bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of chronic ethanol administration on lipogenesis in liver and adipose tissue in the rat
Authors: Cascales Carmen , Benito Manuel , Cascales María , Caldés Trinidad , Santos-Ruiz Angel
Published: June 2005

1. Rates of lipogenesisde novohave been studied in liver and epididymal fat pads of male rats chronically treated with ethanol. A solution of ethanol (150 ml/l) was administered as the only drinking fluid for 3 months with a standard solid diet; both food and drink were availablead lib.

2. Lipogenesis in vivo was measured by the incorporation of tritiated water into lipid fractions: non-saponifiable lipid and fatty acids. Non-saponifiable lipid, both in liver and in adipose tissue, was unaffected by ethanol treatment. However, fatty acid synthesisde novowas significantly enhanced in both liver and adipose tissue, by 150 and 300% respectively.

3. Plasma triacylglycerol and non-esterified fatty acid levels were unchanged and plasma glucose concentration slightly increased by ethanol administration.

4. The rate of lipogenesis increased when insulin: glucagon increased twofold due to the effect of ethanol.
Absorption of methionine and methionine sulphoxide in rat intestine and the effect of glutathione
Authors: Aksnes A. , Njaa L. R.
Published: June 2005

1. The absorption of methionine and methionine sulphoxide was compared in inverted rings from three sections of rat intestine.

2. In all sections, absorption of unoxidized methionine was 20–40% higher than that of methionine at low physiological substrate concentrations. At higher substrate levels, the difference was not so pronounced.

3. Inhibition studies indicated that absorption of methionine and of methionine sulphoxide took place by different absorption systems.

4. Glutathione increased the absorption of methionine and, to a greater extent, the absorption of methionine sulphoxide.
Nature of the effects of bran on digestive transit time in pigs
Authors: Bardon T. , Fioramonti J.
Published: June 2005

1. Transit time of digesta, faecai volatile fatty acids (VFA) excretion and faecal output were measured in four pigs (initially of 90 kg live weight) fitted with chronic catheters inserted into the caecum.

2. Each pig was given a basal milk diet (20 g/kg live weight per d) for 30 d and then received successively four further treatments: the basal diet with bran (100 g/d), the bran-supplemented diet with a daily administration of neomycin (100 mg/kg orally and 100 mg/kg intracaecally), the basal diet with continuous intracaecal infusion of either saline (9 g sodium chloride/1) or with VFA solution (100 mM/h) at the same rate.

3. The mean retention time of the polyvinyl chloride marker was reduced from 98·6 h on the milk diet to 64·3 h on the milk + bran diet. This transit time was notsignificantly modified by neomycin treatment.

4. Daily faecal excretion of VFA was significantly affected by the diet: the additionof bran induced a 167% increase from the milk diet; neomycin treatment reduced VFA excretion with the bran-supplemented diet from 11·3 mM/d to 6·3 mM/d whereas during VFA infusion, excretion levels were twice those of the basal diet.

5. Infusion of VFA solution on the milk diet induced an 11% increase in transit time,without any change in faecal output and dry matter.

6. In conclusion, it is suggested that the decrease in transit time associated with bran supplementation is mediated by direct mechanical factors rather than fermentation products, including VFA.
Dental and metabolic effects of lactitol in the diet of laboratory rats
Authors: Grenby T. H. , Phillips A.
Published: June 2005

1. Because so little is known about the properties of lactitol as a possible alternative bulk sweetener to sucrose, it was tested in two large-scale experiments in laboratory rats. Matched groups of caries-active Osborne-Mendel rats were fed on uniform diets containing lactitol and compared with a sucrose control in both experiments, plus a xylitol control in the first experiment.

2. In the early stages of the experiments weight gains and food utilization were better on the sucrose than on the lactitol regimens. Body-fat storage was higher on the sucrose than on the polyol regimens.

3. At the end of 8 weeks the mandibular molars were examined for dental plaque accumulation and dental caries. The dental caries scores when 160 g sucrose/kg in the diet was replaced by lactitol were lower by a highly significant margin, bringing them down to the same low level as those on a 160 g xylitol/kg regimen.

4. Testing lactitol in a manufactured food product, shortbread biscuits, in comparison with ordinary sucrose biscuits, showed differences in plaque scores (significant) and caries levels (highly significant), with 60% fewer lesions on the lactitol regimen.

5. The results confirm the low cariogenic potential of lactitol, but show metabolic differences compared with sucrose.
Body composition of lactating women determined by anthropometry and deuterium dilution
Authors: Wong William W. , Butte Nancy F. , Smith E. O'brian , Garza Cutberto , Klein Peter D.
Published: June 2005

1. Body fat, fat-free mass and total body water of ten lactating women were estimated from deuterium-dilution spaces and from skinfold thickness measurements. Deuterium-dilution spaces were calculated from the 6 h (equilibration) and zero-time (extrapolation) deuterium enrichments in saliva, urine, human milk and breath water vapour samples.

2. The deuterium spaces obtained by equilibration were statistically larger than those obtained by extrapolation. Isotope dilution spaces derived from deuterium enrichments in saliva, breath water vapour and human milk did not differ with the exception of the 6 h equilibration value of milk, which was greater than that estimated from saliva. Deuterium-dilution spaces estimated from urine were consistently smaller than those derived from the other biological fluids.

