bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on the protein requirements of growing cattle
Authors: Griffiths T. W.
Published: May 2005

1. Forty-eight Friesian entire male cattle, with an initial live weight (LW) of 135 kg, were used in two experiments to measure the response to increasing levels of dietary protein (9–11 and 7.5–10.5 g nitrogen x 6.25/kg LW0.75) at differing energy levels (800–900 kJ metabolizable energy (ME) kg LW0.75) over 120-d periods. Digestibility and N balance measurements were also made during the experiments. The diets, which were based on barley and soya-bean meal, were individually fed twice daily.

2. In a third experiment, similar diets were given to four similar animals fitted with intestinal cannulas, at constant energy intake but with variations in dietary protein of 7.5–13.5 g N x 6.25/kg LW0.75. Chromic oxide paper was used as a digesta marker.

3. Positive responses in LW gain and N balance to additional protein were found in both experiments but these were significant (P < 0.05) only in the second experiment and were associated with significant (P < 0.01) increases in the digestibility of modified acid-detergent fibre and ME intake.

4. Mean values, which were not significantly different between treatments, for the degradability of dietary protein in the rumen and the efficiency of microbial protein synthesis were 0.57 and 31.3 g/kg organic matter apparently digested in the rumen respectively. Corresponding values obtained by regression analysis were 0.56 and 28.2.

5. The results in general support the Agricultural Research Council (1980) proposals and suggest that undegraded dietary protein was not limiting in these experiments but that rumen-degradable protein levels were limiting on some treatments.

6. Regression analysis indicated that the mean response to additional protein (g LW gain/g N x 6.25) per kg LW was 0.52 in Expt 1 and 0.51 in Expt 2. These responses could be largely explained by increases in ME intakes.

7. Measurements of duodenal amino acid flow showed marked increases in essential amino acids (EAA) across the rumen. However, EAA flows, were not significantly increased at higher N intakes suggesting that protein per se was not limiting in these experiments.
Effects of lα-hydroxylated metabolites of cholecalciferol on intestinal radiocalcium absorption in goats
Authors: Hove Knut
Published: May 2005

1. Intestinal absorption of47Ca was measured by a double-isotope technique in goats treated with 1, 5 or 25 μg of 1,25-dihydroxycholecalciferol (1,25(OH)2D3). The effects of giving 1,25(OH)2D3by intravenous (iv) infusion for 30–36 h were compared at each dose level with the effects obtained by oral administration of 1,25(OH)2D3either in ethanol or protected against rumen degradation in fatty acid pellets.

2. Dose-dependent increments in absorption followed the treatments, with a doubling of absorption at the 1 μg dose and three- to fivefold increases with the 5 and 25 μg doses.47Ca absorption was equally stimulated 2 and 6 d after treatment but had returned to pretreatment levels 12–14 d after treatment.

3. Intravenous and protected oral administration of 1,25(OH)2D3stimulated47Ca absorption to the same extent, in spite of two- to fivefold higher plasma concentrations of 1,25(OH)2D3after iv treatment. Somewhat lower increments in47Ca absorption were seen using ethanol as the vehicle for oral administration.

4. The naturally occurring metabolites 1,24(R),25-trihydroxycholecalciferol and 1,25(S),26-trihydroxy-cholecalciferol had only one-tenth to one-fifteenth the potency of 1,25(OH)2D3in stimulating47Ca absorption, while synthetic lα-hydroxycholecalciferol appeared to be twice as effective as 1,25(OH)2D3when tested at a high (10μg) dose.
Changes in the content of n-6 fatty acids in liver phospholipids in rats as a consequence of partially hydrogenated dietary oils
Authors: Thomassen Magny S. , Rørtveit Torill , Christiansen Erling N. , Norum Kaare R.
Published: May 2005

1. The effects of unhydrogenated and partially-hydrogenated marine and rapeseed oils on the relative content of n-6 fatty acids in rat liver phospholipids were studied by gas–liquid chromatography.

2. The type of dietary oil strongly affected the pattern of n-6 fatty acids in the liver phospholipids even after a relatively short feeding period (3 weeks).

3. With diets deficient in linoleic acid, accumulation of the 20:3 n-9 fatty acid was observed in the animals receiving partially hydrogenated oils, but not in the animals receiving the unhydrogenated marine oil which contained relatively high amounts of polyunsaturated fatty acids of the n-3 family.

4. The results presented are in line with reports in the literature that dietary trans fatty acids may inhibit the desaturation–elongation enzyme systems of rat liver. The observed effects did not appear to be directly correlated to the dietary content of very-long-chain monounsaturated fatty acids.
Modification of glucocorticoid-induced changes in myofibrillar protein turnover in rats by protein and energy deficiency as assessed by urinary excretion ofNT-methylhistidine
Authors: Tomas F. M. , Murray A. J. , Jones L. M.
Published: May 2005

1. The effects of differing degrees of experimental protein-energy malnutrition on the response of myofibrillar protein turnover rates to administration of corticosteroid has been studied in two experiments on rats. The basal control diet, offeredad lib.in each case, contained 40 g protein/kg, and other groups received diets containing 62.5, 95 or 220 g protein/kg at 0.67, 1 or 1.5 times the level of the control energy intake.

