: September 2005

Trends in global fish catches are described together with fish landlings and fish consumption in the UK. The importance of n–6 and n–3 polyunsaturated fatty acids as essential constituents of human diets is considered and the role of oily fish as a dietary source of the long-chain n–3 polyunsaturates, docosahexaenoic acid and eicosapentaenoic acid, is emphasized. The origin ofn–3 polyunsaturates in the marine phytoplankton and their transmission via zooplankton to fish is described as a means of understanding the consumption of different fish body oils. The ease with which the fatty acid composition of fish body oils can be manipulated by altering the fatty acid composition of their feeds is emphasized and the dietary requirements of marine and freshwater fish for n–3 and n–6 polyunsaturates considered. Farming fish on diets containing principally fish meal and fish oil, as used in salmon production in Scotland, generates a high quality product with levels of long-chain n–3 polyunsaturates equalling or exceeding those of wild fish. Farming fish on high quality marine oils rich in docosahexaenoic and eicosapentaenoic acids is an efficient means of delivering these essential nutrients in human diets and also efficiently exploiting a strictly limited marine bioresource.
Nutritional factors affecting the fatty acid composition of bovine milk
Authors: Mansbridge R. J. , Blake J. S.
Published: September 2005

The predominant fatty acids in milk are the long-chain fatty acids myristic, palmitic and stearic. These saturated fatty acids account for 75 % of the total fatty acids, with a further 21 % occurring as monounsaturated fatty acids of which the most prevalent is oleic acid. Only 4 g/lOO g of the milk fatty acids are polyunsaturated, occurring mainly as linoleic and linolenic acids. All milk fatty acids are derived, almost equally, from either de novo synthesis or directly from preformed fatty acids in the diet. There are four main dietary sources of fatty acids: forages, oilseeds, fish oil and fat supplements. The digestive tract exerts a profound influence on the fate of dietary fatty acids. The short-chain saturated free fatty acids are absorbed through the walls of the rumen or abomasum into the bloodstream. The medium- and longer-chain saturated fatty acids pass into the small intestine, diffuse across the membrane wall where they are incorporated into lipoproteins and enter the bloodstream via the lymphatic system. The majority of unsaturated fatty acids are extensively hydrogenated in the rumen. However, recent work has shown that the levels of certain saturated fatty acids can be reduced and the levels of oleic, linoleic and linolenic fatty acids increased by feeding oilseeds rich in mono- or polyunsaturated fatty acids. In addition, work reported here has confirmed that eicosapentaenoic and docosahexaenoic acids can be transferred to milk when a diet containing fish oil is fed, but the transfer efficiencies are low
Comparison ofn–3 fatty acid sources in laying hen rations for improvement of whole egg nutritional quality: a review
Authors: Van Elswyk Mary E.
Published: September 2005

The nutritional manipulation of the diets of laying hens to include sources ofn–3 fatty acids promotes the deposition of these nutrients into egg yolk.n–3 Fatty acid-rich eggs may provide an exciting alternative food source for enhancing consumer intake of these proposed healthful fatty acids. Care must be taken when designingn–3 fatty acid-rich poultry rations, however, to assure that the resulting egg fatty acid profile is useful for promoting consumer health yet maintaining egg sensory quality. In study 1 laying hens were fed on diets supplemented with graded levels of menhaden oil (MO), rich in both eicosapentaenoic acid (EPA; 20:5n–3) and docosahexaenoic acid (DHA; 22: 6n–3), for 4 weeks to determine maximal yolk fatty acid deposition attainable without sensory compromise. Yolk fatty acids were analysed for an additional 4 weeks, post-MO removal, to investigate yolkn–3 fatty acid tenacity. Dietary MO levels between 15 and 30g/kg yielded the greatest yolkn–3 fatty acid content; however, only eggs from birds fed with 15g MO/kg were considered acceptable by trained flavour panelists. Evaluation of eggs from hens fed with 15g MO/kg during storage verified that the shelf-life of enriched eggs was comparable with that of typical eggs. In study 2, graded levels of whole or ground flaxseed were used for the deposition of linolenic acid (LNA; 18:3n–3) and to determinein vivoproduction of DHA from dietary LNA for yolk deposition. Flaxseed form influenced yolkn–3 fatty acids only when given at 150 g/kg diet. In vivo production of DHA, while significant, was not enhanced by increasing the level of dietary flaxseed nor by grinding the seed. In the third study, a DHA-rich natural marine alga (MA) was investigated as ann–3 fatty acid supplement. Despite similar DHA profiles, dietary MA was found to be more efficient for yolk DHA deposition than dietary MO. These studies suggest that there are numerous viablen–3 fatty acid supplements for poultry rations. It must be realized, however, that the fatty acid profile of the final product varies substantially depending on which supplement is fed.
Longitudinal dietary changes between 1984–5 and 1991–2 in British adults: associations with socio-demographic, lifestyle and health factors
Authors: Prevost A. Toby , Whichelow Margaret J. , Cox Brian D.
Published: September 2005