3. No significant differences in body fat, fat-free mass and total body water were observed between anthropometric measurements and deuterium-dilution methods, except for extrapolated values derived from deuterium enrichments in urine.
Kinetic aspects of calcium metabolism in lactating sheep offered herbages with different Ca concentrations and the effect of protein supplementation
Authors: Chrisp J. S. , Sykes A. R. , Grace N. D.
Published: June 2005

1. Two experiments are described in which kinetic aspects of calcium metabolism were studied in housed lactating sheep consuming different fresh herbage species. The importance of protein supply was also investigated.

2. In Expt. 1, two groups (n 4) were offered, ad lib., a freshly cut ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) pasture containing 5·48 g Ca/kg dry matter (DM). One group was supplemented daily with 100 g protected casein. A third group (n 4) was offered, ad lib., freshly cut oats-Tama ryegass (Lolium multiflorum L.) herbage which had a lower Ca content of 3·07 g Ca/kg DM. Stable Ca and nitrogen balances were carried out during the first 7 weeks of lactation. At this stage 180 μCi45Ca were administered for Ca kinetic studies.

3. In Expt 2, eight sheep were offered, ad lib., a fresh ryegrass–white clover pasture, and paired on the basis of their udder size. One member of each pair was supplemented daily with 100 g casein via the abomasum and the amount of milk removed was equalized between pairs. Ca and N balances (12 d) and Ca kinetic studies (280 μCi 45Ca) were carried out during weeks 2 and 5 of lactation.

4. Rate of absorption of Ca increased, while rate of Ca secretion in milk and resorption from bone decreased as lactation progressed. Ca balances changed from negative to positive as lactation progressed in sheep offered ryegrass–white clover, but, while improving, were always negative in sheep offered oats–Tama ryegrass. Protein supplementation increased (18%) milk production of the ewes in Expt 1 and their retention of N in Expt 2.

5. The proportion of utilized Ca derived from the diet, as opposed to the skeleton, tended to increase as a result of protein supplementation.

6. Availability of Ca from ryegrass–white clover ranged from 0.19 to 0.32, even though only 50% of the net Ca requirement was derived from the diet. Availability of Ca from the oats–Tama ryegrass diet was similar, though in this case less than 20% of the net Ca requirement was derived from the diet. It was concluded that availability of Ca from forage diets may be lower than previously anticipated.

7. Faecal endogenous loss ranged from 16 to 40 mg Ca/kg body-weight per d, and was similar on both diets.

8. These and other findings are used to discuss more fully the subject of Ca nutrition in sheep, in particular, the implications of the strong homeostatic control of Ca absorption and the influence of protein status on the relative contribution of the diet and the skeleton in meeting the net Ca requirement of the ewe during lactation.
Faecal endogenous loss of calcium in young sheep
Authors: Chrisp J. S. , Sykes A. R. , Grace N. D.
Published: June 2005

1. Two groups of eight 6–7-month-old wether lambs were offered either a frozen ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) pasture or a ryegrass-white clover hay, containing 12.1 and 6.4 g calcium/ kg dry matter (DM) respectively. Within groups the amounts offered to individual sheep ranged from 0.5 to 2.0 times the estimated maintenance energy requirements.

2. A single intravenous injection of 150 μCi 45Ca as CaCl2. 2H2O, and stable balances were used to determine absorption, faecal endogenous loss and balance of Ca.

3. Faecal endogenous loss of Ca increased by 1.2 mg/kg body-weight (W) per d with each g/kg W per d increase in DM intake regardless of the diet. At any DM intake the mean faecal endogenous loss was 5.5 mg/kg W per d higher in the sheep offered the frozen herbage diet when compared with those on the hay diet. At any Ca intake the mean faecal endogenous loss was 6.9 mg/kg W higher in sheep offered the hay diet compared with those on the frozen herbage.

4. At feeding levels of about 1.5–2 times the estimated maintenance energy requirement the observed faecal endogenous loss of Ca ranged from 35 to 50 mg/kg W per d, which is two- to threefold greater than the present estimate of the Agricultural Research Council (1980) of 16 mg/kg W per d.

5. A simple model to explain the variation in faecal endogenous loss of Ca between the present study with young sheep and that with lactating ewes (Chrisp et al. 1989) also offered herbage diets is developed, which incorporates the concept of a true endogenous loss related to DM intake and a net endogenous loss reflecting the extent of re-absorption of Ca endogenous losses within the gastrointestinal tract.
Diet planning for humans using mixed-integer linear programming
Authors: Sklan David , Dariel Ilana
Published: June 2005

Human diet planning is generally carried out by selecting the food items or groups of food items to be used in the diet and then calculating the composition. If nutrient quantities do not reach the desired nutritional requirements, foods are exchanged or quantities altered and the composition recalculated. Iterations are repeated until a suitable diet is obtained. This procedure is cumbersome and slow and often leads to compromises in composition of the final diets. A computerized model, planning diets for humans at minimum cost while supplying all nutritional requirements, maintaining nutrient relationships and preserving eating practices is presented. This is based on a mixed-integer linear-programming algorithm. Linear equations were prepared for each nutritional requirement. To produce linear equations for relationships between nutrients, linear transformations were performed. Logical definitions for interactions such as the frequency of use of foods, relationships between exchange groups and the energy content of different meals were defined, and linear equations for these associations were written. Food items generally eaten in whole units were defined as integers. The use of this program is demonstrated for planning diets using a large selection of basic foods and for clinical situations where nutritional intervention is desirable. The system presented begins from a definition of the nutritional requirements and then plans the foods accordingly, and at minimum cost. This provides an accurate, efficient and versatile method of diet formulation.
Lowering effect of dietary milk-whey proteinv. casein on plasma and liver cholesterol concentrations in rats
Authors: Zhang Xizhong , Beynen Anton C.
Published: June 2005