2. Daily administration of 25 or 30 mg corticosterone/kg body-weight after 18 d pre-feeding caused an increase in plasma protein, glucose and insulin concentrations, but a decrease in the corticosterone: insulin values. Liver size and protein content increased, as did the fractional excretion of dietary nitrogen as urea-N in all treated groups. However, whereas a fall in food intake and body-weight occurred in one experiment the reverse occurred in the other.

3. NT-Methylhistidine excretion was 12% lower for rats receiving 40v.220 g protein/kg diet and excretion was increased by only 57v.90% respectively, when the two groups of rats were given 30 mg corticosterone/kg per d. Rats which received 25 mg corticosterone/kg per d and up to 95 g protein/kg diet increased excretion of NT-methylhistidine by an average 35%.

4. The fractional degradation rate of myofibrillar protein (kd) was reduced by about 10% by the low-protein diet from 3.1 to 2.8%/d. During corticosterone treatment the increment inkdfor rats on this diet was only 60% of that for rats receiving the 220 g protein/kg diet, i.e. an increase of 1.8v.3.0%/d. Energy restriction further reducedkdduring low-protein intake but did not affect the response to the corticosterone. Variations in dietary protein from 40 to 95 g/kg had little effect on the increase inkdduring steroid treatment. The effect of corticosterone on calculated synthesis rates (kg) differed markedly between experiments. Whilekgfell by 50–65% in rats which lost weight on treatment, it rose by up to 60% in rats where carcass non-collagen-protein accretion remained unchanged or increased, despite an increase inkd

5. Protein deficiency decreases the catabolic response to glucocorticoid, but the net metabolic response appears crucially dependent on changes in food intake or the stage of growth of the rat or both. A net anabolic response with increased fractional rates of myofibrillar protein breakdown, synthesis and accretion was observed in growing rats fed on relatively-low-protein diets and given 25 mg corticosterone/kg per d. This novel finding indicates that a particular role for cortisol in the adaptation to protein-energy malnutrition by humans should be ascribed only with caution.
Alteration of regression of cholesterol accumulation in rats by dietary pectin
Authors: Thomas James N. , Kelley Michael J. , Story Jon A.
Published: May 2005

1. Male, Wistar rats (50–74 g) were given a semi-purified diet containing cholesterol (10 g/kg diet) for 4 weeks, groups of control and experimental animals killed, and the remainder of the cholesterol-fed animals given either a semi-purified cholesterol-free diet without a fibre source or a similar diet with pectin (50 g/kg diet) for 8 weeks. Animals were killed at 2-week intervals and serum and liver cholesterol and triglycerides, faecal neutral steroids and acidic steroids measured.

2. Animals given pectin had significantly lower serum cholesterol levels than animals given the basal diet after 4 and 6 weeks.

3. Both experimental groups efficiently decreased their liver cholesterol levels during regression.

4. Bile acid excretion was elevated in both groups, especially in rats receiving pectin, but neutral steroid excretion was unchanged.

5. The increase in bile acid excretion was primarily in the form of chenodeoxycholic acid and its metabolites.

6. This increased bile acid excretion is postulated to result from stimulation of the normal mechanism for increased steroid excretion in the rat, i.e. a change in the value of cholic: chenodeoxycholic acid or from a mechanism not yet elucidated.
Sugars-eating habits of 405 11- to 14-year-old English children
Authors: Hackett Allan F. , Rugg-Gunn Andrew J. , Appleton David R. , Allinson Marion , Eastoe John E.
Published: May 2005

1. Between September 1979 and July 1981, 405 northern-English children, initially aged 11–12 years, each recorded all food and drink consumed on five occasions on each of three consecutive days. Sugars and nutrient intakes were calculated using food tables.

2. The average total sugars intake was 118 g/d or 21% of the energy in take and 43% of the carbohydrate intake; these percentages were similar for both sexes, all social class groups and surveys.

3. Sugars were found to be derived from a variety of food sources with confectionery being the single largest source.

4. Sugars were fairly evenly consumed over the average day with a high amount in foods eaten between meals. Snacks accounted for 65% of the sugars intake but only 46% of the energy intake.

5. Sugars intake and snacking therefore seem to have been major components of the eating habits of these children. If dietary changes towards lower sugars intakes are to be achieved a vigorous, informed health education campaign is necessary together with effective labelling of manufactured foods, the development of new products and the modification of some existing ones.
The Bacon Chow study: effect of nutritional supplementation on maternal weight and skinfold thicknesses during pregnancy and lactation
Authors: Adair Linda S. , Pollitt Ernesto , Mueller William H.
Published: May 2005

1. Effects of a feeding programme on maternal weight, triceps and subscapular skinfolds during pregnancy and lactation were assessed in a marginally undernourished population of rural Taiwan. Mothers participated during two pregnancy and lactation periods. At 3 weeks after the delivery of the first infant, one group of 114 mothers began consuming a nutrient-dense supplement (A), while another group of 111 received a placebo (B).

2. There was no significant A–B difference in pregnancy weight gain (A 7.52 kg, B 7.75 kg) or in mean maternal weight, triceps or subscapular skinfolds at any time during pregnancy or lactation. Despite a general trend toward moderate weight loss during lactation, one-third of mothers in both groups gained weight. Highly significant increases in weight and skinfold thicknesses from one lactation period to the next characterized both groups.

