bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of subclinical intestinal nematode infection on the diet seletion of growing sheep
Authors: Kyriazakis I. , Oldham J.D. , Coop R.L. , Jackson F.
Published: September 2005

To test the hypothesis that subclinical gastrointestinal parasitism, associated with an impairment in N digestion and metabolism and a reduction in the voluntary feed intake (VFI), could affect the diet selection of sheep given a choice between two feeds that differed in their crude protein (CP) content, twenty-four Texel ×Scottish Blackface ewe lambs growing from 28 to 48 kg live weight (LWT) were given a daily dose of 2500 larvae of the intestinal nematode Trichostrongylus colubriformis; twenty-four similar lambs were used as uninfected controls. Six infected and six control lambs were given a free choice between two pelleted feeds (10·4 MJ metabolizable energy/kg), wilh different CP contents (90 (L) and 214 (H) g CP/kg fresh feed respectively). In addition, eighteen parasitized and eighteen control sheep were given access ad lib. to either feed L, or feed H, or their mixture M (164 g CP/kg; twelve per feed), in order to quantify the effects of the feeds when offered alone, and to test for any interactions between feed CP content and parasitism on the performance of the lambs. Intestinal parasitism reduced significantly (P < 0·001) both the rates of LWT gain (by 30%) and VFI (by 10%). The adult and developing parasitic forms took 4 weeks to establish and develop to a significant adult worm population (as judged by the faecal egg counts and blood variables) and until then there was no effect of parasitism on the performance of the lambs. The diet selection of the lambs given a choice between two feeds was similar between the two groups in the first 4 weeks of the experiment, but differed significantly (P < 0·05) in the second part of the experiment (4th week to the end). Thus, while parasitized lambs had a reduced rate of feed intake, by changing their diet selection they achieved a daily rate of CP intake similar to the control ones. However, since the parasitized lambs had a reduced rate of LWT gain, they also consumed a higher total amount of CP to reach the same LWT. It is concluded that sheep infected daily with a small number of larvae of T. colubriformis and given a choice between two feeds that differ in their protein contents are able to modify their diet selection in order to meet the increased protein requirements resulting from such an infection.
Effects of different supplements on splanchnic oxygen consumption and net fluxes of nutrients in sheep consuming bromegrass (Bromus inermis) hay ad libitum
Authors: Goestsch A. L. , Ferrell C. L. , Freetly H. C.
Published: September 2005

Fifteen sheep (53 kg), with catheters in a hepatic vein, the portal vein and a mesenteric vein and artery, were offered a bromegrass (Bromus inermis) hay (104 g crude protein (CP), 700 g neutral-detergent fibre and 65 g acid-detergent lignin/kg dry matter (DM)) ad lib. with different supplements to determine the effects on net flux of oxygen and nutrients across the portal-drained viscera (PDV) and liver. The sheep were unsupplemented (Control) or received 5 g DM/kg body weight (BW) of ground maize (M), 7 g DM/kg BW of soya-bean hulls (H) or 0.73 g DM/kg BW of a mix of feedstuffs high in rumen-undegradable protein (P). Apparent digestible energy (DE) intakes were 5·3, 10·4, 10·6 and 6·7 (SE 0·74) MJ/d and apparent digestible CP intakes were 37, 50, 79 and 68 (SE 4·3) g/d for Control, M, H and P treatments respectively. Splanchnic tissue oxygen consumption rates were 0·23, 0·32, 0·30 and 0·27 (SE 0·054) mol/h, and oxidative metabolism accounted for 0·46, 0·31, 0·33 and 0·47 (SE 0·051) of DE intakes for Control, M, H and P treatments respectively. Supplements increased (P 0·05) release of α-amino nitrogen (AAN) by the PDV (4·2, 17·5, 19·6 and 18·1 mmol/h for Control, M, H and P treatments respectively). Splanchnic net flux of AAN was not affected by supplement treatments. Hepatic release of urea-N was increased (P 0·05) by supplement treatments (27, 40, 46 and 44 mmol/h for Control, M, H and P respectively); the P treatment increased (P 0·05) and the H treatment tended (P = 0·10) to increase splanchnic release of urea-N (7, 10, 20 and 27 mmol/h for Control, M, H and P treatments respectively). Net flux of glucose across the PDV was -4·6, 1·4, -5·6 and -7·2 (SE 1·65) mmol/h for Control, M, H and P treatments respectively. Hepatic glucose released averaged 23 (SE 2·0) mmol/h and was not affected by treatment. Treatments M and H increased (P 0·05) PDV release of propionate compared with the Control treatment (4·5, 15·5, 16·8 and 7·7 mmol/h for Control, M, H and P treatments respectively). Release of acetate by the PDV was 43, 97, 118 and 67 (SE 23·9) mmol/h for Control, M, H and P treatments respectively. In summary, different supplements of low-quality grass did not increase the efficiency of N metabolism by splanchnic tissues. Treatment P had little effect on net flux across splanchnic tissues of glucose, L-lactate. β-hydroxybutyrate and volatile fatty acids (VFA). Overall, treatments M and H had similar effects on splanchnic net fluxes of VFA and L-lactate whereas butyrate and β-hydroxybutyrate releases by the PDV were increased by treatment M.
Digestibility of krill (Euphausia superba and Thysanoessa sp.) in minke whales (Balaenoptera acutorostrata) and crabeater seals (Lobodon carcinophagus)
Authors: Mårtensson P.-E. , Nordøy E. S. , Blix A. S.
Published: September 2005