The effect of dietary whey proteinv. casein on plasma and liver cholesterol concentrations was investigated in female, weanling rats. Balanced, purified diets containing either whey protein or casein, or the amino acid mixtures simulating these proteins, were used. The high-cholesterol diets (10 g cholesterol/kg feed) had either 150 or 300 g protein or amino acids/kg feed. The diets were fed for 3 weeks. At the low dietary protein level, whey proteinv. casein did not affect plasma total cholesterol, but lowered the concentration of liver cholesterol. At the high dietary protein level, whey protein significantly lowered plasma and liver cholesterol and also plasma triacylglycerols. The hypocholesterolaemic effect of whey protein was associated with a decrease in very-low-density-lipoprotein cholesterol. At the high dietary protein concentration, whey protein reduced the faecal excretion of bile acids when compared with casein. The effects of intact whey proteinv. casein were not reproduced by the amino acid mixtures simulating these proteins. It is suggested tentatively that the cholesterol-lowering effect of whey protein in rats is caused by inhibition of hepatic cholesterol synthesis.
Prevention of coprophagy does not alter the hypocholesterolaemic effects of oat bran in the rat
Authors: Jackson Kathryn A. , Topping David L
Published: June 2005

Male rats were fed on either a non-purified rodent diet (JS) or cholesterol-free purified diets containing wheat bran (WB) or oat bran (OB). Some animals were allowed normal access to their faeces for coprophagy (coprophagy +), while in others coprophagy was prevented by placement of a plastic cup over the anus (coprophagy −). Direct ingestion of faeces from the anus was observed in the former groups. Food intake was unaffected by diet or coprophagy status and body weight gain was unchanged with OB − and JS − but was significantly lower with WB −. Plasma cholesterol was highest with WB and equally lower with OB and JS and was unaffected by coprophagy status. Plasma triacylglycerols were highest with OB and were unaffected by coprophagy status. Caecal digesta mass was highest with JS, intermediate with OB and lowest with WB. Digesta mass was unaffected by coprophagy status with WB and JS but was higher with OB −. Digesta moisture content was lowest with WB + but highest with WB −. Digesta volatile fatty acid (VFA) concentrations were similarly lower with OB + and OB −, but were significantly lower with JS − and WB − than in the corresponding coprophagy + group. In all groups digesta butyrate concentrations were reduced by coprophagy prevention. Pools of total VFA, acetate and butyrate in the digesta were highest with JS. Pools of total VFA in digesta were highest with JS +, OB + and OB − and lowest with WB + and WB −. The propionate pool was highest with OB −, intermediate with OB +, and equally low in all other groups. The pool of butyrate was highest with JS + and lowest with OB −. Effects of oats and wheat on plasma cholesterol in the rat do not seem to be mediated through faecal re-ingestion.
Antinutritive effects of wheat-germ agglutinin and other N-acetylglucosamine-specific lectins
Authors: Pusztai A. , Ewen S. W. B. , Grant G. , Brown D. S. , Stewart J. C. , Peumans W. J. , Van Damme E. J. M. , Bardocz S.
Published: June 2005

Incorporation of N-acetylglucosamine-specific agglutinins from wheat germ (Triticum aestivum; WGA), thorn apple (Datura stramonium) or nettle (Urtica dioica) rhizomes in the diet at the level of 7 g/kg reduced the apparent digestibility and utilization of dietary proteins and the growth of rats, with WGA being the most damaging. As a result of their binding and endocytosis by the epithelial cells of the small intestine, all three lectins were growth factors for the gut and interfered with its metabolism and function to varying degrees. WGA was particularly effective; it induced extensive polyamine-dependent hyperplastic and hypertrophic growth of the small bowel by increasing its content of proteins, RNA and DNA. Furthermore, an appreciable portion of the endocytosed WGA was transported across the gut wall into the systemic circulation, where it was deposited in the walls of the blood and lymphatic vessels. WGA also induced the hypertrophic growth of the pancreas and caused thymus atrophy. Although the transfer of the gene of WGA into crop plants has been advocated to increase their insect resistance, as the presence of this lectin in the diet may harm higher animals at the concentrations required to be effective against most pests, its use in plants as natural insecticide is not without health risks for man.
Rape-seed meal toxicity in gnotobiotic rats: influence of a whole human faecal flora or single human strains ofEscherichia coliandBacteroides vulgatus
Authors: Rabot Sylvie , Nugon-Baudon Lionelle , Raibaud Pierre , Szylit Odette
Published: June 2005

Gnotobiotic growing rats harbouring either a whole human faecal flora or single human strains ofEscherichia coli(EM0) orBacteroides vulgatus(BV8H1) were fed for 7 weeks on semi-synthetic diets in which the protein source was either soya-bean meal (SM) or rape-seed meal (RM). For each bacterial status the RM-diet group was compared with the control group fed on the SM diet. The association of human faecal flora with the RM diet was responsible for reduced feed intake and reduced weight gain, an enlargement of the liver and thyroid and a decrease in both thyroxine and triiodothyronine plasma levels. The association of theB. vulgatusBV8H1 strain with the RM diet reproduced all these effects, except that triiodothyronine plasma levels were not significantly modified. Rats inoculated with theE. coliEM0 strain and fed on the RM diet exhibited a goitre and lowered thyroxine and triiodothyronine plasma levels. These results show that the human intestinal microflora may be involved in glucosinolate metabolism when cruciferous vegetables are consumed by man. The specificity of the symptoms observed according to the rat bacterial status supports the hypothesis that bacteria yield specific toxic glucosinolate derivatives according to their enzymic potential.
The influence of proanthocyanidin-rich bean hulls and level of dietary protein on energy metabolizability and nutrient digestibility by adult cockerels
Authors: Longstaff M. A. , Feuerstein D. , McNab J. M. , McCorquodale C.
Published: June 2005