3. The absence of demonstrable supplement-effects on maternal anthropometry concomitant with increments in infant birth weight supports the notion that infants can benefit from maternal supplementation without changes in maternal nutritional status.
The effect of ispaghula (Fybogel and Metamucil) and guar gum on glucose tolerance in man
Authors: Jarjis H. A. , Blackburn N. A. , Redfern J. S. , Read N. W.
Published: May 2005

1. The effects of incorporating Fybogel (3·5 and 7 g doses), Metamucil (7 g) or guar gum (2·5 and 14·5 g doses) in a drink containing 50 g glucose on plasma glucose, plasma insulin and gastric emptying were studied in thirty-eight normal volunteers. In addition, the effects of Fybogel (7 g) on glucose tolerance, plasma insulin and gastric emptying were measured in fourteen non-insulin-dependent diabetics.

2. Both doses of guar gum significantly lowered plasma glucose and plasma insulin responses to the oral glucose load in normal subjects, although 14·5 g guar gum did not delay the half-time for gastric emptying.

3. Neither Fybogel nor Metamucil had significant effects on plasma glucose responses in normal subjects. In addition, Fybogel (at either dose) had no significant effects on plasma insulin levels, or on gastric emptying in normal subjects or on plasma glucose and insulin responses in diabetic patients.

4. The viscosity of ispaghula solutions (Fybogel) was lower than that of guar gum solutions.
High efficiency of energy utilization in ‘cafeteria’- and force-fed rats kept at 29°
Authors: Barr H. Gillian , Mccracken K. J.
Published: May 2005

1. Male, Sprague-Dawley (Charles-River) rats, of initial weight 272 g, were given a powdered stock diet (T1) ad lib. force-fed a synthetic diet (T2) or offered a range of palatable foods in conjunction with the powdered stock diet (T3) or a similar diet supplemented with certain minerals and vitamins (T4).

2. Metabolizable energy (ME) intake (kJ/d) averaged 303, 453, 402 and 383 for T1, T2, T3 and T4 respectively and corresponding weight gains were 5.5, 6.9, 8.2 and 7.9 g/d and were significantly different (P < 0.001).

3. The intakes of T3 and T4 rats ranged from 10 to 60% above the mean value for T1.

4. Crude protein (CP; nitrogen × 6.25) retentions were similar for T1, T3 and T4 rats and significantly lower (P < 0.01) for T2 rats. Fat retentions were 1.1, 4.1, 2.9 and 2.4 g/d for T1 to T4 respectively (P < 0.001).

5. The energy contents of the gain (MJ/kg) were 12.7, 26.0, 16.7 and 14.9 for T1 to T4 respectively (P < 0.001) and energy retentions (kJ/d) were 70, 179, 139 and 117 respectively (P < 0.001).

6. A linear regression of energy retention (ER) on ME yielded a slope of 0.78 and a mean energy requirement for zero balance of 510 kJ/kg body-weight0.75.

7. These results are in conflict with reports of ‘diet-induced thermogenesis’ in ‘cafeteria’-fed rats.
The effect of over-feeding newborn rabbits on somatic and visceral growth, body composition and long-term growth potential
Authors: Spencer S. Andrew , Hull David
Published: May 2005

1. Newborn rabbits were over-fed by encouraging them to suck from two lactating does. These double-fed animals were compared with single-fed litter-mate controls.

2. Single- and double-fed rabbits were compared with respect to body-weight, bone length and weights of heart, kidney, lung, liver, spleen, stomach, brain and adipose lobes at ages 7, 14 and 21 d and at 25 weeks. Body composition with respect to fat, protein and water was also analysed in animals killed during the first month of life.

3. Double feeding had a profound effect on body-weight, such that by 21 d of age these animals weighed 65% more than controls. Longitudinal growth was also increased, but to a lesser extent. Organ weights were largely determined by body-weight with the exception of the brain which was unaffected by double feeding and the heart and adipose lobes which were represented to excess. Body composition studies demonstrated a marked increase in body fat and a decrease in body water as a percentage of body-weight in the double-fed.

4. When mature, double-fed rabbits weighed a little more than controls and had accumulated significantly more fat. No other difference between them was demonstrated.

5. Other experiments on rats, mice and pigs, along with these experiments on rabbits, suggest that young mammals respond to over-feeding with a limited increase in real growth associated with excess deposition of adipose tissue. Studies on infants of diabetic mothers have demonstrated that the human fetus responds to over-nutrition in a very similar way. Therefore we should be cautious about over-feeding human infants, especially premature ones, as it seems unlikely that excessive deposition of fat will be beneficial.
Dietary components and plasma insulin responses to fasting and refeeding in genetically obese hyperglycaemic (ob/ob) mice
Authors: Flatt Peter R. , Bailey Clifford J.
Published: May 2005

1. To investigate the role of dietary components in the hyperinsulinaemia of the obese hyperglycaemic (ob/ob) syndrome, plasma insulin responses to fasting and refeeding were examined in Aston ob/ob mice supplied with standard diet, non-digestible-carbohydrate test food, and isoenergetic test foods from which either carbohydrate, protein or fat was omitted.

2. During fasting, plasma insulin concentrations fell more rapidly and to a greater extent than plasma glucose. Refeeding the standard diet raised insulin concentrations above normal, associated with a 25% compensatory increase in food intake over 24 h.

3. Test foods supplied to previously fed or fasted mice produced glucose responses consistent with the available carbohydrate content. Carbohydrate-free food (protein and fat) provided a small insulinotropic stimulus; the effect of protein-free food (carbohydrate and fat) was greater; and the combination of carbohydrate with protein (fat-free food) evoked a marked insulin response. In contrast, insulin concentrations declined in mice given the non-digestible-carbohydrate food.