Apparent digestible efficiency (% DE) was studied by use of dietary Mn as an inert marker, in minke whales (Balaenoptera acutorostrata) and crabeater seals (Lobodon carcinophagus) which had been eating krill. Median % DE in minke whales (n 5) eating krill of the genus Thysanoessa sp. (energy density (ED) 23·8 kJ/g) was 93 (range 87–93). Median % DE in crabeater seals (n 6) eating krill of the species Euphausia superba (ED 20·8 kJ/g) was 84 (range 79–85), which is significantly lower than the % DE of krill in minke whales (P = 0·008). Since the chemical composition in E. superba and in Thysanoessa sp. is similar, it is suggested that the complex multi-stomached system of minke whales, which contains both chitinase (EC 3.2.1.14)-producing as well as several other types of bacteria, is superior to the single-stomached system of crabeater seals with regard to krill digestion. It is worth noting, however, that the % DE of krill in the crabeater seal is still very high.
Ascorbic acid deficiency in guinea pigs: contrasting effects of tissue ascorbic acid depletion and of associated inanition on status indices related to collagen and vitamin D
Authors: Tsuchiya Harumi , Bates C. J.
Published: September 2005

To investigate the sensitivity of guinea pig tissues to ascorbic acid depletion, as distinct from inanition, young male guinea pigs were maintained with either ascorbic acid restriction or total diet restriction for 8 weeks. One group (A) received no ascorbic acid for 3 weeks, then 0·5 mg/d for 5 weeks; one group (B) was weight-matched by restricted food intake to the first group; a third (marginally deficient) group (C) received 1 mg ascorbic acid/d throughout; a fourth was weight-matched to this group (D); and a fifth group received the control dietad lib.(E). Both of the groups with restricted ascorbic acid intakes (A and C) developed very low tissue ascorbic acid contents, but only the first group (severely deficient group A) also exhibited a severely reduced growth rate. This group also exhibited reduced femur calcium and hydroxyproline contents and reduced skin hydroxyproline content. These changes were not seen in the corresponding weight-matched group (B). Neither plasma alkaline phosphatase (EC3.1.3.1) activity, nor a variety of indices of vitamin D status exhibited changes which could be attributed specifically to reduced ascorbic acid intake and hence to lowered tissue ascorbic acid content. It is concluded that low tissue ascorbic acid levels in guinea pigs clearly alter the connective tissue composition of growing femur and skin, but do not necessarily produce a major, specific effect on vitamin D status. Moreover, the control of inanition is crucial to permit interpretation of the changes in metabolism that are caused by ascorbic acid deficiency.
Lipid deposition in intestine as a possible cause of malabsorption of nutrients in zinc-deficient common carp (Cyprinus carpio)
Authors: Taneja S.K. , Arya P.
Published: September 2005

An experiment was performed to examine the interaction between Zn deficiency and lipid intake in carp. The carp were given a high-lipid diet that was either Zn-deficient (ZD) or Zn-supplemented (ZS), or were pair-fed (PF) the ZS diet to the intake of the ZD group. After 8 weeks the carp were killed and measurements were made of intestinal glucose uptake, levels of DNA, RNA and triacylglycerol, and alkaline phosphatase (EC3.1.3.1) activity in liver and intestine samples. A further group of similar carp were given the same diets but at week 8 were transferred to low-lipid diets, with the exception of half the ZD group. After a further 8 weeks of treatment, carps were killed for biochemical studies. Intestinal [14C]glucose uptake, levels of DNA, RNA and alkaline phosphatase activity in intestine and liver were significantly (P< 0·05) lower in the high-lipid ZD group than in the high-lipid ZS and PF diet groups. The triacylglycerol concentration in the intestine was higher in the high-lipid ZD group than in the other two groups. When the carp were given the corresponding low-lipid diets, the variables measured in intestine and liver of the ZD group were close to those of the other groups. The results of this study demonstrate that lipid, when present in excess in the diet, accumulates in the intestine under Zn-deficient conditions and may reduce the absorption of glucose in carp. The reduced RNA and DNA levels and alkaline phosphatase activity in liver and intestine of ZD fish compared with those of ZS fish given high- lipid diets is proposed to be due to the malabsorption of nutrients linked with lipid deposition in the intestine, rather than their dependence on the level of Zn in the diet.
Maternal protein reserves and their influence on lactational performance in rats 3. The effects of dietary protein restriction and stage of lactation on milk composition
Authors: Pine A.P. , Jessop N.S. , Oldham J.D.
Published: September 2005