Cotyledons and hulls were prepared from twelve varieties of field beans (Vicia faba L.). Adult cockerels were tube-fed either beans, cotyledons or hull diets containing high or low levels of protein. Metabolizable energy coefficients and starch digestibility coefficients were determined for beans, cotyledons and hull diets. Lipid digestibility coefficients from hull diets were also determined. When cotyledons were fed there were no significant differences in the way in which adult cockerels metabolized energy or digested starch from the proanthocyanidin-free and proanthocyanidin-rich varieties (0·780, 0·908, 0·775 and 0·918 respectively). When beans were fed, however, both energy metabolizability and starch digestibility decreased due to the presence of hulls, with proanthocyanidin-rich hulls decreasing values the most to 0·660 and 0·819 respectively, and proanthocyanidin-free hulls decreasing values to a lesser extent to 0·709 and 0·886 respectively. Diets composed of proanthocyanidin-rich hulls depressed metabolizable energy and maize starch digestibility. Their effect on maize starch digestibility, however, was considerably less than that on bean starch. Lipid digestibility was enhanced by proanthocyanidins but only when the protein content of the diet was high. There was a significant correlation (P < 0·05) between the vanillin and anthocyanidin formation methods for the estimation of proanthocyanidins (r 0·779). There was also a highly significant regression of bean starch digestibility v. proanthocyanidin content of coloured-flowered bean hulls (P < 0·001). The regression of maize starch digestibility v. hull proanthocyanidins was also significant at P < 0·005.
On incorporating diffusion and viscosity concepts into compartmental models for analysing faecal marker excretion patterns in ruminants
Authors: France J. , Thornley J. H. M. , Siddons R. C. , Dhanoa M. S.
Published: June 2005

Deterministic mathematical equations are derived to describe the pattern of marker excretion in the faeces of ruminants under steady-state conditions when diffusion and viscosity concepts are introduced into a simple two-compartment scheme of the gastrointestinal tract. The basic scheme comprises a pure-mixing pool obeying first-order kinetics and a second compartment exhibiting streamline flow. Introduction of a velocity gradient, longitudinal diffusion or both into the second compartment, even with various simplifying assumptions, yields analytically insoluble equations. The impact of these mechanisms is to be investigated numerically rather than analytically in future work.
An integrated, dynamic model of feed hydration anddigestion, and subsequent bacterial mass accumulation in the rumen
Authors: Van Milgen Jaap , Berger Larry L. , Murphy Michael R.
Published: June 2005

Hydration of feeds and bacterial attachment to feed particles are thought to play major roles in rumen digestion of fibrous feedstuffs. The objective of the present study was to integrate these phenomena in a mechanistic model that could be used for data analysis. The proposed model was based on the conversion of biomass, where digestion end-products can be used for the synthesis of bacterial mass. Digestion of the potentially digestible fraction and subsequent accumulation of bacterial mass was based on a sequential, three-compartment model. These compartments represented substrate undergoing hydration, digestion, and bacterial mass accumulation. A fraction of the substrate was used for synthesis of bacterial mass. It was assumed that these bacteria associate either temporarily or permanently with the remaining substrate. Dacron bags containing either dry or fully-hydrated lucerne (Medicago sativa), maize (Zea mays) cobs, orchard grass (Dactylis glomeratd), and wheat straw were incubated in the rumen of a steer that was infused continuously with (15NH4)2SO4. The15N-enrichments of isolated particle-associated bacteria and residue remaining in the bags were used to estimate bacterial attachment. Substrate remaining and microbial mass accumulation were analysed simultaneously. Hydration did not appear to limit digestion. Fractional rate of digestion and appearance of attached bacterial mass was fastest for lucerne. For lucerne, 5 % of the digestion end-products were used for synthesis of bacteria that associated with the substrate, whereas for maize cobs, orchard grass, and wheat straw this was 16, 14, and 19% respectively. Less than 2% of digestion end-products were used for synthesis of bacteria that permanently remained associated with the substrate. Permanent association can occur only with the indigestible fraction, and probably represents bacterial debris. Lysis and/or detachment of bacterial cells was highest for lucerne, and was indicative of the rapid dynamics of lucerne digestion.
Adaptation to the digestion of non-starch polysaccharide in growing pigs fed on cereal or semi-purified basal diets
Authors: Longland A. C. , Low A. G. , Quelch D. B. , Bray S. P.
Published: June 2005

Pigs (25–45 kg) were fed on either cereal or semi-purified basal diets supplemented with either high or low levels of sugar-beet pulp or wood cellulose (Solka-floc). The apparent digestibility and retention of N and apparent digestibility and metabolizability of energy (GE) and the apparent digestibility of non-starch polysaccharides (NSP) and their constituent monomers were measured during weeks 2, 4 and 6 of the trial. N and GE were less well-digested, retained or metabolized from cereal basal diets than from the corresponding semi-purified diets during all three periods. NSP from sugar-beet pulp was highly digestible, unlike that from Soka-floc which was relatively poorly digested. These differences of NSP digestibility were seen more clearly when incorporated in semi-purified diets. There was no significant increase in the digestibility or retention of N, or digestibility or metabolizability of GE, or in the digestibility of sugar-beet pulp NSP with increasing time-period on the diets. In contrast, the digestibility of Solka-floc NSP tended to increase with the time-period. The digestibility of NSP from the semi-purified diet with the high level of Solka-floc inclusion was much lower than that for the low level of inclusion, indicating that microbial activity had been reduced. In conclusion, adaptation to the diets in terms of N and GE balance may be complete after 1 week, but 3–5 weeks may be necessary before stability of measurements of the digestibility of resistant NSP monomers can be obtained.
Protein and energy relationships in the broiler chicken
Authors: Rosebrough R. W. , McMurtry J. P.
Published: June 2005