4. Consumption of the standard diet was increased after 24 h feeding non-digestible-carbohydrate food, but was unaffected by a 30 h fast initiated 54 h previously.

5. These results demonstrate that hyperinsulinaemia in ob/ob mice is not merely triggered by the ingestion of bulk, but depends on the type of nutrient ingested. Dietary carbohydrate appears to be the major stimulus to the hyperinsulinaemia, with an important augmentation in the presence of protein. Since direct glucose stimulation of insulin release is defective in ob/ob mice, the hyperinsulinaemia must be mediated by increased activity of the enteroinsular axis.
The effects of food restriction and exercise on site-specific differences in adipocyte volume and adipose tissue cellularity in the guinea-pig
Authors: Pond Caroline M. , Mattacks Christine A. , Sadler Dawn
Published: May 2005

1. The volume and number of adipocytes were measured in fourteen anatomical sites of adult guinea-pigs kept in small cages and fedad lib.kept in small cages and on restricted diet or fedad lib.and exercised.

2. In the sedentaryad lib.-fed animals, there was no significant correlation between percentage body-weight as adipose tissue, as determined by direct dissection, and mean adipocyte volume based on samples from many different sites. The correlation was significant, though not high, for sedentary, restricted-diet animals and for exercised specimens.

3. The correlations between the volume of adipocytes from left–right pairs of sites, and from sites around the same limb, were highly significant under all conditions studied. The correlation between the volume of adipocytes from sites other than left–right pairs of sites was weaker and in some cases statistically insignificant in sedentaryad lib.-fed guinea-pigs. The volume of adipocytes from sites in the groin region, the mesenteries and medial to the trapezius muscle failed to correlate in many cases with the volume of adipocytes from other sites sampled.

4. The number of adipocytes at each site was similar in the exercised and sedentaryad lib.-fed animals. The restricted-diet, sedentary group had fewer adipocytes at all sites studied except the omental and mesenteric fat mass and the groin sites.

5. It is suggested that moderate regular exercise or fasting gives rise to closer coordination between adipocytes at different sites because central factors regulating adipocyte volume become more prominent than local factors.
The effects of food restriction and exercise on site-specific differences in adipocyte volume and adipose tissue cellularity in the guinea-pig
Authors: Pond Caroline M. , Mattacks Christine A. , Sadler Dawn
Published: May 2005

1. Two intermuscular adipose depots, the popliteal mass (POP) and the fat under the gluteus superficialis muscle (GLS) were studied in guinea-pigs maintained under three different regimes of diet and exercise.

2. Eleven different sites in POP and four sites in GLS were defined using associated muscle and fascia as ‘landmarks’. Samples of twenty to twenty-five adipocytes from each site were removed and their mean volume measured; a consistent pattern of distribution of larger and smaller adipocytes within POP and GLS was found in all animals.

3. The correlation between the volume of adipocytes from sites between the same pairs of muscles was substantially greater than the correlation between the volume of adipocytes from comparable sites between different muscles, whether the sites were within the same fat mass (POP) or in different fat masses (POP and GLS).

4. The volume of adipocytes from the edge of the fat mass correlated more closely with those from the edge of the same or a synergistic muscle than with the volume of cells from the centre sites or edge sites from an interface with another muscle. These effects were most pronounced in exercised animals and weak or insignificant in sedentary ad lib.-fed animals.

5. The volume of adipocytes from edge sites correlated with the gross weight of the adjacent muscles in exercised animals only.

6. It is concluded that muscle activity has a local effect on the volume of adjacent adipocytes. It is suggested that the mechanism involved is mechanical rather than biochemical.
Is phenylalanine requirement in infants and children related to protein intake?
Authors: Kindt Elisabeth , Motzfeldt Kristina , Halvorsen Sverre , Lie Sverre O.
Published: May 2005

1. Two groups of children with phenylketonuria (PKU) received protein at two different levels. The protein scource was a protein hydrolysate, devoid of phenylalanine, and intact protein from milk, vegetables and fruit. One group (RDA group) was given protein at a level based on the recommendations of the (US) Food and Nutrition Board (1974, 1980). The other group (FAO group) was given protein at the level of intake corresponding to the Joint FAO/WHOad hocExpert Committee (1973) safe levels of intake of egg or milk protein. The children were monitored very closely for several years. From an earlier study evaluating the protein intake of the two groups it was suspected that the Joint FAO/WHOad hocExpert Committee (1973) recommendations were marginal.

2. In the present study the phenylalanine intake of the two groups required to maintain the plasma phenylalanine concentration at the required level was established. The results showed that the RDA group required more phenylalanine than the FAO group. This difference was statistically significant from the age of 5–15 months.