The effects of severe protein restriction following parturition on the changes in rat milk composition during lactation were investigated using multiparous female Sprague-Dawley rats caged individually following mating and offered a high-protein diet (H; 215 g crude protein (N × 6·25; CP)/kg dry matter (DM))ad lib. until parturition. Following parturition, half the females continued to receive diet H, whilst the remainder were offered a diet low in protein (L; 90 g CP/kg DM)ad lib. On days 2, 4, 8 and 12 of lactation groups of females from both dietary treatments were used to provide a milk sample. Milk samples were analysed for their lactose (enzymically), protein (binding to Coomassie blue), lipid (gravimetrically) and mineral (spectrophotometrically) contents. The milk lactose concentration of group H increased with stage of lactation (r20·85,P< 0·001). Such an increase was prevented by diet L, and from day 8 of lactation the milk lactose of group L was lower (P< 0·05) than in group H. Group H milk protein concentration did not change during lactation and averaged 90·7 mg/g. Dietary protein restriction reduced the milk protein concentration of group L so that on days 2, 4 and 12 of lactation it was lower (P< 0·05) than that of group H. On day 8 of lactation the milk protein concentration of group L had increased (P< 0·05) and was comparable with that of group H. For group H, milk lipid averaged 166·8 mg/g and was generally unchanged during lactation. Diet L increased (P< 0·01) the milk lipid concentration (205·5 mg/g) compared with diet H and this was also significant on days 4 and 8 of lactation (P< 0·05). Group L milk lipid concentration also increased between days 4 and 8 of lactation (P< 0·05). Milk Na concentration declined during lactation in both dietary groups (P< 0·01) but was unaffected by dietary treatment. Both milk Ca and P concentrations increased (P< 0·01) during lactation in both dietary groups, whilst protein restriction also increased the Ca and P concentrations (P< 0·05). Milk K and Mg concentrations were unaffected by dietary treatment or stage of lactation. This significant alteration in the milk composition of severely protein-restricted dams, while possibly favouring the disposal of greater quantities of energy-yielding nutrients, suggests that equations developed for the estimation of milk production in rats cannot be used under such conditions. Laction: Milk composition: Feed intake: Dietary protien: Rat
Maternal protein reserves and their influence on lactational performance in rats 4. Tissue protein synthesis and turnover associated with mobilization of maternal protein
Authors: Pine A.P. , Jessop N.S. , Allan G.F. , Oldham J.D.
Published: September 2005

The present study was undertaken to investigate the changes in muscle protein turnover involved in the rapid mobilization of protein in rats subjected to severe protein restriction during lactation. Estimates of mammary gland and liver protein synthesis were also made during lactation. Multiparous female Sprague-Dawley rats, caged individually following mating, were offered a high-protein diet (H; 215 g crude protein (N - 6·25; CP)/kg dry matter (DM))ad lib. until parturition. Following parturition, half the females continued to receive diet H, whilst the remainder were offered a diet low in protein (L; 90 g CP/kg DM)ad lib. On days 2, 4, 8 and 12 of lactation, groups of females were used in the estimation of tissue protein synthesis (flooding dose of [3H]phenylalanine) immediately after a milk sample had been obtained. Rates of muscle protein synthesis were unchanged during lactation in group H. The feeding of diet L during lactation reduced the muscle protein synthesis on day 12 to rates that were lower than group H and also the rate on diet L on day 2 (P0·01). However, this fall in muscle protein synthesis was not rapid and muscle fractional synthesis rate (FSR) was different from group H only from day 8 (P0·05). Estimated rates of mammary protein synthesis appeared to be generally unchanged by dietary treatment or stage of lactation. Liver FSR was also unchanged by dietary protein supply or stage of lactation. The effect of dietary protein restriction on liver size and protein content during lactation influenced liver absolute synthesis rate (ASR), and on days 8 and 12 of lactation liver ASR was lower in group L than in group H (P0·001). The loss of muscle protein in rats fed on diet L during lactation (133 mg) occurred mainly between days 2 and 8 of lactation and was primarily associated with a dramatic increase in degradation (13·0% per d), with the decline in synthesis having a much smaller role. A decline in muscle protein degradation during the latter half of lactation was part of the mechanism that prevented excessive muscle protein catabolism. It is thought that the estimation of mammary protein synthesis in the present study was impaired by the milk sampling procedure previously used.
Amino acid composition of the milk of some mammalian species changes with stage of lactation
Authors: Davis Teresa A. , Nguyen Hanh V. , Garcia-Bravo Roselina , Fiorotto Marta L. , Jackson Evelyn M. , Reeds Peter J.
Published: September 2005

To determine whether the amino acid composition of milk changes during lactation, we compared the amino acid pattern (concentration of each individual amino acid relative to the total amino acid concentration) of colostrum with that of mature milk in six mammalian species. In the human, horse, pig and cow, the pattern of amino acids changed between colostrum and mature milk: glutamate, proline, methionine, isoleucine and lysine increased; cystine, glycine, serine, threonine and alanine decreased. In these four species, the total amino acid concentration also decreased 75% between colostrum and mature milk. In the baboon (Papio cynocephalus anubisandPapio cynocephalus anubis/Papio cynocephalus cynocephalus) and rhesus monkey (Macaca mulatta), however, there was little change in the pattern of amino acids between colostrum and mature milk, and total amino acid concentration decreased only about 25% between colostrum and mature milk. Mature milk rather than colostrum was the most similar among the three primates in both amino acid pattern and total amino acid concentration. We conclude, in those species in which total amino acid concentrations decline substantially between colostrum and mature milk, amino acid patterns also change. The presence of a change in amino acid pattern and total amino acid concentration during lactation appears to be unrelated to phylogenetic order.
Absorption of zinc from Iupin (Lupinus angustifolius)-based foods
Authors: Petterson D.S. , SandstrÖm B. , Cederblad Å.
Published: September 2005

The absorption of Zn from a lupin (Lupinus angustifolius) milk fortified with Ca, a bread containing lupin flour (230 g/kg), a sauce containing lupin flour and a sauce containing a lupin-protein isolate was determined in humans by measuring the whole-body retention of radioisotope from meals labelled with 0·02 MBq65Zn, allowing for endogenous excretion of Zn, after 14 d. The absorption of Zn from the Ca-enriched milk (16·2%) and the bread made with lupin flour (27·0%) was similar to literature figures for comparable soya-bean products. The absorption from composite meals made with lupin flour (28·2%) and protein isolate (32·7%) was significantly higher than that reported for comparable soya-bean products. In a second experiment the absorption of Zn from a lupin-milk base and a soya-bean-milk base was compared with that from Ca-supplemented bases. The absorption of Zn from the lupin-milk base (26·3%) was significantly higher than from the soya-bean-milk base (17·6%), and neither was significantly altered by the addition of Ca. Overall the absorption of Zn from lupin-protein foods was found to be higher than from comparable soya-bean products. Lupin milk could be an attractive alternative to soya-bean milk for infant formulas.
Selenium from beef is highly bioavailable as assessed by liver glutathione peroxidase (EC 1·11·1·9) activity and tissue selenium*
Authors: Shi Bing , Spallholz Julain E.
Published: September 2005