The study aimed to examine dietary changes and their associations with demographic, lifestyle and health variables in a random sample of British adults. TheHealth and Lifestyle Surveyof 1984–5 (HALS1) identified four main dietary components by principal component analysis from food frequency data. Comparison of the HALS1 dietary component scores with those of the follow-up survey of 1991–2 (HALS2) for the same individuals revealed increases on component 1 (high weightings for fresh fruit, salads, ‘brown’ bread, fruit juice and green vegetables but low weightings for chips, fried food and processed meat). There were substantial decreases on component 2 (high weightings for puddings/pies, cake, potatoes, biscuits, preserves, pulses and meat), small increases on component 3 (high weightings for crisps, soft drinks and chips) and increases on component 4 (high weightings for confectionery, biscuits and cake and low weightings for vegetables of all kinds). Except for women on component 3 the changes were all significant,P< 0·001. Unadjusted score changes were smallest in elderly respondents for all components. Differences in score changes between groups were based on an analysis of covariance adjusting for the HALS1 score. On component 1 the largest score increases were associated with non-manual groups, improvements in lifestyle and good health. For component 2 the greatest changes in score were associated with changes in household size, smoking habit and heavy drinking. Score increases on component 3 were also associated with heavy drinking, whilst the largest rises on component 4 were amongst the non-manual, the non-drinkers and the non-smokers and, for women only, those who had few malaise symptoms or who lived in Scotland. The results show that there have been overall dietary changes and that changes have been associated with longitudinal alterations in socio-demographic, lifestyle and health circumstances.
Feasibility of heart-rate monitoring to estimate total level and pattern of energy expenditure in a population-based epidemiological study: the Ely young cohort feasibility study 1994–5
Authors: Wareham Nicholas J. , Hennings Susie J. , Prentice Andrew M. , Day Nicholas E.
Published: September 2005

Increasing the precision of measurements of total energy expenditure in population-based epidemiological studies is important for accurately quantifying the relationship between this exposure and disease. Current questionnaire-based methods cannot accurately quantify total energy expenditure, although they may provide an estimate of the frequency of vigorous activities. Heart rate monitoring with individual calibration has been advocated as a method for assessing energy expenditure in field studies and has been compared with the ‘gold standard’ techniques of doubly-labelled water and indirect calorimetry. However the method has previously only been used on small and selected populations. This study was, therefore, established to test the feasibility of using heart rate monitoring in a population-based study of adults. A total of 167 individuals aged 30–40 years were randomly selected and underwent 4 d heart-rate monitoring. Only three individuals could not complete the protocol. The mean physical activity level (PAL) measured over 4 d was 1.89 (sd 0.40) in men and 1.76 (sd 0.31) in women. There was no difference between mean PAL on weekend days compared with weekdays (mean paired difference 0.0008, 95% CI −0.06 to + 0.06). The estimate of mean PAL was not correlated with BMI, percentage body fat or the waist:hip ratio. It was, however, correlated with cardio-respiratory fitness as measured by VO2max per kg (Spearman rank correlation coefficient 0.50 in men and 0.42 in women). The pattern of energy expenditure was assessed by calculating the percentage of daytime hours in which PAL was greater than five times basal energy expenditure. This measure was strongly correlated with the mean PAL in both men (Spearman correlation coefficient 0.77) and women (0.71). We conclude that heart-rate monitoring is a feasible method for assessing the pattern and total level of energy expenditure in medium-sized epidemiological studies. It may also prove useful as the reference technique for calibrating questionnaires to estimate energy expenditure in larger scale studies.
Glucose and ]13C[leucine metabolism by the portal-drained viscera of sheep fed on dried grass with acute intravenous and intraduodenal infusions of glucose
Authors: Cappelli F. Piccioli , Seal C. J. , Parker D. S.
Published: September 2005

