bluuebunny/crossref_metadata_2025 huggingface dataset:
Flow of nitrogen from the rumen and abomasum in cattle and sheep given protein-free nutrients by intragastric infusion
Authors: Ørskow E. R. , MacLeod N. A. , Kyle D. J.
Published: September 2005

1. Three experiments were conducted to determine the flow of nitrogen through the rumen and abomasum when cows, steers and lambs were totally nourished on volatile fatty acids infused into the rumen.

2. In two dairy cows (650–700 kg) and two large steers (370–405 kg) the daily flow of non-ammonia-N (NAN) from the rumen was 50.7 and 58 mg/kg live weight (W)0.75respectively.

3. The flows of NAN through the rumen and abomasum in four young steers (240 315 kg) were 85.0 (SE 21.0) and 195 (SE 7.0) mg/kg W0.75respectively.

4. In the third experiment the effects of altering rumen pH and osmotic pressure on flow of NAN through the rumen and abomasum were investigated in lambs. While rumen pH and osmotic pressure influenced rumen volume and outflow they had no significant effect on NAN flow. The mean values for NAN outflow from the rumen and abomasum were 76 and 181 mg N/kg W0.75respectively.

5. Abomasal NAN flow increased with increasing abomasal pH. When osmotic pressure was greater than about 330 mosmol/l in the rumen there was a net inflow of water, while below this value there was net loss of water.

6. For all experiments the flow of N both from the rumen and abomasum was highly variable; this has to be considered if a constant value is used for endogenous N in estimating dietary N in the abomasum.

7. With N-free infusion the rumen NHaconcentration varied from 50 to 120 mg NHa-N/I.

8. The amino acid composition of rumen and abomasal N was also determined. Relative to tissue Nit contained a higher proportion of cysteine.
Compensatory nitrogen retention in growing pigs following a period of N deprivation
Authors: Tullis J. Bronwyn , Whittemore C. T. , Phillips Patricia
Published: September 2005

1. Semi-synthetic diets, with dried microbial cells (Pruteen) as the nitrogen source, were used to measure N retention in 50 kg pigs given different combinations of N intake involving periods of deprivation and enhanced supply.

2. Metabolic faecal N losses were 1.92 g/d (1.26 g/kg dry matter eaten) and endogenous urinary losses were 3.96 g/d for pigs given an N intake of 6.9 g/d.

3. Compensatory N retention averaging 4.2 g extra N/d was observed in pigs given enhanced N supply by diets providing 31.0, 60.4 and 93.4 g N/d. In some instances enhanced N retention was maintained for 22 d.

4. Pigs given enhanced N supply by extravagant N intake did not maintain the compensatory response which had been evident initially.
The effect of manipulating growth in sheep by diet or anabolic agents on plasma cortisol and muscle glucocorticoid receptors
Authors: Sharpe P. M. , Buttery P. J. , Haynes N. B.
Published: September 2005

1. The cortisol status (total plasma cortisol concentration, free cortisol concentration, transcortin capacity) and the characteristics of skeletal muscle binding for cortisol and dexamethasone were examined in female lambs either implanted with Zeranol or trenbolone acetate or whose dietary intake was restricted.

2. The skeletal muscle glucocorticoid receptor had a high affinity for the glucocorticoid triamcinolone (relative binding affinity 0.85) and cortisol (relative binding affinity 0.51) with virtually no affinity for trenbolone.

3. Trenbolone acetate treatment reduced the binding capacity of sheep skeletal muscle for cortisol within 2 d of implantation. The other treatments had little effect except a small reduction in the animals where food intake was restricted. Similarly, binding capacity for dexamethasone was reduced by trenbolone acetate treatment but was not affected by the other treatments. This reduction in trenbolone acetate-treated animals is, at least in part, due to a reduction in glucocorticoid receptors.

4. Transcortin capacity was elevated by Zeranol treatment but reduced with diet restriction or trenbolone treatment.

5. No support for the suggestion of free cortisol concentration being important in the growth-promoting mechanism of trenbolone or Zeranol was obtained.