3. We have interpreted the greater requirement for phenylalanine in the RDA group as a result of a greater nitrogen intake and thus a more rapid chemical maturation of N (increase in protein concentration of the body with age). It is known that up to the age of 6 months the chemical maturation of N is related to the N intake. In the present study we have found that this difference in chemical maturation lasted up to the age of 15 months. The conclusion drawn from the study was that a protein intake slightly higher than the Joint FAO/WHOad hocExpert Committee (1973) recommendations might be desirable.
The effect of vitamin E and oxidized fish oil on the nutrition of rainbow trout (Salmo gairdneri) grown at natural, varying water temperatures
Authors: Cowey C. B. , Degener Elizabeth , Tacon A. G. J. , Youngson A. , Bell J. G.
Published: May 2005

1. Groups of rainbow trout (Salmo gairdneri) of approximate mean initial weight 8 g were grown in outdoor tanks over a 14-week period at water temperatures between 12° (start) and 6° (end). Four diets were used. Two contained non-oxidized fish oil (120 g/kg) with or without supplementary DL-α tocopheryl acetate and two contained moderately oxidized fish oil again with or without DL-α-tocopheryl acetate. The measured selenium content of the diets was 0.10 mg/kg.

2. No significant differences occurred as a consequence of the use of moderately oxidized oil compared with the corresponding treatments using non-oxidized oil. Significant differences did occur between dietary treatments that contained supplementary DL-α-tocopheryl acetate and those that did not. These differences applied to weight gain, haematocrit, erythrocyte fragility, mortalities, liver and muscle tocopherol concentrations and lipid peroxidation of liver mitochondriain vitro.Liver glutathione peroxidase (EC1.11.1.9) activity was unaffected by the dietary treatments used and the proportions of fatty acids in polar lipids of liver and muscle were little changed by the diets used. Severe muscle damage occurred in trout given diets lacking supplementary DL-α-tocopheryl acetate.

3. Previous experiments carried out on rainbow trout at a constant water temperature of 15° (Hunget al.1981; Coweyet al.1981, 1983), using diets lacking supplementary vitamin E, did not lead to differences in weight gain, pathological changes or mortalities.

4. Vitamin E requirement may increase as water temperature decreases; minimum dietary requirements for vitamin E measured at a constant water temperature of 15° may not be valid under practical conditions where water temperatures vary over the year.
The effect of dietary restriction on muscle fibre length in mice
Authors: Hooper A. C. B.
Published: May 2005

1. The dietary intake of male mice from a line selected for high body-weight was restricted to 60% by weight of thead lib.intake of the control litter-mates between days 21 and 42 post partum.

2. One group was killed and compared with controls at 42 d of age. A further group then resumedad lib.feeding. Mice which had regained the control body-weight by 61 d of age were killed and also compared with controls.

3. Muscle weight, fibre length, sarcomere length, sarcomere number per fibre, actin length and myosin length were measured in the biceps brachii and tibialis anterior muscles.

4. Muscle weight, fibre length and the number of sarcomeres per fibre were significantly reduced in both muscles following dietary restriction, but regained their control values following a resumption of normal feeding. The other indices remained unchanged throughout the study.

5. The pattern of fibre length changes, due entirely to alterations in sarcomere number, is similar to that reported previously during growth, senescence and immobilization and following selection for high and low body-weights.
The role of condensed tannins in the nutritional value of Lotus pedunculatus for sheep
Authors: Barry T. N. , Duncan S. J.
Published: May 2005

1. Voluntary intake was determined with vegetativeLotus pedunculatuscut and fed fresh to growing sheep of 42–46 kg live weight. Effects attributable to condensed tannins were assessed by growing the plant under high and low levels of soil fertility, inducing low and high concentrations of tannin (Expt 1), or by binding the tannins through spraying the herbage with polyethylene glycol (molecular weight 3350, PEG; Expt 2). Primary-growth lotus was used in Expt 1 and secondary-growth lotus in Expt 2. Concentrations of total and free condensed tannin were determined in fresh lotus, free tanning being defined as that not bound by mascerates of the plant.

2. In Expt 1 the herbages fed contained respectively 46 and 106 g total condensed tannin/kg dry matter (DM) and 3 and 14 g free condensed tannin/kg DM. Mean metabolizable energy (ME) intakes were 0.89 and 0.77 MJ/kg live weight0.75per d (P< 0.05) respectively.

3. The lotus used in Expt 2 contained 63 and 5 g total reactive condensed tannin and free condensed tannin/kg DM respectively. After spraying with PEG at 2.4 g/g total condensed tannin, these values were reduced to 7 and 0.5 g/kg DM respectively. PEG addition increased apparent digestibility (proportion of each nutrient ingested) of cellulose, hemicellulose and nitrogen by 0.05, 0.08 and 0.26, and increased ME intake from 0.48 to 0.69 MJ/kg live weight0.75per d.

4. It was concluded that high concentrations of condensed tannins depressed ME intake, due to depressions in both the voluntary intake and digestion of organic matter. The stimulation of hemicellulose and cellulose digestion by PEG addition suggests that the condensed tannin was depressing rumen digestion.

5. It is considered that free tannins are most likely to have been responsible for the depressive effects in the present study. This could be due to their reaction with microbial enzymes in the rumen, the tannin content of the plant exceeding the capacity of the plant protein to bind it, or to reaction with enzymes secreted into the small intestine following the absorption of amino acids. In either instance free tannins could also react with proteins of the gut wall.
Absorption kinetics of some carbohydrates in conscious pigs
Authors: Rerat A. A. , Vaissade P. , Vaugelade P.
Published: May 2005

1. Concentrations of reducing sugars, glucose, fructose and lactic acid in blood obtained from arterial and portal catheters were measured for periods of 8–24 h in twenty-three unanaesthetized pigs (mean body-weight 50 kg). From 6 to 8 d after implantation of catheters, the animals received experimental meals containing different levels (400, 800, 1200, 1600 g respectively) of different sugars (glucose ten meals, sucrose eighteen meals, lactose nine meals, maize starch sixteen meals) as well as a protein–mineral–vitamin premix.