The effect of exogenous glucose supply by either intrajugular (IJG) or intraduodenal (IDG) infusion at 2.0 mg glucose/kg body weight per min was investigated in four wether sheep (average weight 44 (sd 4) kg) chronically catheterized in the carotid artery and portal veins. Sheep were fed on a dried grass pellet diet hourly using continuous belt feeders. Whole-body glucose irreversible loss (IL) rate, measured with [6-3H[glucose, was increased by 0.5 and 0.8 of exogenous supply for IJG and IDG infusions respectively. Portal glucose utilization, measured by isotope dilution across the portal-drained viscera, was unaffected by additional glucose regardless of the route of glucose supply (P= 0.76 for control ν. glucose infusions) and was a constant proportion of glucose IL (0.28) for all treatments. Portal plasma flow was higher during IDG infusions compared with IJG infusions (1.65 ν. 1.44 litres/min,P=0.055). Circulating total free amino acid concentrations fell during glucose infusions (2146, 1808 and 1683 μmol/l for control, IJG and IDG treatments respectively,P=0.067 for treatment effect) but net portal absorption was not affected by increased glucose supply. Recovery in the portal vein of [1-13C[leucine infused into the duodenum averaged 0.65 and was not affected by increasing glucose supply to the gut tissues. The results show that glucose utilization by gut tissues is responsive to changes in both vascular and luminal glucose supply. The effects of changing gut tissue use of glucose and increased whole body glucose IL on metabolism of nutrients is discussed.
A role for thyroid hormones in the regulation of diet-induced thermogenesis in birds
Authors: Gabarrou Jean-François , Duchamp Claude , Williams John , Géraert Pierre-André
Published: September 2005

The possible involvement of thyroid hormones in avian diet-induced thermogenesis (DIT) was investigated in two lines of cockerels divergently selected for high (R-) or low (R+) food efficiency. For a given body weight, R+ cockerels exhibited a higher food intake than R- cockerels (+49 to +76%) and increased DIT (+25%). Plasma thyroxine (T4) levels did not differ between lines whatever the feeding status of the birds. Plasma 3,5,3'-triiodothyronine (T3) level was lower in fasted R+ than in fasted R- cockerels while the opposite was observed after a meal. Iopanic acid injections reduced both plasma T3 concentrations and heat production to the same levels in both lines. Hepatic 5'-deiodinase activity measured with an exogenous sulfhydryl group (dithiothreitol) did not differ between lines, but when the sulfhydryl group was omitted, the activity was higher in R+ than in R- birds (90 ν. 42 pmol T3/min per liver). T3-binding capacity of isolated hepatic nuclei was higher (+76%) in R+ than in R- birds. Long-term or acute pair-feeding of R+ cockerels to the level of R- controls did not alter these results. The present results suggest that T3, mainly originating from peripheral conversion of T4 to T3, is involved in DIT in the R+ line. Availability of endogenous sulfhydryl groups appears to play an important part in the modulation of hepatic deiodinase activity. The higher concentration of nuclear T3 receptors may further increase the effects of the hormone, suggesting a major role of thyroid hormones associated with catecholamines in the stimulation of avian DIT. The underlying thermogenic mechanisms remain to be elucidated.
A model of magnesium metabolism in young sheep. Magnesium absorption and excretion
Authors: Robson A. B. , Field A. C. , Sykes A. R. , McKinnon A. E.
Published: September 2005

A model of Mg metabolism in sheep is proposed. It is based on standard Michaelis-Menten enzyme kinetics to describe the transport of Mg across the rumen wall and passive diffusion to describe the absorption of Mg in the hindgut. Factors known to have an effect on Mg metabolism in farm animals, namely the concentrations of K and Mg in the diet, and the physico-chemical conditions within the rumen as determined by the type of diet, are incorporated into the model. Consideration of the rumen as the only site of Mg absorption provided an inadequate mechanistic description of Mg metabolism in sheep. To ensure compatibility between predicted Mg absorption and recent independent data sets for Mg balances, it was necessary to include in the model aspects of Mg absorption that operate in the hindgut. The results from this model suggest that there is a need for a series of experiments to determine the important aspects of Mg transport in the hindgut of sheep. Mechanisms of homeostasis are discussed.
Rift Valley lake fish and shellfish provided brain-specific nutrition for early Homo
Authors: Broadhurst C. Leigh , Cunnane Stephen C. , Crawford Michael A.
Published: September 2005