6. Although insulin concentrations were not significantly altered by treatment (P > 0.05), when combining all the animals there was evidence of a negative correlation between total cortiso1: insulin vaue (P < 0.05) or free cortisol: insulin value and growth rate (P < 0.001). Free cortisol was negatively correlated to growth rate (P < 0.05) and transcortin capacity positively correlated (P < 0.01).
Energy metabolism in healthy black Kenyan children
Authors: Duggan Maureen B. , Milner R. D. G.
Published: September 2005

1. Twenty-four healthy black Kenyan children, mean age 29 (SD 19) months, were studied over a 24 h period. Energy expenditure (EE) was determined using a ventilated-hood indirect calorimeter; measuring oxygen consumption and carbon dioxide production. Metabolizable energy intake was measured in twenty children. Anthropometric measurements were used to estimate surface area and lean body-weight.

2. The mean daily intake of metabolizable energy was 338.4 (se28.4) kJ/kg; 70% of gross dietary energy being provided by carbohydrate. The level of postprandial EE was significantly (P > 0.05) higher than the resting level (12.6 (se0.47) and 11.38 (se0.37) kJ/kg per h respectively) while the level of the postprandial respiratory quotient (RQ) was similar to the resting level (0.94 (se0.02)) and 0.98 (se0.03 respectively). In 33% of total observations of the resting RQ the value was more than 1.0. These findings suggest that short-term fat storage may be a normal feature of metabolism in children, and also that the energy cost of (postprandial) fat synthesis is increased by a high-carbohydrate diet.

3. Values for the resting metabolic rate and various estimators of body size were compared using regression analysis. It was evident that, in these young children with considerable variation in body composition, body-weight remained a satisfactory metabolic-size estimator.
The effect of protein and energy deficiency on skin glycosaminoglycan levels in the rat
Authors: Kaggwa Jane S. N.
Published: September 2005

1. The effects of protein-deficient and energy-deficient diets on the concentrations of skin glycosaminoglycans (GAGs) and collagen were studied in young rats.

2. In Expt 1, comparisons were made between animals fed on a control (C) diet (protein:energy (P:E) 0.210), a low-protein (LP) diet (P:E 0.032) and a very-low-protein (VLP) diet (P:E 0005)ad lib.Skin GAGS and collagen concentrations were determined at intervals as the animals became malnourished and when some of those fed on the VLP diet started showing signs of oedema. Concurrently, plasma albumin concentrations were determined to assess the extent of hypoalbuminaemia. With prolonged severe protein deficiency all GAGS species were reduced below normal levels. Collagen concentration decreased with prolonged protein deficiency. Protein-deficient rats developed hypoalbuminaemia.

3. In Expt 2, comparisons were made between animals fed on the C, LP and VLP dietsad lib.and others given the C diet in restricted amounts sufficient to maintain body-weights identical to those fed on LP or VLP dietsad lib.Energy-deficient rats, wasting at rates similar to protein-deficient ones, had higher skin GAGs concentrations than those in protein-deficient or control animals. With prolonged malnutrition, collagen concentrations were similar in protein- and energy-deficient animals and lower than those observed in control animals. Plasma albumin concentrations in energy-deficient animals were above starting values, except in severely energy-deficient animals at the end of the experiment. Protein-deficient animals developed hypoalbuminaemia.

4. In conclusion, the present study has shown that the main difference between prolonged severe protein deficiency and energy deficiency in the rat is that skin hyaluronic acid concentration is higher than normal in energy deficiency but below normal levels in prolonged severe protein deficiency. Initially skin collagen concentrations are higher than normal in both protein- and energy-deficient animals. However, with prolonged malnutrition the concentrations are reduced.
The effects of a high-animal- and a high-vegetable-protein diet on mineral balance and bowel function of young men
Authors: Dokkum W. Van , Wesstra Anneke , Luyken R. , Hermus R. J. J.
Published: September 2005

1. Twelve young men were given for periods of 20 d, each of three mixed diets, namely a low-protein (LP) diet (9% total energy as protein, 67% of animal origin), a high-animal-protein (HA) diet (16% total energy as protein, 67% of animal origin) and a high-vegetable-protein (HV) diet (16% total energy as protein, 67% of vegetable origin). Retention of calcium, magnesium, iron, zinc and copper as well as various bowel function indices were investigated during each dietary period.