The bioavailability of Se from ground beef has been previously found in this laboratory to be greater than that of selenite or selenate when fed to female Fischer 344 rats. In the present study we examined the bioavailability of Se from various commercial portions of beef, the liver, striploin, round, shoulder and brisket. All beef was cooked, freeze-dried, finely powdered and mixed with the other dietary ingredients. The experimental diets were fed to the weanling Fischer 344 rats which had been subjected to dietary depletion of Se for 6 weeks. The bioavailability of Se from the beef diets was compared with that of Se as selenite or L-selenomethionine (SeMet) added to torula-yeast diets. Each experimental diet contained 0·10 mg Se/kg. After 8 weeks of dietary Se repletion, relative activity of liver glutathione peroxidase (EC1·11·1·9; GSHPx) from the different dietary groups compared with that of control animals (100%) was (%): selenite 91, SeMet 122 (P< 0·05), liver 108, striploin 105, round 106, shoulder 106, brisket 103. Se recovery for liver GSHPx was generally highest from SeMet beef muscle = beef liver selenite. Muscle tissue deposition of Se was highest from SeMet beef muscle selenite = beef liver. In addition, the faecal excretion of Se was lowest from the SeMet dietary group and highest from the selenite dietary group. The experimental results suggest that all cuts of beef appear to be highly bioavailable sources of dietary Se when compared with selenite or L-SeMet. Selenjum bioavailability: Beef: Selenite: Selenomethionine
The effects of iron deficiency and iron overload on cell-mediated immunity in the mouse
Authors: Omara Felix O. , Blakley Barry R.
Published: September 2005

The influence of Fe status on cell-mediated immunity was studied in weanling mice fed on Fe-deficient (7 mg Fe/kg), Fe-sufficient (120 mg Fe/kg) and high-Fe (3000 or 5000 mg Fe/kg) diets for 7 weeks. The contact sensitivity (CS) response to dinitrofluorobenzene (DNFB), thein vivodelayed-type hypersensitivity (DTH) response to sheep erythrocytes (SRBC) and the ability of primed spleen cells to transfer DTH response to naive normal mice were suppressed in mice consuming the Fe-deficient diet. High-Fe diets (3000 or 5000 mg Fe/kg) selectively suppressed the CS response to DNFB, but the DTH response to SRBC or the transfer of DTH response by primed spleen cells to naive normal mice remained normal. Spleen cell functions associated with the expression of class II major histocompatibility (MHC) surface antigens, concanavalin A-induced interleukin-2 (IL-2) secretion or the antigen-presenting cell (APC) ability to stimulate antigen-dependent proliferation of an SRBC-specific helper T-lymphocyte clone were not altered by Fe status. However, consistent with the suppressed DTH response in the Fe- deficient mice was the suppressed concanavalin A-induced T-lymphocyte blastogenesis and the interferon-γ (INF-γ) production by spleen cells from mice fed on the Fe-deficient diet. Spleen cells from mice fed on excess levels of Fe in the diet secreted less INF-γ than the control mice, although T- lymphocyte proliferation remained unaffected. Suppression of the cellular immune response associated with Fe deficiency may be related in part to impaired T-lymphocyte proliferation and INF-γ secretion rather than to deficits in IL-2 secretion or APC function.
One-month regular oral nutrition in alcoholic cirrhotic patients. Changes of nutritional status, hepatic function and serum lipid pattern
Authors: Broies Phoung Nhi , Campillo Bernard
Published: September 2005

The effect of a regular oral diet supplying 167 kJ/kg per d (40 kcal/kg per d) on nutritional state, liver function and serum lipid profile was assessed in thirty severely malnourished alcoholic cirrhotic in-patients. Their diet was monitored by a trained dietitian and they were vigorously encouraged to eat all meals served. One month after their entry into the study, protein and energy intakes were significantly higher (P0·001) in keeping with an improvement of their nutritional status as evaluated by means of height-creatinine index, muscular mid-arm circumference, tricipital skinfold thickness (P0·01 for all) and fat mass (P0·001). Assessment of liver function tests showed that levels of aspartate amino-transferase (EC2.6.1.1), y-glutamyl transferase (EC2.3.2.2) and bilirubin decreased (P <0·05,P> 0·02 andP> 0·05 respectively) while prothrombin time values increased (P< 0·05). Similarly, serum albumin increased modestly while transthyretin did not change. Orosomucoid and C-reactive protein decreased (P< 0·001 andP< 0·01 respectively), indicating an improvement of the inflammatory state. Apolipoprotein Al and high-density-lipoprotein (HDL)-cholesterol correlated with several tests of liver function and improved significantly during the study period (P< 0·001 andP< 0·02 respectively). Moreover, changes in cholesterol and HDL-cholesterol correlated with those in transthyretin (P< 0·02 andP< 0·05 respectively). The changes in ApoAl and HDL-cholesterol were greater in patients whose fat mass increased significantly. Our findings show that adequate oral nutrition resulted in a better nutritional status in cirrhotics after 1 month of hospitalization. The serum lipid variables appeared to be more useful indicators of functional liver improvement than the classic liver function tests which rather indicate liver damage.
The effect of meal size on the cardiovascular responses to food ingestion
Authors: Sidery MicHael B. , Macdonald Ian A.
Published: September 2005