An abundant, balanced dietary intake of long-chain polyunsaturated fatty acids is an absolute requirement for sustaining the very rapid expansion of the hominid cerebral cortex during the last one to two million years. The brain contains 600 g lipid/kg, with a long-chain polyunsaturated fatty acid profile containing approximately equal proportions of arachidonic acid and docosahexaenoic acid. Long-chain polyunsaturated fatty acid deficiency at any stage of fetal and/or infant development can result in irreversible failure to accomplish specific components of brain growth. For the past fifteen million years, the East African Rift Valley has been a unique geological environment which contains many enormous freshwater lakes. Paleoanthropological evidence clearly indicates that hominids evolved in East Africa, and that early Homo inhabited the Rift Valley lake shores. Although earlier hominid species migrated to Eurasia, modem Homo sapiens is believed to have originated in Africa between 100 and 200 thousand years ago, and subsequently migrated throughout the world. A shift in the hominid resource base towards more high-quality foods occurred approximately two million years ago; this was accompanied by an increase in relative brain size and a shift towards modem patterns of fetal and infant development. There is evidence for both meat and fish scavenging, although sophisticated tool industries and organized hunting had not yet developed. The earliest occurrences of modem H. sapiens and sophisticated tool technology are associated with aquatic resource bases. Tropical freshwater fish and shellfish have long-chain polyunsaturated lipid ratios more similar to that of the human brain than any other food source known. Consistent consumption of lacustrine foods could have provided a means of initiating and sustaining cerebral cortex growth without an attendant increase in body mass. A modest intake of fish and shellfish (6–12% total dietary energy intake) can provide more arachidonic acid and especially more docosahexaenoic acid than most diets contain today. Hence, ‘brain-specific’ nutrition had and still has significant potential to affect hominid brain evolution.
A comparison of iron absorption in adults and infants consuming identical infant formulas
Authors: Hurrell Richard F. , Davidsson Lena , Reddy Manju , Kastenmayer Peter , Cook James D.
Published: September 2005

Fe absorption was estimated in adults and infants from the erythrocyte incorporation of Fe isotopes added to infant formula. Fe absorption was measured in adults using radioisotopes, and in infants with a stable-isotope technique. In adults, the geometric mean Fe absorption from a ready-to-feed soya formula with its native phytic acid content was 2·4%. This increased to 6·0% (P< 0·05) after almost complete dephytinization. In infants, mean Fe absorption values were 3·9 and 8·7% respectively from the same products (P<0·05). In adults, mean Fe absorption from a spray-dried soya formula containing 110mg ascorbic acid/I was 4·1%, increasing to 5·3% (P< 0·05) when ascorbic acid was doubled to 220 mg/l. In infants, mean Fe absorption values were 5·7 and 9·5% (P< 0·05) from the same products. Mean Fe absorption from a milk-based formula was 6·5% in adults compared with 6·7% in infants. All meals in the adult and infant studies were fed using an identical meal size of 217g. Increasing the meal size threefold in adults did not change fractional Fe absorption. Mean Fe absorption values for each meal were lower in adults than in infants, but the relative inhibitory effect of phytic acid and the enhancing effect of ascorbic acid were similar. We conclude that Fe absorption studies in adults can be used to assess the influence of enhancers and inhibitors of Fe absorption in infant formulas fed to infants. Further studies, however, are required to extend these findings to weaning foods and complete meals.
Lignan and isoflavonoid concentrations in tea and coffee
Authors: Mazur W. M. , Wähälä K. , Rasku S. , Salakka A. , Hase T. , Adlercreutz H.
Published: September 2005

Tea is a beverage consumed widely throughout the world. The existence in tea of chemopreventing compounds possessing antimutagenic, anticarcinogenic and antioxidative properties has been reported. High intakes of tea and foods containing flavonoids have recently been shown to be negatively correlated to the occurrence of CHD. However, tea may contain other compounds with similar activities. Using a new gas chromatographic–mass spectrometric method we measured lignans and isoflavonoids in samples of twenty commercial teas (black, green and red varieties) and, for comparison, six coffees. Both unbrewed and brewed tea were investigated. The analysis of the teas yielded relatively high levels of the lignans secoisolariciresinol (5.6–28.9 mg/kg; 15.9–81.9 μmol/kg) and matairesinol (0.56–4.13 mg/kg; 1.6–11.5 μmol/kg) but only low levels of isoflavonoids. Because the plant lignans, as well as their mammalian metabolites enterolactone and enterodiol, have antioxidative properties and these mammalian lignans occur in high concentrations in plasma, we hypothesize that lignan polyphenols may contribute to the protective effect of tea on CHD.
Elevation of feed intake in parasite-infected lambs by central administration of a cholecystokinin receptor antagonist
Authors: Dynes* Robyn A. , Poppi Dennis P. , Barrell Graham K. , Sykes Andrew R.
Published: September 2005