2. Neither the HA diet nor the HV diet changed the retention of the minerals considerably. Only Fe balance decreased significantly on the HV diet.

3. Substituting the HV diet for the HA diet resulted in significant increases in faecal wet weight (17 g/d), defaecation frequency (0.12 stools/d), faecal volatile fatty acids (2.6 mmol/d) and a decrease in faecal bile acids (128 μmol/d).

4. It is concluded that a HV diet, rather than a HA diet is to be recommended with respect to bowel function, whereas the HV diet does not necessarily have a significant influence on mineral retention.
The effect of oral contraceptives on the apparent vitamin B6status in some Sudanese women
Authors: Salih Eltayeb Y. , Zein Asma A. , Bayoumi Riad A.
Published: September 2005

1. In vitro activation of erythrocyte aspartate aminotransferase (EC2.6.1.1) activity by pyridoxal phosphate was used to assess vitamin B4nutritional status in forty Sudanese women taking combined, low-dose oral contraceptives (oestrogen-progestogen; OC) and in thirty healthy, non-pregnant women not taking OC.

2. Fourteen (35%) out of forty OC users showed apparent vitamin B4deficiency.

3. Side-effects associated with OC were more common among the apparently vitamin-B4-deficient OC users than among OC users and non-OC users not deficient in vitamin B4.
Abnormal fermentations in continuous cultures of rumen microorganisms given cobalt-deficient hay or barley as the food substrate
Authors: McDonald P. , Suttle N. F.
Published: September 2005

1. Four experiments, each with four concurrent continuous cultures of rumen micro-organisms, were used to investigate the effects of inoculum, food substrate and cobalt supplementation on the course of fermentation and vitamin B12synthesis. The inocula came from sheep receiving either a Co-rich, complete diet (Ruminant A: Expts 1, 2 and 4) or a Co-deficient hay (Expt 3). In Expt 2, inocula from different donors were used for each culture but for other experiments they were pooled. Co-deficient hay was used as the initial substrate and Co-supplements were given after 8–54 d Co-depletion.

2. In three of four experiments, two using a pooled inoculum, uncharacteristically low acetate (Ac) and high propionate (Pr) outputs were obtained from the hay substrate in some cultures. In all, six cultures gave Ac:Pr values in the effluent > 2: 1 and, in Expt 3, the differences remained evident for at least 6 d after a change to a Co-deficient barley substrate.

3. Abnormal cultures gave lower cobalamin (cbl) and vitamin B12analogue outputs than normal cultures: when supplemented with Co they showed small responses in cbl and large responses in analogue output with a slow increase in Ac:Pr.

4. We suggest that the use of Co-deficient substrates led to shifts in the microbial populations of some cultures, indicating the cbl-dependence of some species of rumen micro-organisms.
Effects of intraruminal sodium chloride infusion on rumen and renal nitrogen and electrolyte dynamics in sheep
Authors: Godwin Ian R. , Williams Vernon J.
Published: September 2005

1. Sheep were given 800 g low-protein roughage/d at 2 h intervals and infused intraruminally with 0, 500, 750, 1000, 1250, 1500 or 2000 mmol sodium chloride/d in 436 ml water. The digestibility of various food fractions and rumen ammonia, volatile fatty acids (VFA) and liquid turnover rate were measured, along with renal haemodynamics and the renal excretory patterns of nitrogen and electrolytes. Ad lib. food intake was determined during the infusion of 0 and 2000 mmol NaCl/d.

2. Infusion of NaCl up to 750 mmol/d had virtually no effect on the indices measured, except water intake and water excretion. Infusion of greater amounts caused a step-wise decrease in the digestibility of organic matter (OM) and N. Rumen liquid turnover rate was increased substantially and rumen NH2, and VFA concentrations were decreased. Ad lib. food intake was not different when either 0 or 2000 mmol NaCl/d were infused into the rumen.