Male broiler chickens growing from 7 to 35d were fed on a diet containing 150g crude protein (N × 6·25)/kg diet supplemented with lysine to equal that in diets containing 166, 183 and 200g crude protein/kg diet (Expt 1). A second group of male broiler chickens growing over the same period were fed on a diet containing 120g crude protein/kg supplemented with lysine, arginine, tryptophan, threonine and isoleucine equal to that in diets containing 144, 172 and 200g crude protein/kg diet (Expt 2). Growth was improved by lysine supplementation but not to the level attained by feeding 200g crude protein/kg (Expt 1). Lysine, arginine, tryptophan, threonine and isoleucine supplementation of a low-protein diet also improved growth, but growth again fell short of that attained by feeding a diet containing 200g crude protein/kg. Plasma insulin-like growth factor-1 and thyroxine concentrations increased and triiodothyronine decreased as the crude protein level increased from 150 to 200g/kg diet. Supplemental lysine did not affect plasma levels of these hormones. Although dietary crude protein levels noticeably changed rates ofin vitrolipogenesis, changing either the level of a single limiting amino acid or the levels of several limiting amino acids did not change lipogenesis.
Sugar-beet fibre increases cholesterol and reduces bile acid excretion from the small bowel
Authors: Langkilde Anna Maria , Andersson Henrik , Bosaeus Ingvar
Published: June 2005

The effect of addition of sugar-beet fibre to the diet on sterol excretion from the small intestine was studied in nine ileostomy subjects. A constant low-fibre diet was given in two 3 d periods with and without 32 g sugar-beet fibre/d in random order. Care was taken to minimize bacterial alteration of the ileostomy contents. The addition of sugar-beet fibre increased net cholesterol excretion by 52 (SE 9)%(P< 0·01), from 294 (SE 99) to 451 (SE 124) mg/d, and decreased bile acid excretion by 26 (SE 15)% (P< 0·01), from 764 (SE 118) to 567 (SE 96) mg/d. The increased cholesterol and decreased bile acid excretion found with sugar-beet fibre addition is different from the pattern associated with fibre sources such as pectin and oat fibre. The interaction between dietary fibre and sterol metabolism may be mediated, therefore, by different mechanisms depending on the fibre source.
NaFe3+EDTA as a food fortificant: influence on zinc, calcium and copper metabolism in the rat
Authors: Hurrell Richard F. , Ribas Sandra , Davidsson Lena
Published: June 2005

The general acceptance of NaFe3+EDTA for food Fe fortification has been partly restricted by concern over the influence of EDTA on the metabolism of other nutritionally important trace elements and minerals. We have investigated the influence of NaFe3+EDTA, and of increasing dietary levels of Na2EDTA, on Zn, Cu and Ca metabolism in rats fed on Zn-sufficient and Zn-deficient soya-bean-isolate- based diets. With the Zn-deficient diets, changing the dietary Fe compound from FeSO4 to NaFe3+- EBTA significantly (P < 0·05) increased mean apparent Zn absorption from 50·2 to 67·4%. urinary Zn excretion from 2·0 to 4·0% of intake, and Zn retention from 48·2 to 63·4%. Increasing the dietary EDTA level to 1000 mg/kg further increased Zn absorption to 78·1%, urinary Zn excretion to 15·6% of intake and Zn retention to 62·5%. Increased Zn retention was accompanied by a significant increase in weight gain indicating that the extra Zn was available for normal metabolic processes. With rats fed on the Zn-sufficient diet, NaFe3+EDTA and Na2EDTA similarly increased the absorption, urinary excretion and retention of Zn but to a lesser extent. NaFe3+EDTA, however, had no influence on the absorption, urinary excretion and retention of Cu and Ca, and additional Na2EDTA caused only minor increases in Cu absorption and retention and in the urinary excretion of Ca. We conclude that using NaFe3+EDTA as a food fortificant would have no detrimental effect on the metabolism of Zn, Cu and Ca and, in some situations, could improve Zn absorption and retention from low-bioavailability diets.
Assessment of zinc bioavailability: studies in rats on zinc absorption from wheat using radio- and stable isotopes
Authors: Fox Thomas E. , Fairweather-Tait Susan J. , Eagles John , Wharf S. Gabrielle
Published: June 2005

Absorption from wheat intrinsically and extrinsically labelled with 67Zn and extrinsically labelled with 65Zn was measured from 67Zn faecal excretion and 6sZn whole-body retention in rats. There were significant differences between the extrinsically- and intrinsically-labelled 67Zn (P < 0·001), but not between the extrinsically-labelled 65Zn and intrinsically-labelled 67Zn. The effect of chicken meat on the absorption of Zn from intrinsically-labelled wheat was also studied in the rat. Mean Zn absorption from wheat and chicken meat fed separately was 18·5 and 68·2% respectively, and from a mixture of the two containing the same level of Zn was 50·1%. The apparent absorption of Zn from the composite meal was significantly higher than predicted from the results of the foods on their own (P < 0·001).
Intestinal nitrogen and electrolyte movements following fermented milk ingestion in man
Authors: Mahé Sylvain , Marteau Philippe , Huneau Jean-François , Thuillier François , Tomé Daniel
Published: June 2005