2. After each meal the reducing sugars appeared in the portal blood in successive waves. The porto-arterial differences in the concentration of reducing sugars, representing the real appearance of sugar-hydrolysis products in the animal, varied greatly according to the sugar ingested and its level of intake. For each level of intake, these differences were larger, but of shorter duration, for glucose and sucrose than for maize starch. For these three carbohydrates, the higher the level of ingestion, the larger and the more persistent the porto-arterial differences. Lactose represented a special case, as the porto-arterial differences of reducing sugars were always much lower than those obtained with the other sugars and they did not vary with the level of intake.

3. Our findings show that the products formed by feeding glucose and sucrose appear more rapidly in the portal blood than those formed by feeding lactose. Accordingly, the length of time of digestion of glucose and sucrose is shorter than that of maize starch and lactose.
Absorption kinetics of some carbohydrates in conscious pigs
Authors: Rerat A. A. , Vaissade P. , Vaugelade P.
Published: May 2005

1. Concentrations of reducing sugars, glucose, fructose and lactic acid in blood obtained from arterial and portal catheters were measured together with the portal hepatic blood flow-rate for periods of 8–24 h in twenty-six unanaesthetized pigs (mean body-weight 51 kg). The animals received experimental meals containing different amounts (100–1600 g) of different sugars (glucose fifteen meals, sucrose twenty-four meals, lactose fourteen meals, maize starch nineteen meals) together with a protein–mineral–vitamin mixture (150 g) 6–8 d after implantation of the catheters and an electromagnetic flow probe.

2. Because the portal blood flow pattern did not differ between test meals, net absorption followed the same trends as for porto-arterial concentration differences (Rératet al.1984). Apart from lactose, the amounts of reducing sugars appearing in the portal vein correlated with the intake of the test meal, but the absorption pattern was different for each sugar. The appearance of reducing sugars was faster and earlier after intake of glucose than after sucrose and the same was the case for sucrose relative to maize starch. The differences between the three carbohydrates tended to increase with the level of intake.

3. With a test meal containing 1 kg carbohydrate, i.e. a normal meal in a 50 kg pig, digestion of sucrose and maize starch was not finished 8 h after the meal since only 60 and 52% respectively of their hydrolysis products were recovered in the portal blood. In the case of lactose, the amounts of reducing sugars appearing in the portal blood were always very small and constant (113–118 g within 8 h) whatever the level of intake, i.e. 30 and 15% of their hydrolysis products for intakes of 400 and 800 g respectively.

4. Depending on the carbohydrate ingested, the uptake of glucose by the gut cell wall ranged from 14 to 21 g/h and the production of lactic acid from 2.5 to 3.5 g/h.
Influence of caecectomy and source of dietary fibre or starch on excretion of endogenous amino acids by laying hens
Authors: Parsons Carl M.
Published: May 2005

1. Two experiments were conducted to evaluate the effects of caecectomy and source of dietary fibre and starch on excretion of amino acids by laying hens. In Expt 1, caecectomized hens excreted significantly higher levels of several amino acids than intact hens during a 24 h fasting period. These differences were greatest for threonine, proline and leucine.

2. In Expt 2, caecectomized and intact hens were given either a nitrogen-free diet containing 500 g cellulose/kg or one containing 400 g uncooked potato starch/kg and 100 g citrus pectin/kg. The potato starch-pectin (PSP) diet increased excretion of most amino acids by both caecectomized and intact hens compared with the cellulose diet, with this response being larger for intact hens. When compared across diets, caecectomized hens excreted more threonine and serine than intact hens.

3. Excreta voided by hens given PSP contained higher levels of alanine and valine and lower levels of aspartic acid, glutamic acid and methionine than excreta from the cellulose diet. When compared across diets, excreta from caecectomized hens contained more threonine, serine and isoleucine and less aspartic acid and alanine than excreta from intact hens.

4. Multiple regression analyses of excreta amino acid profiles on profiles of endogenous and microbial protein suggested that the intestinal microflora had greater influence on amino acids excreted by caecectomized hens than on those excreted by intact hens.
Iron availability from peas (Pisum sativurn) and bread containing added pea testa in rats
Authors: Fairweather-Tait Susan J. , Wright A. J. A.
Published: May 2005

1. Iron retention in adult male rats given 3 g dried ground peas, immature and mature (Pisum sarivum cv Dark-skin perfection) and leafless (Pisum sativum cv Filby), extrinsically labelled with 0.25 μCi 58Fe, was measured by whole-body counting. The Fe was less well absorbed (P < 0.01) from the mature peas (0.251 (SE 0.021)) than from the immature (0.384 (SE 0, 032)) or leafless peas (0.344 (SE 0.026)).

2. The availability of Fe from the leafless peas was compared with that of defatted soya-bean flour by the same technique. Significantly more Fe (P < 0.005) was retained from the pea flour (0.471 (SE 0.013)) than from the soya-bean flour (0.377 (SE 0.022)).