3. The glomerular filtration rate and effective renal plasma flow (ERPF) were substantially increased after the infusion of 1250 mmol or more NaCl/d. Extracellular fluid volume was also increased. The renal excretion of urea and uric acid+allantoin (URAL) were decreased at the higher infusion rates but the fractional excretions of both these substances were enhanced. The excretion of sodium, chloride, calcium and magnesium were markedly increased with increasing salt infusion.

4. The results suggest that high NaCl inputs into the rumen increase the rumen turnover rate, which in turn decreases the digestibility of OM, particularly N. This causes lower rumen NH3, and VFA concentrations. Plasma urea and URAL concentrations are also decreased and this causes lower renal excretion of these substances despite a much higher fractional excretion resulting from the greatly enhanced urine flow rate.

5. When roughages low in N are given, NaCl intake should be kept below 20 mmol/kg body-weight per d to prevent a decline in the digestibility of the food and any consequent reduction in protein available to the sheep.
Role of rumen protozoa in nitrogen digestion in sheep given two isonitrogenous diets
Authors: Ushida K. , Jouany J. P. , Thivend P.
Published: September 2005

1. The effect of protozoa on digestion in the rumen was studied using either defaunated or faunated sheep.

2. Six wethers, each fitted with rumen and simple duodenal cannulas, were given two isonitrogenous diets containing either lucerne (Medicago sativa) hay (diet L) or sodium hydroxide-treated wheat straw (diet S). The diets were given in eight equal portions per day at 3-h intervals. The mean intake of dry matter, 53 g/kg body-weight0.75per d, was similar for the two diets and each diet had a similar digestible organic matter content. Diet L promoted a large protozoal population and was rich in nitrogen sources of low rumen-degradability, while diet S supported a smaller protozoal population and was rich in rumen-degradable N.

3. Digesta flow at the duodenum was estimated by means of a dual-marker technique using chromium-mordanted lucerne hay and polyethylene glycol as markers. The microbial flow at the duodenum was estimated using diaminopimelic acid (DAPA), nucleic-acid purine bases (PB) and35S incorporation simultaneously. The different microbial markers were compared in the defaunated sheep. Protozoal N contribution was estimated in faunated sheep.

4. Defaunated sheep had lower rumen ammonia concentrations and molar proportions of butyric acid than faunated sheep, but they had higher molar proportions of propionic acid.

5. Rumen organic matter digestion was reduced by defaunation, but this decrease was compensated for by increased intestinal digestion.

6. There was a net increase of N flow (approximately 10 g/d) between mouth and duodenum in defaunated sheep. This was explained by increases in both microbial and dietary N flows from the rumen compared with faunated sheep.

7. The influence of protozoa on solid- and liquid-phase retention times in the rumen is discussed, as well as the protozoal contribution to microbial N flow in the duodenum of faunated sheep.
Dynamics of large ciliate protozoa in the rumen of cattle fed on diets of freshly cut grass
Authors: Leng R. A. , Dellow D. , Waghorn G.
Published: September 2005

1. The dynamics of large ciliate (holotrich) protozoa (Isotricha and Dasytricha spp.) in the rumen of cattle given cut, fresh ryegrass (Lolium multiflorium Lam) were studied by means of a single intrarumen injection of14C-labelled protozoa prepared in vitro by adding [Me14C]choline to rurnen fluid containing protozoa and incubating at 39° for 2 h.

2. An indication of the lysis rate of protozoa in the rumen was obtained from the radioactivity apparently lost through the methane pool.

3. The turnover time of the holotrich protozoa indicates that these protozoa were extensively retained in the rumen and that only a small proportion of those produced in the rumen flowed out in the digesta. This was supported by the estimation of the rate of lysis which was approximately 85% of the turnover rate in the rurnen.