The present study focuses on the digestion and absorption of milk and fermented milk (FM) reflected by gastro-ileal N and electrolyte movements in six healthy volunteers. The N and electrolyte content of the intestinal effluents were analysed both at the beginning of the jejunum and in the distal ileum. The gastric half-emptying time of the liquid phase was significantly (P< 0·05) shorter for milk (35 (SE 2) min) than for FM (60 (SE 2) min). The N balance showed that 58 and 50 % of ingested proteins, milk and FM respectively were absorbed between the stomach and the proximal jejunum and that 91 and 90% respectively were absorbed between the stomach and the terminal ileum in 240 min. Evaluation of mineral absorption indicated that 44 and 67% of Ca was absorbed in the duodenum after milk and FM ingestion respectively, and 41 and 11% of Ca disappeared between the jejunum and the ileum respectively. With regards to N and Ca intestinal availability, the present study confirms that FM products represent an interesting source of N as well as minerals for man. This confers on FM a beneficial effect compared with milk especially for lactase (EC3.2.1. 108)–deficient subjects and children with persistent diarrhoea.
The immunological and long-term atopic outcome of infants born to women following a milk-free diet during late pregnancy and lactation: a pilot study
Authors: Lovegrove Julie A. , Hampton Shelagh M. , Morgan Jane B.
Published: June 2005

Infants born to atopic parents have been found to be at high risk of allergy development. The present study investigated the effect of a maternal milk-free diet during late pregnancy and lactation on the immune response and allergy incidence in at-risk and control infants. Atopic mothers were randomly allocated into an intervention group (n 12) or an unrestricted-diet group (n 14) and compared with non-atopic mothers following an unrestricted diet (n 12). The intervention involved a maternal milk-free diet during late pregnancy and lactation. Infants were followed up for 18 months postnatally. A significant fall in maternal serum β-Iactoglobulin (β-Lg)–immunoglobulin G (IgG) antibody levels (P < 0.05) was observed after a 7-week milk-exclusion diet. In maternal and cord serum samples the levels of β-Lg–IgG and α-casein–IgG antibodies were significantly correlated (r 0.89, P < 0.0001 and r 0.71, P < 0.001 respectively). Higher levels of β-Lg–IgG (P < 0.05) were observed in the cord serum samples compared with paired maternal serum samples. Single-blind allergy assessment by a paediatrician at 12 and 18 months showed that the infants born in the non-atopic group had a significantly lower allergy incidence compared with the infants born in the atopic group following an unrestricted diet (P < 0.008 and P < 0.02 respectively). The allergy incidence in the infants born in the atopic diet group was significantly lower compared with that of the atopic group following an unrestricted diet (P < 0.04). It was observed that the atopic nature of the parents significantly affected the allergy incidence in their children. A trend towards a beneficial effect of a maternal milk-free diet during late pregnancy and lactation was also observed in infants born to atopic parents.
The effect of delayed weaning on the development of oral tolerance to soya-bean protein in pigs
Authors: Miller B. G. , Whittemore C. T. , Stokes C. R. , Telemo E.
Published: June 2005

The antibody response to a dietary antigen (soya-bean protein) and the development of oral tolerance was studied in pigs in a family pen system where the piglets are left with their mothers and gradually wean themselves onto a soya-bean-based diet over a 12 week period. In the first experiment three groups of pigs (eight pigs/group) aged either 2, 8 or 13 weeks were immunized with soya-bean protein or ovalbumin (OvA; controls) intra-peritoneally (i.p.) in Quill A adjuvant and subsequently boosted 2 weeks later. All groups showed an IgG response to the injected antigens indicating lack of tolerance induction to the dietary antigen. Interestingly the groups injected with OvA showed an almost identical response to soya- bean protein as the groups injected with soya-bean protein. In a second experiment with a similar protocol, soya bean was withdrawn from the feed before immunization which resulted in lack of response to soya-bean protein in the groups injected with OvA and a lack of response to injected soya-bean protein in the 14-week-old group, indicating that systemic tolerance was established by 12 weeks of age. The results from the two experiments suggest a compartmentalized response to soya-bean protein i.e. local antibody production to dietary soya bean along with systemic tolerance to injected soya-bean protein. The work also suggests that delayed‘natural’weaning may avoid damaging hypersensitivity reactions associated with early weaning.
Effect of condensed tannins in hulls of faba beans (Vicia fabaL.) on the activities of trypsin (EC2.4.21.4) and chymotrypsin (EC2.4.21.1) in digesta collected from the small intestine of pigs
Authors: Jansman A. J. M. , Enting H. , Verstegen M. W. A. , Huisman J.
Published: June 2005