The role of cholecystokinin (CCK) in modulating feed intake depression in parasite-infected lambs was investigated using CCK receptor antagonists (L364–718 and loxiglumide). Four experiments were carried out using ewe lambs infected with 4000 Trichostrongylus colubriformis larvae/d or non-infected controls (n 8, live weight 25 kg). Animals were fed daily on a nutritionally complete pelleted diet and had free access to water. In the first experiment, infected and non-infected animals were injected subcutaneously with CCK antagonist (100 μg L364–718) or carrier alone as a single dose. In the second experiment, CCK antagonist (loxiglumide: 0, 5, 10 or 20mg/kg live weight) was injected into a jugular vein immediately before feeding. In the third experiment, animals were infused continuously with the CCK antagonist (loxiglumide; 10mg/kg per h) for 10 min before feeding and for the first 2 h of feeding. In the final experiment, lambs were fitted with an indwelling cerebral ventricular cannula and infused with a CCK antagonist (loxiglumide, 162μg/min), CCK agonist (CCK-8, 2.5 pmol/min), loxiglumide plus CCK-8 or sterile saline solution alone via the cannula for 30 min before feeding and for the first 60 min of feeding. In all the experiments short-term feed intake was recorded at 10 and 15 min intervals for the first and second hours of feeding respectively, then at hourly intervals for the remainder of the 8 h recording period. Peripheral injection with L364–718 or loxiglumide did not elevate feed intake in either the infected or non-infected animals. However, feed intake was increased (P < 0.05) in the short term by central infusion of loxiglumide, this effect being greater in the infected animals and apparently due to an elevation in intake during the second hour of feeding. CCK-8 depressed short term feed intake only in the infected animals (P < 0.05). Total daily feed consumption was not influenced by any of the pharmacological agents. The results indicate an involvement of central CCK receptors in regulation of feed intake depression following gastrointestinal parasitism of sheep and the possibility of a similar role in non-infected sheep. They do not support the singular importance of a peripheral action of CCK in determining satiety.

Cholecystokinin: Loxiglumide: Feed intake: Gastrointestinal parasites
Conditioned flavour aversions in sheep: the relationship between the dose rate of a secondary plant compound and the acquisition and persistence of aversions
Authors: Kyriazakis I. , Anderson D. H. , Duncan A. J.
Published: September 2005

Within the overall objective of whether ruminants are able to form conditioned aversions (CFA) toward a food flavour associated with the administration of an aversive stimulus which occurs naturally in food plants (oxalic acid, OA), two specific objectives were tested: (1) whether the rate and degree of formation of CFA are dependent on the dose rate of OA administered and (2) whether the persistence of formed CFA depends on the previous dose rate of OA. Sheep were conditioned to associate the specific flavour of one of two novel foods with either the oral administration of OA or equivalent placebos. Four dose rates of OA were tested (0.06, 0.12, 0.18 and 0.24 g/kg sheep live weight per d), with twelve sheep per dose. Each conditioning period lasted for 8 d and was repeated four times. At the end of each conditioning period the preference for the two flavours was measured in short-term, 20min preference tests. The persistence of the CFA was measured at 0, 7, 21 and 49 d after the completion of the conditioning phase with long-term, 3 h preference tests. The results of the experiment indicated that: (1) the rate and degree of formation of CFA were dependent on the rate of administration of OA; (2) sheep required repeated exposures to the lower dose rates of OA in order to develop CFA and these CFA did not persist in the absence of continual reinforcement; (3) CFA to the higher dose rates of OA were developed after as little as one exposure and persisted over a period of at least 7 weeks. These findings are consistent with the expectation that ruminants should be able to select a diet which minimizes the risk of consumption of potentially harmful foods, whilst at the same time maintaining a degree of flexibility in their feeding behaviour.
Effects of soya milk and Bifidobacterium-fermented soya milk on plasma and liver lipids, and faecal steroids in hamsters fed on a cholesterol-free or cholesterol-enriched diet
Authors: Kikuchi-Hayakawa H. , Onodera N. , Matsubara S. , Yasuda E. , Shimakawa Y. , Ishikawa F.
Published: September 2005