4. The apparent production rate of the larger protozoa indicates that they contribute only about 9% of the predicted net microbial protein synthesis in the rumen.
The effect of digestibility and forage species on the removal of digesta from the rumen and the voluntary intake of hay by sheep
Authors: Aitchison E. M. , Gill M. , Dhanoa M. S. , Osbourn D. F.
Published: September 2005

1. The characteristics of digestion, passage and rumen fill of three hays: early- and late-cut perennial ryegrass (Loliurn perenne cv. Endura) and white clover hay (Trifolium repens cv. Blanca and Pronitro) were studied using six rumen-cannulated sheep fed at a restricted level of intake (18 g dry matter (DM)/kg live weight (LW) per d), in a two 3 x 3 Latin square design.

2. Voluntary intake of the same diets was measured using a further six non-cannulated sheep in a similar design.

3. Rate of digestion of the three hays was measured using dacron bags and the rates of digestion of DM and neutral-detergent fibre (NDF) for clover hay were significantly (P < 0.05 and P < 0.001 respectively) faster than those for the two grass hays whose rates did not differ. Rates of passage, determined using chromium-mordanted hay, did not differ between treatments.

4. Rumen pool sizes of DM, organic matter and fibre were generally greatest for the late-cut grass hay and lowest for the clover hay, while voluntary intake was highest (P < 0.001) for the clover hay (36.6 g DM/kg LW per d) and lowest for the late-cut grass hay (24.7 g/kg LW per d).

5. The net rate of removal of indigestible fibre from the rumen appeared to vary within the day, with maximal disappearance occurring during eating, followed by a lag phase between 5 and 10 h after feeding, with a second increase in rate between 10 and 24 h post-feeding.
The effect of supplementation with maize starch and level of intake of perennial ryegrass (Lolium perenne cv. Endura) hay on the removal of digesta from the rumen of sheep
Authors: Aitchison E. M. , Gill M. , Osbourb D. F.
Published: September 2005

1. Eight wether sheep were offered a diet of perennial ryeigrass (Litum perenne cv. Endura) hay once daily at two levels of intake (11 and 16.5 g dry matter (DM)/kg live weight (LW)) with or without maize starch (175 g DM/kg hay DM). The experiment consisted of four periods. each lasting 32 d. Rates of digestion of the hay were measured by incubation in dacron bags and rates of passagc using chromium-mordanted hay. Rumen pool sizes of DM, organic matter and fibre were measured by emptying the rumen.

2. The inclusion of starch in the diet appeared to increase significantly (P < 0.01) the lag phase before the start of fibre digestion, as observed both in the dacron bag studies and in the slower initial disappearance of digestible neutral-detergent fibre (NDF) from the rumen recorded by emptying of rumen contents. However, there was no significant effect of starch on apparent digestibility of fibre in the whole tract.

3. The main effect of increasing the level of feeding wax, to increase the rate of passage with a consequent decrease in overall digestibility. The fractional rate of passage increased from 0.0318 to 0.0400 as the level of feeding increased, while apparent digestibility of NDF decreased from 0.755 to 0.724.

4. On all treatments the weight of indigestible fibre in the rumen remained more or less constant between 5, 10 and 15 h after feeding, but was significantly lower at 24 h. These results suggest that a high proportion of the outflow of material from the rumen not associated with feeding appears to occur during the second half of the feeding cycle.
Effects of supplements on intake, rumen function and nutrient supply and growth in cattle eating alkali-treated oat straw
Authors: Spragg J. C. , Kellaway R. C. , Leibholz Jane
Published: September 2005

1. Expt 1. Six 200 kg Hereford heifers fitted with rumen and abomasal cannulas were fed adlib. on alkali-treated oat straw sprayed with urea and minerals, with no supplement (O), or 700 g rolled barley (B) or cottonseed meal (C)/d, in a 3 x 3 Latin square with two replicates.

2. Intakes of the basal diet were not significantly affected by the supplements. Intakes of digestible organic matter (OM) were 3135, 3325 and 3515 g/d on diets O, Bland C respectively. Abomasal OM flow on diet C was 13 and 12% higher than on diets O and B respectively (P < 0.05) which was associated with a decrease in the proportion of OM intake apparently digested in the rumen ( P < 0.05) and an increase in the proportion of abomasal OM digested in the lower gut ( P < 0.05).