Cardiac output (CO; indirect Fick), blood pressure (BP) and heart rate (HR; oscillometry), superior mesenteric artery blood flow (SMABF; Duplex Doppler) and calf blood flow (CBF; venous occlusion plethysmography) were recorded in the fasted state and for 120 min following the ingestion of 1, 2, and 3 MJ, high-carbohydrate meals in eight healthy females. BP was unchanged following food. HR (P < 0.0005) and CO (P < 0.005) rose significantly following all three meals. Integrated increments in CO over the postprandial period were greater after 3 MJ compared with the 1 and 2 MJ meals (P < 0.05). SMABF rose significantly following all three meals. The pattern of blood flow response was significantly different between the 1 and 3 MJ meals (interaction effect P < 0.02, ANOVA), with blood flow after the 3 MJ meal being significantly greater than flow after the 1 MJ meal at 15, 60, and 90 min. Similarly, the pattern of response was significantly different after the 2 and 3 MJ meals (interaction effect P < 0.03, ANOVA), with blood flow being significantly greater at 15 and 90 min after the 3 MJ meal. CBF fell significantly in the first 15 min after the 3 MJ meal and then recovered towards baseline values. No other significant changes in CBF were recorded. There are substantial peripheral and central cardiovascular changes after food in man and there appears to be a relationship between meal size and the extent of these changes.
Effects of rye bran, oat bran and soya-bean fibre on bile composition, gallstone formation, gall-bladder morphology and serum cholesterol in Syrian golden hamsters (Mesocricetus auratus)
Authors: Zhangt Jie-Xian , Lundin Eva , Reuterving Carl-Olof , Hallmans Göran , Stenling Roger , Westerlund Eric , Åman Per
Published: September 2005

The effects of rye bran, oat bran and soya-bean fibre on serum lipids, bile composition and gallstone formation were studied in male Syrian golden hamsters (Mesocricetus auratus). The control groups received fibre-free stone-provoking (O1 diet) or non-stone-provoking (O2 diet) diets. The serum cholesterol levels were lower for all groups fed on the diets supplemented with the dietary fibre sources compared with the control groups. The total content of bile acids in bile was higher in groups given ryebran diets compared with the corresponding controls. The proportion of cholic acid was higher and that of chenodeoxycholic and lithocholic acid lower in the groups given rye-bran-, oat-bran- or soya-bean-fibre-supplemented diets, compared with the corresponding controls. The secondary: primary bile acid ratio was lower in the group given the rye-bran-supplemented O1 diet. The lithocholic:deoxycholic acid ratio was lower in the groups given rye-bran-, oat-bran- or soya-bean-fibre-supplemented diets than in the corresponding controls. A lower frequency of gallstones was observed only for the group receiving the rye-bran-supplemented O1 diet while the lithogenic index was lower in the groups given the rye-bran-supplemented O2 diet. A decreased epithelial volume density of the gall-bladder and an increased smooth muscular volume density were observed in animals given oat-bran- and rye-bran-supplemented O1 diets, whereas for the soya-bean-fibre-supplemented O1 diet, only the smooth muscular volume density was increased.
Increasing intakes of iron reduce status, absorption and biliary excretion of copper in rats
Authors: Yu Shiguang , West Clive E. , Beynen Anton C.
Published: September 2005

High intakes of Fe may impair Cu status, but the underlying mechanism is not known. Male rats, aged 7 weeks, were given purified diets adequate in Cu (8 mg Cu/kg) and containing either 7, 40 or 389 mg Fe/kg. After 6 weeks the concentrations of Fe in liver and spleen were positively related with dietary Fe level and those of Cu were negatively related with dietary Fe level. Increasing Fe intakes reduced apparent absorption and biliary excretion of Cu in a dose-dependent fashion. In individual rats, biliary Cu excretion showed a significant, positive correlation with Liver Cu concentration. It is concluded that increased Fe intakes depress Cu absorption which produces a decrease in plasma and organ Cu concentrations. As a result, biliary Cu excretion is lowered which contributes to achieving Cu balance at high Fe intakes. Because the concentrations of Cu in plasma and bile, and also plasma ceruloplasmin (EC 1.16.3.1) activities, showed much greater percentage reductions with increasing Fe intake than did the concentrations of Cu in organs, it is possible that increased Fe status interferes with the mobilization of Cu stores.
Vitamin B6deficiency experimentally-induced bone and joint disorder: microscopic, radiographic and biochemical evidence
Authors: Massé Priscille G. , Pritzker Kenneth P. H. , Mendes Maria G. , Boskey Adele L. , Weiser Harald
Published: September 2005

In the present study the effect of pyridoxine deficiency on the utrastructure and morphology of bone and its metabolism was examined in the rapidly growing chick. Pyridoxine-deficient animals had tibias of reduced dry weight and cortical thickness. Histomorphometry demonstrated a disproportionately high eroded surface, lower amount of osteoid tissue and reduced mineralized trabecular width. Anterior–posterior radiographs of the tibiotarsometatarsal joint showed reduced secondary ossification centres and coarse trabeculation. Decalcified metaphyseal cartilage showed irregular trabeculas and a markedly reduced amount of Fast-green counterstain matrix suggesting that there is less collagen present and in turn less availability for matrix to be laid down for later calcification. Plasma activity of the bone alkaline phosphatase isoenzyme (EC) 3. 1.3.1) was decreased. Plasma Ca and PO4levels did not vary. The present bone study referring to a pseudo-lathyritic state in which collagen maturation is not completely achieved supports the hypothesis that pyridoxine is an essential nutrient for the connective tissue matrix.
Degradation of polyphenols (catechin and tannic acid) in the rat intestinal tract. Effect on coloic fermentation and faecal output
Authors: Bravo Laura , Abia Rocio , Eastwood Martin A. , Saura-Calixtol Fulgencio
Published: September 2005