The effects of freeze-dried soya milk (SM) and Bifidobacterium-fermented soya milk (FSM) on plasma and liver lipids, and faecal steroid excretion were estimated in hamsters fed on a cholesterol-free or cholesterol-enriched diet. Hamsters fed on the cholesterol-free diet containing 300 g FSM/kg had lower levels of plasma VLDL + LDL cholesterol than the animals fed on the control diet. SM in the diet produced a similar pattern without significant differences. In the cholesterol-enriched diet group, SM and FSM decreased the levels of plasma total cholesterol and VLDL + LDL-cholesterol. SM and FSM decreased the plasma triacylglycerol level in both the cholesterol-free and -enriched diet groups. The liver total cholesterol contents in the SM and FSM groups were lower than that in the control group, for hamsters fed on the cholesterol-free diet. The liver triacylglycerol content was not modified by SM or FSM in hamsters fed on either the cholesterol-free or -enriched diet. SM and FSM increased the total bile acid excretion and the proportion of cholesterol entering the cholic acid biosynthesis pathway in both the cholesterol-free and -enriched diet groups. SM and FSM did not affect neutral steroid excretion in the cholesterol-free or -enriched diet group. There was an inverse relationship between VLDL + LDL-cholesterol and faecal bile acid excretion in hamsters fed on the cholesterol-free (r−0.670,P< 0.01) and cholesterol-enriched (r−0.761,P< 0.001) diets respectively. These results indicated that SM had an anti-atherogenic effect, and that this effect was not diminished by prior fermentation.
Inadequate vitamin D status: does it contribute to the disorders comprising syndrome ‘X’?
Authors: Boucher B. J.
Published: September 2005

Environmental factors are important in the aetiology of glucose intolerance, type II diabetes and IHD. The lack of vitamin D, which is necessary for adequate insulin secretion, relates demographically to increased risk of myocardial infarction. These disorders are connected, degenerative vascular disease increasing with glucose intolerance and diabetes and, with its risk factors, comprising syndrome ‘X’. Evidence is presented suggesting that vitamin D deficiency may be an avoidable risk factor for syndrome ‘X’, adding another preventative measure to current recommendations which are aimed at reducing the worldwide epidemic of these disorders. Experimentally, vitamin D deficiency progressively reduces insulin secretion; glucose intolerance follows and becomes irreversible. Relationships between vitamin D status, glucose tolerance and 30 min insulin secretion during oral glucose tolerance tests are reported in British Asians; insulin secretion, but not glycaemia, improving with short-term supplementation. Studies showing reduction in blood pressure and in risk of heart attack and diabetes with exercise (usually outdoor), rarely consider the role of vitamin D status. Glycaemia and insulin secretion in elderly European men, however, relate to vitamin D status, independent of season or physical activity. Prolonged supplementation can improve glycaemia. Hypertension improves with vitamin D treatment with or without initial deficiency. Vitamin D status and climate are reviewed as risk factors for myocardial infarction; the risk reducing with altitude despite increasing cold. Glycaemia and fibrinogenaemia improve and insulin secretion increases in summer. Variation in vitamin D requirements could arise from genetic differences in vitamin D processing since bone density can vary with vitamin D-receptor genotype. Vitamin D receptors are present in islet β cells and we report insulin secretion in healthy Asians differing profoundly with the Apa I genotype, being independent of vitamin D status. Those at risk of vitamin D deficiency include the elderly, those living indoors or having a covered-up style of dress, especially dark-skinned immigrants, and pregnant women, and these are groups recognized as being at increased risk of diabetes.
Metal (molybdenum, copper) accumulation and retention in brain, pituitary and other organs of ammonium tetrathiomolybdate-treated sheep
Authors: Haywood Susan , Dincer Zuhal , Holding J. , Parry Nicola M.
Published: September 2005

Ammonium tetrathiomolybdate (TTM) is the treatment of choice for chronic Cu poisoning in sheep and is recommended in Wilson's disease. However, the long-term effects have not been fully evaluated and some evidence questions the long-term safety of the drug. The aim of the present study was to investigate the systemic distribution and retention of Cu and Mo in TTM-treated sheep of different breeds and Cu status. Low-Cu Cambridge sheep were divided into a TTM trial group (3·4 mg/kg, subcutaneously, on three alternate days per month, for 5 months) and a control group, and were killed at the end of the course or 7 months later. High-Cu sheep consisting of a Cu-supplemented (150 mg/kg) Cambridge group and a North Ronaldsay group were administered TTM as before and compared with untreated controls. Brain, liver, kidney, heart, skeletal muscle, pituitary, adrenals, testes and ovaries were retained for metal analysis. Mo accumulated in all organs including brain and pituitary (P < 0·02) in all TTM trial groups and was retained after cessation of treatment, except in liver, kidney and skeletal muscle. Cu was increased (P < 0·02) and retained in the cerebellum and medulla oblongata in the TTM-treated high-Cu Cambridge groups. Brain Cu v. Mo concentrations showed a strongly positive correlation (r 0·7) in the high-Cu Ronaldsay group 7 months after TTM treatment. It is concluded that TTM is not all excreted but (Mo) is widely distributed and retained in many organs including brain and pituitary. In addition TTM may redistribute some displaced excess liver Cu (Cu-TTM) to the brain. The consequences of these disturbances await clarification.
Maternal nutrition in early-mid gestation and placental size in sheep
Authors: Clarke Lynne , Heasman Lindsay , Juniper Darren T. , Symonds Michael E.
Published: September 2005