3. The effect of adding pea testa to bread (97.6 g/kg dry weight), as in the production of high-fibre white bread, on Fe availability was measured and compared with the availability of ferrous sulphate in young and adult male rats. There were no significant differences between the high-fibre and low-fibre breads in either age-group, although the older rats absorbed less Fe from all three sources. Retention from high-fibre bread, low-fibre bread and FeSO4 was as follows (mean with SE): young rats 0.452 (0.037), 0.475 (0.040) 0.541 (0.032); mature rats 0.363 (0.034), 0.366 (0.030), 0.471 (0.028).

4. It was concluded that the addition of pea testa to white bread does not have a detrimental effect on Fe availability. Immature and leafless peas appear to be a better source of available Fe than soya-bean flour, despite similar fibre levels, but with maturity the Fe in peas is rendered less available.
Selenium status in vegans and lactovegetarians
Authors: Åkesson B. , Öckerman P. A.
Published: May 2005

1. Plasma and urinary selenium were determined among vegans, lactovegetarians and several groups of omnivorous subjects, using gas-liquid chromatography.

2. Plasma Se was lower among lactovegetarians (0.80 (SD 0.18) μmol/l) than in the other groups (0.98 (SD 0.15) μmol/l). This was not related to Se intake, since the vegans had a lower and the lactovegetarians a higher intake of Se than omnivorous subjects in Sweden.

3. Urinary Se was 0.36 (SD 0.10)μmol/d for controls, 0.17 (SD 0.10) μmol/d for vegans and 0.16 (SD 0.07)μmol/d for lactovegetarians. No relation between dietary Se and urinary Se was observed. Among vegetarians, plasma Se and urinary Se were correlated (r0.51;P< 0.05).
The effects of dietary restriction and exercise on the volume of adipocytes in two intra-orbital depots in the guinea-pig
Authors: Mattacks Christine A. , Pond Caroline M.
Published: May 2005

1. The volume of adipocytes in two intra-orbital sites and fourteen superficial and intra-abdominal sites, and the total adipocyte complement have been measured in virgin and reproductive guinea-pigs maintained on several different regimens of diet and exercise.

2. The adipocytes around the ocular muscles at the back of the orbit (peripheral fat) are always larger than those just behind the eyeball (orbital fat).

3. The adipocytes in both the intra-orbital sites are significantly larger in guinea-pigs whose total adipocyte complement is smaller than one standard deviation from the mean, than in those which have a normal-size or large adipocyte complement.

4. The volume of intra-orbital adipocytes correlates very significantly with the volume of adipocytes in superficial and intra-abdominal sites in guinea-pigs which have large adipocyte complements, correlates weakly in those with normal adipocyte complements and not at all in those with small adipocyte complements.

5. It is suggested that there may be fewer intra-orbital adipocytes in animals which have small adipocyte complements, and that, because the intra-orbital adipose tissue occupies a constant volume, the adipocytes in these sites become larger when they are less numerous.
The effect of dietary guar gum on the activities of some key enzymes of carbohydrate and lipid metabolism in mouse liver
Authors: Stanley John C. , Newsholme Eric A.
Published: May 2005

1. The effects of a 100 g/kg substitution of guar gum on the body-weight gain, food consumption and faecal dry weight of mice fed on a high-sucrose diet and on the activities of hepatic glucose-6-phosphate dehydrogenase (EC 1. 1. 1. 49), 6-phosphogluconate dehydrogenase (EC 1. I. 1. 44), malate dehydrogenase (oxaloacetate- decarboxylating) (NADP+) (EC I. 1. 1. 40), ATP-citrate (pro-3S)-lyase (EC 4. I.3.8), 6-phosphofructokinase (EC 2.7. 1. 11), pyruvate kinase (EC 2. 7. 1. 40)and fructose-1, Qbisphosphatase (EC 3. 1. 3. 11) were studied.

2. Guar gum had no effect on body-weight gain or food consumption but increased faecal dry weight.

3. Guar gum increasedtheactivitiesofglucose-6-phosphatedehydrogenase, malatedehydrogenase(oxaloacetate- decarboxylating) (NADP+) and 6-phosphofructokinase expressed on a wet-liver-weight basis.

4. Guar gum increased the activities of glucose-6-phosphate dehydrogenase, malate dehydrogenase (oxaloacetate- decarboxylating)(NADP+), ATP-citrate (pro-3S)-lyase and 6-phosphofructokinase expressed on a liver-protein basis.

5. Guar gum increased the activities of glucose-6-phosphate dehydrogenase and malate dehydrogenase (oxaloacetate-decarboxylating)(NADP+) expressed on a body-weight basis.

6. These results suggest that guar gum increases the flux through some pathways of hepatic lipogenesis when mice are fed on high-sucrose diets.
Modifications in plasma cholesterol and apolipoproteins of hypercholesterolaemic rats induced by ethanol-soluble factors ofVicia faba
Authors: Mengheri Elena , Scarino M. Laura , Vignolini Francesco , Spadoni M. Antonietta
Published: May 2005

1. High-fat-high-cholesterol diets containing casein or aVicia faba bean(faba bean) protein concentrate as the protein source were given to rats for 5 weeks. When the faba bean protein concentrate or its ethanol extract was present in the diet, a marked decrease was found in the level of circulating cholesterol associated with the lower-density lipoproteins (very-low-, intermediate- and low-density lipoproteins) compared with the level found on the diets containing casein or the faba bean protein concentrate deprived of ethanol-soluble factors.