The effects of condensed tannins in hulls of faba beans (Vicia fabaL.) on the activities of trypsin (EC3.4.21.4) and chymotrypsin (EC3.4.21.1) in digesta obtained from the small intestine of pigs were studied. Using four castrated male pigs (mean body weight 83 kg) fitted with both a simple T-cannuIa in the duodenum and a post-valvular T-cannula at the terminal ileum, two experimental diets were tested in a Latin square design. The low-tannin diet (LT) contained 200 g faba bean hulls (cv. Blandine)/kg with a low content of condensed tannins (< 0.1 % catechin equivalents). The high-tannin diet (HT) contained 200 g faba bean hulls (cv. Alfred)/kg with a content of condensed tannins of 3.5 % catechin equivalents. Spot samples of fresh duodenal digesta were taken daily at fifteen time points between 08.00 and 20.00 hours on four consecutive days. Ileal digesta were collected nearly quantitatively on the same days between 08.00 and 20.00 hours over periods of 2 h. Trypsin and chymotrypsin activities in duodenal digesta did not differ between treatments at any time point (P> 0.05). In ileal digesta of pigs given diet HT the mean activity of trypsin was reduced (P< 0.05). The activity of chymotrypsin in ileal digesta did not differ between treatments. Trypsin activity: chymotrypsin activity was somewhat lower in ileal digesta of pigs receiving the HT diet (P< 0.10). The apparent ileal digestibility of crude protein (N × 6.25) was lower for the HT than for the LT diet (0.614v. 0.728;P< 0.05). Condensed tannins are probably responsible for the lower activity of trypsin in ileal digesta of pigs fed on high-tannin faba bean hulls. Various explanations for the absence of effects of condensed tannins on enzyme activity in duodenal digesta are discussed.
Dietary ascorbic acid lowers the concentration of soluble copper in the small intestinal lumen of rats
Authors: Van Den Berg G. J. , YU S. , Lemmens A. G. , Beynen A. C.
Published: June 2005

We tested the hypothesis that ascorbic acid in the diet of rats lowers the concentration of soluble Cu in the small intestine, causing a decrease in apparent Cu absorption. Male rats were fed on diets adequate in Cu (5 mg Cu/kg) without or with 10 g ascorbic acid/kg. The diet with ascorbic acid was fed for either 6 or 42 d. Ascorbic acid depressed tissue Cu concentrations after a feeding period of 42, but not after 6 d. Dietary ascorbic acid lowered apparent Cu absorption after 6, but not after 42 d. The lowering of tissue Cu concentrations after long-term ascorbic acid feeding may have increased the efficiency of Cu absorption, and thus counteracted the inhibitory effect of ascorbic acid. Dietary ascorbic acid caused a significant decrease in the Cu concentrations in the liquid phase of both the proximal and distal parts of the small intestinal lumen. This effect was due to both a decrease in the amount of Cu in the liquid digesta and an increase in the volume of the liquid phase; only the latter effect for the distal intestine was statistically significant. We conclude that ascorbic acid supplementation lowers Cu absorption by decreasing the concentration of soluble Cu in the small intestine.
Modification of energy metabolism by the presence of the gut microflora in the chicken
Authors: Muramatsu T. , Nakajima S. , Okumura J.
Published: June 2005

Whether the association with gut microflora modifies the energy metabolism of chickens was investigated by varying the metabolizable energy consumption level from zero to above the maintenance requirement in the germ-free and conventional states. Single comb White Leghorn chicks were either fasted for 3 d (Expt 1), or fed for 6 d at a fixed daily meal intake of 2, 5 or 8 g/d (Expt 2), or 5, 10 or 15 g/d (Expt 3). Changes in carcass energy deposition and heat production indicated that when no dietary energy was available the presence of the gut microflora could benefit the birds by reducing energy losses, whereas when dietary energy was supplied the efficiency of energy utilization was reduced by the presence of the gut microflora. It was concluded, therefore, that the heavy burden of the gut microflora modifies energy metabolism by exerting a buffering or a counter-productive action on the energy utilization of the chicken.
Absorption of lysine and methionine from the proximal colon of the piglet
Authors: Darragh Alison J. , Cranwell Peter D. , Moughan Paul J.
Published: June 2005

The present study aimed to determine whether lysine and/or methionine are absorbed in nutritionally significant amounts from the proximal colon of milk-formula-fed piglets (15–32 d old; 2.0–7.4 kg liveweight). Piglets, surgically prepared with simple catheters which allowed infusion into the proximal colon, were randomly allocated to one of two milk-formula diets which were either 40 % deficient in lysine (L– diet) or 60% deficient in methionine and 40% deficient in cysteine (S – diet), yet balanced for all other amino acids. The piglets were individually bottle-fed the milk-formula diets seven times daily at 2 h intervals between 08.00 and 20.00 hours. Physiological saline (9 g NaCl/l) or an isotonic solution containing the deficient amino acid was infused via the catheter at each feeding. The experimental procedure followed a cross-over design. Total daily excretions of urinary urea and total N were determined. There were no significant differences (P> 0.05) in urinary N metabolite excretion for piglets infused with amino acids compared with those infused with saline. Lysine and methionine do not appear to be absorbed in nutritionally significant amounts from the proximal colon of the milk-fed piglet.
Effects of three microbial probiotics on postprandial portoarterial concentration differences of glucose, galactose and amino-nitrogen in the young pig
Authors: Rychen G. , Nunes C. SimÕes
Published: June 2005

Postprandial kinetics of porto-arterial concentration differences of glucose (G), galactose (Gal), L-lactic acid (LA) and amino-N (AN) were studied in the piglet after the ingestion of 107colony-forming units (cfu)SporolactobacillusP44 (SP), or 106cfuBacillus cereusIP5832 (AC), or 106cfu of a combination ofLactobacillus acidophilus, L. fermentumandL. brevis(AB)/g feed. Sixteen fistulated piglets (portal vein and brachiocephalic trunk; mean body weight 22 (SD 2) kg) were used. The diet was based on skimmed milk (320 g/kg), barley (300 g/kg), wheat bran (110 g/kg), maize (100 g/kg) and lactose (70 g/kg). The postprandial blood kinetics, four measurements per animal at 1-week intervals, were studied for 6 h after the ingestion of test meals of 400 g basal diet (BD) or this diet supplemented with the bacteria (SP, AC and AB respectively). Areas of porto-arterial concentration differences (APACD) of G, Gal and LA were not influenced by the bacteria supplements. APACD of AN was significantly higher after the ingestion of the SP diet than that estimated for BD.
Diet selection in sheep: The role of the rumen environment in the selection of a diet from two feeds that differ in their energy density
Authors: Cooper S. D. B. , Kyrizakis I. , Nolan J. V.
Published: June 2005