Low- and intermediate-molecular-weight polyphenols are usually extracted by using different solvents (e.g. water, methanol, aqueous acetone). The aim of the present work was to study the possible effects of some extractable polyphenols (EPP) on fat and protein digestibilities and on the colonic microflora. Degradability of these compounds through the intestinal tract was also studied. Catechin and tannic acid (TA) were chosen as representatives of the most common basic structures of EPP (flavonoids and gallic acid respectively). Three groups of eight male Wistar rats were given either a control diet free of EPP, or diets containing 20 g/kg dry matter of catechin and TA. Body-weight and food intake were monitored during a 3-week experimental period. Faeces and urine were collected daily during the third experimental week. EPP and fat were determined in faeces, and N in both urine and faeces. Only 3.1 and 4.6% of the ingested catechin and TA respectively were excreted in faeces, indicating that absorption and/or degradation of these EPP had occurred. HPLC analysis of the poly phenolic content of faeces showed qualitative differences between groups. A significant increase of total faecal weight as well as water, fat and N excretion was produced by TA. Catechin only caused an increase in fat excretion.In vitrofermentation assays were also performed to study the effect of EPP on the colonic microflora. Both catechin and TA affected the yield of end-products of fermentation, and were also degraded during the fermentation process.
Consumption of diets containing raw soya beans (Glycine max), kidney beans (Phaseolus vulgaris), cowpeas (Vigna unguiculata) or lupin seeds (Lupinus angustifolius) by rats for up to 700 days: effect on body composition and organ weights
Authors: Grant Grorge , Dorward Patrica M. , Buchan Wendy C. , Armour Julia C. , Pusztai Arpad
Published: September 2005

Feeding trials have been done with rats to assess the effects of long-term (700 d) consumption of diets based on raw cowpeas (Vigna unguiculata; moderate Bowman–Birk inhibitor content, low lectin content), lupin seeds (Lupinus angustifolius; low lectin and protease inhibitor content) or soya beans (Glycine max; high Kunitz inhibitor content, moderate Bowman–Birk inhibitor content, moderate lectin content) or diets containing low levels of raw kidney bean (Phaseolus vulgaris; high lectin content, low Bowman–Birk inhibitor content) on body weight and composition and organ weights. All the legume-based diets reduced feed conversion efficiency and growth rates during the initial 250 d. However, after 250 d the weight gains by rats given legume-based diets were similar to those of controls given the same daily feed intake. Long-term consumption of diets containing low levels of kidney bean significantly altered body composition of rats. The levels of lipid in the body were significantly reduced. As a result, carcasses of these rats contained a higher proportion of muscle/protein than did controls. Small-intestine relative weight was increased by short- and long-term consumption of the kidney-bean-based diet. However, the increase in relative pancreatic weight observed at 30d did not persist long term. None of the other legume-based diets caused any significant changes in body composition. However, long-term exposure to a soya-bean- or cowpea-based diet induced an extensive increase in the relative and absolute weights of the pancreas and caused an increase in the incidence of macroscopic pancreatic nodules and possibly pancreatic neoplasia. Long-term consumption of the cowpea-, kidney-bean-, lupin-seed- or soya-bean-based diets by rats resulted in a significant increase in the relative weight of the caecum and colon.
Dietary effects of faba-bean (Vicia fabaL.) tannins on the morphology and function of the small-intestinal mucosa of weaned pigs
Authors: Leeumen P. Van , Jansam A. J. M. , Wiebenga J. , Koninkx J. F. J. G. , Mouwen J. M. V. M.
Published: September 2005

The objective of the present study was to evaluate effects of condensed tannins in faba beans (Vicia fabaL.) on morphological and functional variables of the small-intestinal mucosa of piglets. In an experiment with young piglets (8–17 kg body weight), fed on either a control diet or a diet containing 200 g/kg of low- or high-tannin faba bean hulls (with < 0·10 and 3·3% catechin equivalents of condensed tannins respectively), morphological and functional characteristics of the jejunal mucosa were determined. Results of the study showed that the morphological variables of the mucosa of the three groups of piglets were similar. Also, no changes due to dietary tannins were observed in sucrase (EC3.2.1.48)–isomaltase (EC3.2.1.10) activity in homogenates of mucosa plus submucosa. However, aminopeptidase (EC3.4.11.2) activity in these homogenates in the proximal part of the small intestine of the animals of the group fed on the high-tannin diet was significantly lower than that in the animals fed on the control diet or the diet with low-tannin hulls (P< 0·05).
Passage rate and total clearance rate from the rumen of cows fed on grass silages differing in cell-wall content
Authors: Bosch Marlou W. , Bruining Marianne
Published: September 2005

Four non-lactating, rumen-fistulated cows were fedad lib. on two grass silages (first cut (FC) and second cut (SC)) harvested at different growth stages, resulting in different crude-protein (CP) and neutral-detergent-fibre (NDF) contents (FC, 152 g CP/kg, 515g NDF/kg and SC, 210 g CP/kg, 442 g NDF/kg). Voluntary intake and rumen contents, total as well as organic matter were higher for silage FC. Fractional passage rate from the rumen, calculated from the logarithmic decline in Cr-NDF rumen pool, was higher for silage FC (0·0395/h and 0·0446/h for silages SC and FC respectively). When fractional passage rates from the rumen were calculated by dividing the intake of indigestible organic matter by the mean rumen poo! of this fraction, the same differences between silages were found, although the actual levels were much lower (0·0258$sol;h and 0·0300/h for silages SC and FC respectively). The results from the present experiment suggest that disappearance rate from the rumen of particles with a size between 1·25 and 0·071 mm is the rate-limiting step in the control of rumen fill.
The effect of protein degradation products in grass silages on feed intake and intake behaviour in sheep
Authors: Os M. Van , Dulphy J.P. , Baumont R.
Published: September 2005