We investigated the influence of restricted maternal nutrition between 30 and 80 d gestation on placental growth. Singleton-bearing ewes were fed on either 0.6 (i.e. nutrient restricted) times their energy requirements or 2.25 times this amount (i.e. controls) up to 80 d gestation, when their placentas and fetuses were sampled and analysed. Nutrient-restricted ewes lost body condition score but not body weight and had lower plasma thyroid hormone concentrations than controls, but there were no differences in plasma glucose, non-esterified fatty acids or 3-hydroxybutyrate concentrations between groups. There was no effect of maternal nutrient restriction on fetal weight, conformation or organ weights with the exception of brain weight which was lower in nutrient-restricted ewes. Nutrient restriction had no effect on total placental weight, or proportion of inverted placentomes, but was associated with an increased abundance of small placentomes and decreased weight of the fetal but not maternal components of the placenta. Fetal cotyledons from nutrient-restricted ewes also had a lower DNA but higher haemoglobin concentration than those sampled from controls. The plasma concentration of triiodothyronine in umbilical cord plasma was also increased in fetuses from nutrient-restricted ewes. In conclusion, maternal nutrient restriction during early-mid gestation is associated with a smaller placenta.
Diet during pregnancy and the risk of cerebral palsy
Authors: Petridou Eleni , Koussouri Mary , Toupadaki Nektaria , Youroukos Sotiris , Papavassiliou Antigoni , Pantelakis Stephanos , Olsen Jorn , Trichopoulos Dimitrios
Published: September 2005

The role of maternal diet in the development of the fetal brain has not been adequately explored. Marine n-3 fatty acids have, however, been proposed to be important for brain development. The present case–control study aimed to investigate the relationship between dietary intake during pregnancy and the occurrence of cerebral palsy (CP) in the offspring. Children with CP (n 109), born between 1984 and 1988 to mothers residing in the Greater Athens area, were identified at any time in 1991 or 1992 through institutions delivering care and rehabilitation. Successful nutritional interviews were conducted with ninety-one of these children. Controls were chosen among the neighbours of the CP cases or were healthy siblings of children with neurological diseases other than CP, seen by the same neurologists as the children with CP. A total of 278 control children were chosen, and 246 of them were included in the nutritional study. Guardians of all children were interviewed in person on the basis of a questionnaire covering obstetric, perinatal socioeconomic and environmental variables. A validated semiquantitative food-frequency questionnaire of 111 food items was used to estimate maternal dietary intake during pregnancy. Statistical analysis was done by modelling the data through logistic regression. Food groups controlling for energy intake were alternatively and simultaneously introduced in a core model containing non-nutritional confounding variables. Consumption of cereals (mostly bread) and fish intake were inversely associated with CP (P < 0·05 and P < 0·09 respectively) whereas consumption of meat was associated with increased risk (P < 0·02). A protective effect of fish consumption and a detrimental effect of meat intake have been suggested on the basis of earlier work and appear to be biologically plausible. If corroborated by other studies, these results could contribute to our understanding of the nutritional influences on fetal brain development.
Fat balance and ageing: results from the Québec Family Study
Authors: Tremblay Angelo , Drapeau Vicky , Doucet Eric , Alméras Natalie , Després Jean-Pierre , Bouchard Claude
Published: September 2005

The aim of the present study was to evaluate changes in participation in physical activity and in fat and alcohol intake associated with ageing. This issue was examined in adults (n 207) who were tested between 1978 and 1982 and re-tested 12 years later. These adults were 42.3 (sd 4.9) years of age at baseline. Their children (n 122) were tested over the same follow-up period. They were, on average, 12.5 (sd 1.9) years at entry into the study. A decrease in the proportion of daily energy intake as fat and an increase in participation in vigorous physical activities were observed over the 12-year period in both groups. The proportion of dietary energy as alcohol remained stable in adults whereas it increased markedly in children. Correlation analyses between baseline and follow-up levels were significant for dietary fat and alcohol intake in adults. In children, the levels of these variables in the growing years did not predict the levels attained 12 years later. Even though the adults displayed changes in fat balance generally following current public health recommendations, a substantial increase in skinfold thicknesses was observed in these subjects during follow-up. This observation suggests that there is a strong effect of age-related factors on fat balance.
Ascorbic acid levels in maternal milk: differences with respect to ascorbic acid status during the third trimester of pregnancy
Authors: Ortega Rosa M. , Quintas M. Elena , Andrés Pedro , Martínez Rosa M. , López-Sobaler Ana M.
Published: September 2005