2. Alterations in apoprotein pattern were detected after the different dietary treatments. In particular, apoA-I appeared in an unusual form with electrophoretic mobility faster than normal in all lipoprotein fractions after feeding the diets that did not lower plasma cholesterol. When the diets contained the faba bean protein concentrate or its ethanol extract, the apoA-I disappeared from the lower-density lipoproteins but its normal form and the unusual one were apparent in the high-density lipoproteins.

3. A moderate increase in faecal excretion of acidic steroids was found after feeding the diets containing the ethanol-soluble factors, irrespective of the protein source.

4. The results are discussed in relation to the presence of saponin and polyunsaturated lecithin in the ethanol extract of the faba bean protein concentrate.
The effect of overfeeding newborn rabbits on the rate of skeletal maturation, as determined using a radiographic technique
Authors: Spencer S. Andrew , Small Philip G. , Hull David
Published: May 2005

1. Newborn rabbits were overfed by encouraging them to suck from two lactating does. These double-fed rabbits were compared with single-fed litter-mate controls.

2. A standard set of fore- and hind-foot radiographs was obtained by taking daily radiographs from a normal litter and selecting the most representative film to act as a standard for that day.

3. Bone age was assessed in single- and double-fed rabbits at ages 7, 14, and 21 d by comparing radiographs taken at these ages with the standard films.

4. Double-feeding was associated with an increase in body-weight and an increase in bone age, although the former was increased to a much greater extent than the latter. The advance in bone age was proportional to an increase in bone length.

5. There is little information available on overnutrition and skeletal maturation in man, but what information is available suggests that height and skeletal maturation are increased in parallel. The present study with rabbits supports the concept that overnutrition increases growth rate but does not disturb the relation hetween bone growth and bone age.

6. Bone age can be assessed very sensitively in rabbits using the previously-described technique. It would therefore be a valuable technique for studying the endocrinology of skeletal maturation.
What sort of teenager has low intakes of energy nutrients?
Authors: Woodward David R.
Published: May 2005

1. An alternative statistical technique, based on analysis of the 25th percentile, was used to examine teenagers' diets. The technique was developed to identify personal characteristics that affected the prevalence of low energy and nutrient intakes. It provided useful information not obtainable from methods based on average intakes.

2. The study sample was a representative sample of 1055 high-school students in Tasmania, Australia, aged 11–16 years.

3. Among girls, different characteristics had the greatest influence on the prevalence of low intakes (‘low’ being defined as below the 25th percentile for girls). Fatness had the greatest influence for several dietary components. Fatter girls were more likely to have low intakes of energy, carbohydrate, iron, calcium and niacin-equivalent, and also of ‘empty-energy’ foods. School type had the greatest influence for fat, riboflavin and vitamin A. Exercise had the greatest influence for protein, low intakes being more usual among the least active girls.

4. Among boys, height and age generally had the greatest influence on the prevalence of low intakes (‘low’ being defined as below the 25th percentile for boys). Taller and older boys were less likely to have low intakes. This was attributed partly to increased physiological needs, but peer-group influences appeared more important in relation to food choices. Thiamin was unusual, in that recent use of analgesics had the greatest influence on the prevalence of low intakes.
Studies on the energy metabolism of the pregnant sow
Authors: Noblet J. , Close W. H. , Heavens R. P. , Brown D.
Published: May 2005

1. Twenty-six gilts were used in an experiment to study the effects of level of feed intake on the growth and chemical composition of the gravid uterus and mammary tissue at several stages of gestation. The animals were given either 1.8 or 2.5 kg feed/d (20 or 30 MJ metabolizable energy (ME) respectively) and were slaughtered at intervals between days 40 and 110 of gestation. The gravid uterus was dissected into fetal, placental, fluid and empty uterus components. From day 70 of gestation the mammary tissue was also dissected. The fresh weight and dry matter (DM), energy and nitrogen contents of the various tissues were determined.

2. (a) With the exception of the fluid component, there was a significant increase (P < 0.01) in the fresh weight of each tissue with both stage of gestation and level of feeding. At comparable litter sizes the total weight of the fetuses in late gestation was 16% higher with the higher feed intake. (b) The DM content of the individual uterine tissues increased significantly (P < 0.01) with increase in stage of gestation so that the mean DM content of the gravid uterus increased from 74.6g/kg at day 50 to 103.1 and 159, 0g/kg at days 90 and 110 of gestation respectively. (c) Neither stage of gestation nor feeding level influenced the respective energy contents of the individual uterine tissues, when expressed per g DM. The mean energy content of the total gravid uterus was 19.5 kJ/g DM. (d) The N content (g/g fresh weight) of the tissues increased with stage of gestation and was generally higher at the higher feeding level. The mean N contents (g/g DM) of the fetal, placental, fluid and empty uterine tissues were 0.090, 0, 101, 0.098 and 0.128 respectively.

3. The mammary tissue was the most variable of all the tissues investigated. Whereas the fresh weight and N content increased with stage of gestation, both the DM and energy content decreased.

4. Gompertz equations were fitted to describe the effects of stage of gestation, level of feed intake and litter size on the fresh weight and chemical content of the individual uterine tissues, total gravid uterus and mammary tissue. The use of these equations for calculating the nutrient requirements of pregnancy is demonstrated.

5. It was calculated that between days 50 and 110 of gestation the ME requirement for reproduction increased from 3 to 12% of maternal energy intake. The calculated requirement for protein was from 7 to 41 % of maternal dietary protein intake respectively.