The effects of NH3 and amines on grass-silage intake, intake behaviour and rumen characteristics were studied in sheep. From a single sward, two direct-cut grass silages were prepared, either untreated (WAS) or with 4·51 formic acid/tonne (FAS). Four experimental diets: WAS, FAS, FAS with addition of 2·9 g NH3/kg DM (FAS + N) and FAS with 2·8 g amines/kg DM (FAS + A), were offered ad lib. once daily to four rumen-cannulated wethers in a 4 × 4 Latin square design. Daily DM intake (DMI) tended to be influenced by dietary treatment (P = 0·09). Compared with FAS, DMI was lower for WAS. Addition of NH3 did not alter DMI, whereas amine addition slightly lowered daily DMI. Reduced DMI resulted from lower intake rates during both the principal meal and the subsequent small meals. Lower initial intake rate during the principal meal suggested reduced palatability of WAS and FAS + A. Amines and NH3, however, did not influence chewing efficiency. No treatment effects were observed on total rumen pool size, DM and neutral-detergent fibre content. Furthermore, NH3, and amines did not alter rumen pH, NH3, and volatile fatty acid concentrations to the extent that they could act on chemostatic intake regulation. Amine addition, however, lowered osmolality of the rumen liquid. No treatment effects on rumen motility were observed. In conclusion, daily DMI was not reduced by the addition of NH3, suggesting that NH3per se is not the causal factor in the negative correlations between silage NH3 content and intake observed by other authors. Amines, however, tended to reduce DMI only by their effect at the oro-pharyngeal level of intake control.
Influence of antibiotics and food intake on liver glutathione and cytochrome P-450 in septic rats
Authors: Colomb Virginie , Petit Jean , Matheix-Fortunet Hélène , Hecketsweiler Bernadette , Kaeffer Nathalie , Lerebours Eric , Colin Raymond , Lemeland Jean-François
Published: September 2005

Experimental sepsis in rats induces a restriction in spontaneous food intake and a drop in liver glutathione, cytochrome P-450 (P-450) and aminopyrine demethylase (AD) activity. The present study was designed to assess the effects of antibiotics alone or when combined with food deprivation on these variables. Eighty-nine male Sprague-Dawley rats were assigned to six groups: control (C), acute infection (experimental pyelonephritis, I), acute infection with antibiotics and food givenad lib. (IA), control with antibiotics (CA), acute infection with antibiotics pair-fed to I (IAR), and sham-operated pair-fed to I (SR). Liver glutathione, P-450 and AD activities were reduced by 45·2, 79·8 and 41·2% respectively in group I. Glutathione and AD significantly increased only in those infected rats given antibiotics and allowed free access to food. P-450 did not normalize within the study period in infected rats receiving antibiotics and food repletion. The risk of drug hepatotoxicity in acute septic states is therefore closely related to the nutritional status. From this point of view, nutritional support is almost as important as treatment of infection.
Morphological changes in the rat small intestine in response to riboflavin depletion
Authors: Williams E. A. , Powers H. J. , Rumsey R. D. E.
Published: September 2005

Female Wistar rats were weaned onto a diet deficient in riboflavin and compared with weight-matched andad lib.-fed controls. The effects of riboflavin deficiency on villus morphometry and enterocyte number on the villi in the upper small intestine were studied. Riboflavin depletion was associated with increased villus length and a proportional increase in the number of cell positions along the villi. The total DNA, RNA and protein contents in the intestinal mucosa were not significantly different between any of the groups. Villus hypertrophy in the absence of increased cell number in the small intestine suggests that villus number may be reduced in riboflavin deficiency. Riboflavin deficiency did not influence the number of mucus-producing goblet cells or the amount of mucosal glycoprotein in the small intestine. Impaired production of mucus appeared not to be involved in the structural and functional changes seen in riboflavin deficiency.
Body mass index: a measure of fatness or leanness?
Authors: Nevill Alan M. , Holder Roger L.
Published: September 2005

The relationship between body fat and stature-adjusted weight indices was explored. Assuming the term height2is a valid indicator of a subject's lean body mass, height2/weight was shown to be an accurate measure of percentage lean body mass and, as such, a better predictor of percentage body fat than the traditional body mass index (BMI; weight/height2). The name, lean body mass index (LBMI), is proposed for the index height2/weight. These assumptions were confirmed empirically using the results from the Allied Dunbar National Fitness Survey (ADNFS). Using simple allometric modelling, the term heightpexplained 74% of the variance in lean body mass compared with less than 40% in body weight. For the majority of ADNFS subjects the fitted exponent from both analyses was approximately p = 2, the only exception being the female subjects aged 55 years and over, where the exponent was found to be significantly less than 2. Using estimates of percentage body fat as the dependent variable, regression analysis was able to confirm that LBMI was empirically, as well as theoretically, superior to the traditional BMI. Finally, when the distributional properties of the two indices were compared, BMI was positively skewed and hence deviated considerably from a normal distribution. In contrast, LBMI was found to be both symmetric and normally distributed. When height and weight are recorded in centimetres and kilograms respectively, the suggested working normal range for LBMI is 300–500 with the median at 400.
Characterization of an antithrombotic peptide from α-casein in newborn plasma after milk ingestion
Authors: Chabance Beathice , Jollès Pierre , Izquierdo Carmen , Mazoyer Elisabeth , Francoual Christine , Drouet Ludovic , Fiat Anne-Marie
Published: September 2005