The aim of the present investigation was to study the relationship between ascorbic acid status during the third trimester of pregnancy and levels of this vitamin in transition milk (days 13–14 of lactation) and mature milk (day 40 of lactation). To this end, the pregnancies and lactation periods of fifty-seven healthy women between 18 and 35 years of age (27 (sd3.7) years) were monitored. Vitamin intake during the third trimester was determined by recording the consumption of foods over 5 d, and by registering the quantities provided by dietary supplements. Ascorbic acid levels in maternal serum during this stage of pregnancy, and in transition and mature milk samples, were determined by spectrophotometry. Those subjects with ascorbic acid intakes below that recommended (80 mg/d) (group L) showed lower consumption of fruit and vegetables than did those with greater intakes (group H). The consumption of ascorbic acid supplements was very low, and was only seen in three group H subjects. The difference in ascorbic acid intake was reflected at serum level. Group L subjects showed significantly lower serum values than did group H subjects (30.1 (sd36.3) μmol/l compared with 101.1 (sd168.1) μmol/l). Vitamin intake also influenced the composition of transition milk. Group L subjects showed significantly lower levels of ascorbic acid in milk than did group H subjects (255.5 (sd220.3) μmol/l compared with 437.8 (sd288.4) μmol/l). The results of the present study reveal the need to increase the consumption of fruits and vegetables during pregnancy and to monitor maternal ascorbic acid intake and vitamin C status.
Nutritional status of hospitalized acute stroke patients
Authors: Gariballa Salah E. , Parker Stuart G. , Taub Nick , Castleden Mark
Published: September 2005

The nutritional status of 201 hospitalized stroke patients was assessed from anthropometric, haematological and biochemical data in an observational prospective study. On admission, sixty-two (31%) stroke patients had BMI < 20, ninety-nine (49%) had a triceps skinfolds thickness below the 25th centile, twenty-five (12%) had a mid-arm circumference below the 25th centile and thirty-eight (19%) had a serum albumin concentration below 35 g/1. Baseline nutritional status was worse among those who later died or remained in hospital compared with those discharged and most patients who remained in hospital showed marked and significant deterioration in all measures of nutritional status within 4 weeks of hospitalization. After adjusting for age, stroke severity and co-morbidity, low serum albumin concentrations of these patients in hospital were a strong and independent predictor of death following acute stroke (odds ratio 1.13 (95% CI 1.01−1.27) for 1 g/1 lower serum albumin concentration).
Calcium levels in maternal milk: relationships with calcium intake during the third trimester of pregnancy
Authors: Ortega Rosa M. , Martínez Rosa M. , Quintas M. Elena , López-Sobaler Ana M. , Andrés Pedro
Published: September 2005

The aim of the present study was to investigate the relationship of Ca intake and serum Ca levels during the third trimester of pregnancy with levels of the same mineral in transition milk (days 13−14 of lactation) and mature milk (day 40 of lactation). The study subjects were a group of fifty-seven healthy, lactating mothers aged between 18 and 35 years (mean 27 (SD3·7) years) whose pregnancies and labour were attended by the Department of Obstetrics and Gynaecology of Cuenca INSALUD Hospital, Spain. Ca intake during the third trimester was determined by recording the consumption of foods over a 5 d period and by registering Ca provided by dietary supplements. The same method was used to investigate the intake of protein, vitamin D, fibre and Fe, nutrients that could affect the use of dietary Ca. Ca levels in maternal serum during this stage of pregnancy, during lactation and in transition and mature milk samples, were determined using 2-cresolphthalein complexone. During pregnancy 70·2% of subjects showed Ca intakes below 1100mg/d (75th percentile). The consumption of Ca supplements was very small and hardly modified the mean quantity supplied by the diet. Subjects with an intake < 1100mg/d showed no fall in Ca levels in serum, either during pregnancy or lactation, nor were decreased levels found in transition milk. However, these subjects showed lower Ca levels in mature milk (5·95 (SD1·56) mmol/1) than did subjects with greater Ca intakes (6·82 (SD1·31) mmol/1). This may suggest that breast-fed babies of mothers with lower Ca intakes during pregnancy also receive less Ca.