The effect of the energy density (ED) of feeds offered as a choice on the diet selection of sheep, and the relationship between the rumen environment and the diet selected from feeds of different ED were investigated in two experiments. In the first experiment two feeds, L and H, and their mixture M (3:1 w/w) were formulated. All feeds had similar calculated metabolizable protein: metabolizable energy (ME) ratios, but differed in ED (7·4, 8·1 and 10·1 MJ ME$sol;kg fresh feed for L, M and H respectively). The feeds were offered ad lib. either singly or in paired choices (L/M, L/H and M/H; n6 per treatment) to growing sheep. Although the rate of live-weight (Lwt) gain on feed H was higher than on feeds L or M, and the daily rate of feed intake lower, the sheep on feed choices did not consume only feed H. Instead they selected a mixture of both feeds offered, such that the total amount of H consumed per kg fresh feed was similar on choices L/H and M/H. The rate of Lwt gain of sheep on choices L/H and M/H was not different from that achieved on feed H alone. In the second experiment the choice L/H was offered to fistulated sheep (10 months of age, mean Lwt 57·5 kg) in an 8×8 Latin square, with 7 d periods. Treatments were infusions into the rumen (total volume 1 litre) over 4 h on days 1–4 of each period of acid (HC1; Acid 1, 400; Acid 2, 300 and Acid 3, 200 mmol/l), alkali (NaOH; Alk 1, 316; Alk 2, 212 and Alk 3, 109 mmol/l) and control (NaCl; Con 1, 315 and Con 2, 209 mmol/l). Infusate osmolalities (mOs/kg) were 795 (Acid 1), 585 (Acid 2, Alk 1 and Con 1), 390 (Acid 3, Alk 2 and Con 2) and 200 (Alk 3). Infusion treatment significantly affected the diet selection of the sheep (P < 0·05) according to the osmolality of infusate, but not according to rumen pH. During infusions intake of feed H tended to decline with increasing treatment osmolality, whereas intake of L remained constant. The effects on diet selection and feed intake were of a short duration with no carry-over effects. These results show that sheep given a choice between two feeds of different ED select a substantial quantity of the low-ED feed; this diet selection is affected by short-term manipulations of their rumen environment, in a manner that is consistent with the maintenance of effective rumen conditions.
Effect of dietary magnesium level on urinary and faecal excretion of calcium, magnesium and phosphorus in adult, ovariectomized cats
Authors: Pastoor F. J. H. , Van Tklooster A. Th. , Opitz R. , Beynen A. C.
Published: June 2005

Dietary Mg restriction is generally considered to contribute to the prevention of struvite urolithiasis in cats, but its effects on faecal and urinary excretion of Ca and P have not been systematically investigated. The present study seeks to fill the gap. In a 4×4-week crossover study, ovariectomized cats were fed on purified diets containing either 0·40, 0·79,1·59 or 3·17 mmol Mg/MJ (0·19, 0·38,0·76 and 1·52 g Mg/kg diet). Increasing the dietary Mg level from 0·40 to 3·17 mmol Mg/MJ by the addition of extra MgCO3 raised urinary and faecal excretion of Mg from 0·14 to 0·68 mmol/MJ and from 0·28 to 1·66 mmoI/MJ respectively. The 8-fold increase in Mg intake significantly raised urinary excretion of Ca from 0·06 to respectively when the dietary Mg level was raised from 0·40 to 3·17 mmol/MJ. A dietary level of 0·40 mmol Mg/MJ (0·19 g Mg/kg diet) was found to be sufficient to maintain Mg balance in the adult ovariectomized cats fed on the purified diet.
Dietary phosphorus restriction to half the minimum required amount slightly reduces weight gain and length of tibia, but sustains femur mineralization and prevents nephrocalcinosis in female kittens
Authors: Pastoor F. J. H. , Otitz R. , Van Tklooster A. TH. , Beynen A. C.
Published: June 2005

The effects of dietary P restriction to half the recommended minimum level on growth, bone and renal mineralization and urinary composition were studied in female kittens. In two separate experiments, 8-week-old weanling kittens were fed on purified diets containing either 4·6 or 9·2 mmol P/MJ (2·8 or 5·6 g P/kg diet). In the second experiment there was an additional low-P diet in which the Ca concentration was reduced from 9·5 to 4·8 mmol/MJ (7·5 v. 3.8 g Ca/kg diet). P restriction slightly but systematically reduced weight gain (to a maximum of 16%) and growth of the tibia (by 1–4%); the former effect was statistically significant (P < 0·05) between the ages of 15 and 20 weeks in Expt 1 only, and the latter did not reach statistical significance at any time point (P g 0·13). No adverse effect of P restriction was found on mineralization of femur at the age of 39 weeks. Kidney Ca concentrations were significantly lowered (Expt 1, 6 v. 20/μmol/g dry weight, P < 0-001; Expt 2, 7 v. 16/μmol/g dry weight, P < 0-01) in cats fed on the low-P diets, this effect not being affected by the dietary Ca:P ratio. Urinary P concentration was significantly depressed (by 50–96%) after feeding the low-P diets (P < 0-001). P intake did not influence P, Ca and Mg retention during the period of 15 to 39 weeks of age.