Bovine and human k-caseinoglycopeptides, two antithrombotic peptides derived from the corresponding k-caseins, were detected in physiologically active concentrations in the plasma of 5-d-old newborn infants after ingestion of cow's-milk-based formula or human milk respectively. It is suggested that these two bioactive peptides are released from milk proteins during digestion.
Feed consumption, growth and growth efficiency of rainbow trout (Oncorhynchus mykiss(Walbaum)) fed on diets containing a bacterial single-cell protein
Authors: Perera W. M. K. , Carter C. G. , Houlihan D. F.
Published: September 2005

The aim of the present study was to compare the nutritive value of bacterial single-cell protein (BSCP) with that of fishmeal in rainbow trout (Oncorhynchus mykiss(Walbaum)). Four diets were formulated to contain a total of 458 g crude protein/kg of which 0% was from BSCP in diet 1 (BSCP-0), 25% in diet 2 (BSCP-25), 62·5% in diet 3 (BSCP-62·5) and 100% in diet 4 (BSCP-100); the remainder of the protein was from fishmeal. There were two studies: in study 1, duplicate groups of twenty-five fish were fed on one of the four experimental diets at the rate of 20 g/kg body weight per d for 132 d. Feed consumption rates of individual fish were measured using radiography and the overall apparent absorption efficiency for N in each group was measured over a 2-week period. In study 2, N intake, consumption, absorption and accretion were measured for each fish under controlled environmental conditions (12 h:12 h light-dark regime; 14°). Higher dietary levels of BSCP resulted in significantly higher feed consumption rates but reduced N absorption efficiency and growth rates. However, a diet containing 25% BSCP (75% fishmeal) did not significantly influence growth rates, feed consumption and absorption efficiency compared with a 100% fishmeal diet. The N growth efficiencies were highest in fish fed on the diet containing the highest level of fishmeal and significantly decreased with increasing BSCP content. Construction of N budgets demonstrated that the reduction in growth in fish eating an increasingly larger proportion of BSCP was due to a decrease in N absorption and an increase in the excretion of urea.
The proportion oftransmonounsaturated fatty acids in serum triacylglycerols or platelet phospholipids as an objective indicator of their short-term intake in healthy men
Authors: Mensink Ronald P. , Hornstra Gerard
Published: September 2005

Unfavourable effects oftransmonounsaturated fatty acid (trans-C18:1) isomers on health variables have been reported. Reports on their actual intake, however, are scarce, because of the absence in many nutrient databases of values fortrans-C18:1, and the wide variation in the level oftransfatty acids between different brands of the same product. We therefore examined whether the intake oftrans-C18:1 is reflected bytrans-C18:1 concentrations in serum triacylglycerols or platelet phospholipids. Thirtyeight men received two diets in random order. During the first experimental period twenty men consumed a Western-type control diet for six weeks, and eighteen men consumed a modified diet in which 70% of the fat was replaced by palm oil. After a wash-out period of 3 weeks, regimens were crossed over (second experimental period). The proportion of total fatty acids fromtrans-C18:1 in the diet decreased from 4·7 (SEM 0·27) during the control to 2·1 (SEM 0·16) on the modified diet (P< 0·001).Trans-C18:1 in serum triacylglycerols decreased from 3·5 (SEM 0·13) to 2·8 (SEM 0·11)% (P < 0·001), and in platelet phospholipids from 1·0 (SEM 0·06) to 0·7 (SEM 0·4)% (P < 0·001). After the first experimental periodtrans-C18:1 in the diet correlated withtrans-C18:1 in serum triacylglycerols (r0·41; P = 0·014), and platelet phospholipids (r0·52; P = 0·001). Also, differences in the intake between the two periods correlated with changes in the proportion oftrans-C18:1 in serum triacylglycerols (r0·56; P= 0·001) and platelet phospholipids (r0·58; P < 0·001). These results suggest that analyses of blood lipid fractions can be used to estimate the intake, and to monitor changes in the intake, oftrans-C18:1.
Relationship between dietary Na+ intake, aldosterone and colonic amiloride-sensitive Na+ transport
Authors: Pácha J. , Pohlová I.
Published: September 2005

The effect of changes in dietary Na+ intake on plasma aldosterone levels and electrogenic amiloride-sensitive Na+ transport (Iamil) was studied in the rat distal colon. Five groups of rats were fed on diets containing different amounts of Na+. Estimated Na+ intake ranged from about 400–80000 ?equiv Na+ /kg body weight (BW) per d. Both variables investigated, Iamil and plasma aldosterone, depended non-linearly on Na+ intake. Reduction of the daily Na+ intake increased plasma aldosterone levels and if these levels reached the value 200 pg/ml or more then Iamil was induced. The corresponding Na+ intake was 1300 ?equiv Na+/kg BW per d. Iamil was not observed at lower aldosterone levels and higher Na+ intakes. Aldosterone infusion for 7 d produced similar changes in Iamil compared with dietary Na+-depleted animals and made the estimation of maximum transport capacity of Iamil possible. We conclude that Iamil operates only if Na+ intake decreases below minimal Na+ requirement in growing rats and that the maximum transport capacity of this pathway is reached only after very severe Na+ deprivation.