3. Total nitrogen and bacterial N flows at the abomasum were significantly higher (P < 0.01 and P < 0.05 respectively) on diet C than on diets O and B. Efficiency of bacterial N synthesis on diet C was 19 and 28% higher than on diets 0 and B respectively ( P < 0.05).

4. Dry matter (DM) pool size in the rumen was greater on diet C than on diets O and B (P < 0.05).

5. Expt 2. Thirty-three 210 kg Friesian heifers were allocated to the same treatments as in Expt I. Intakes of the basal straw diet were not significantly affected by the supplements. Intakes of digestible OM were 3.80, 4.16 and 4.34 kg/d on diets O, B and C respectively.

6. Rumen ammonia and plasma urea levels were significantly higher on diet C than on diets O and B ( P < 0.05).

7. Live-weight gains were 679, 838 and 1051 g/d on diets O, B and C respectively ( P < 0.01) and live-weight gain/MJ metabolizable energy intake was highest on diet C (P < 0.01).

8. It was concluded that the growth response to barley was attributable to the increase in energy supply, and that the additional response to cottonseed meal was attributable to greater protein absorption arising from greater abomasal flows of bacterial and dietary proteins.
Kinetics of nitrogen transfer across the rumen wall of sheep given a low-protein roughage
Authors: Neutze S. A. , Kellaway R. C. , Faichney G. J.
Published: September 2005

1. The significance of blood urea-nitrogen transfer to the rumen was examined in sheep given alkali-treated wheat straw supplemented with 3.5 (diet A), 5.9 (diet B) and 11.6 (diet C) g urea-N/kg dry matter (DM).

2. Mean voluntary intakes of DM (g/d) were 897, 1149 and 1225 for diets A, B and C respectively, indicating significant (P < 0.05) intake responses to urea supplementation. Digestion studies were conducted at 90% of voluntary intake. Dietary N intakes (g/d) were 7.1, 11.5 and 18.6 for diets A, B and C respectively.

3. Absorption of ammonia-N from the rumen (g/d) was 3.5, 6.7 and 8.9 for diets A, B and C respectively, with all dietary differences being significantly different (P < 0.05).

4. Non-ammonia-N (NAN) leaving the abomasum (g/d) was 9.6, 12.7 and 14.8 for diets A, B and C respectively. Microbial N leaving the abomdsum (g/d) was 6.8, 9.6 and 10.7 for diets A, B and C respectively. Hence, significantly (P < 0.05) more N was provided to the intestines with increased urea supplementation. Net efficiencies of microbial protein synthesis (g N/kg organic matter apparently digested in the rumen), estimated from 16N incorporation, were 24.2, 23.7 and 25.3 for diets A, B and C respectively, and were not significantly different (P > 0.05).

5. Calculated proportions of microbial N derived from rumen NH2-N were 1.05, 0.95 and 0.91 for diets A, B and C respectively, reflecting the high proportion of total N as urea-N in the diets. Proportions of microbial N derived from blood urea-N were 0.31, 0.21 and 0.12 for diets A, B and C respectively, indicating a decreasing significance of blood urea as a source of microbial N as dietary urea increased (P < 0.05).

6. Transfer of blood urea-N to the rumen (g/d) was 3.8, 4.7 and 2.6 for diets A, B and C respectively, being significantly (P < 0.05) lower on diet C. Using an estimate, of the salivary contribution of urea-N to the rumen, it was concluded that there was a significant though not large transfer of blood urea-N across the rumen wall on all diets.

7. Net transfer of blood urea-N to the rumen was estimated from a two-pool model and was +0.4 g/d for diet A, though this was not significantly different from zero. Net transfers for diets B and C were -2.0 and - 6.3 g N/d respectively.

8. Significant intake responses to exogenous urea supplementation were observed because of a limited capacity to recycle N to the rumen under the conditions of low dietary N supply imposed.
Comparative studies on the hypercholesterolaemia induced by excess dietary tyrosine or polychlorinated biphenyls in rats
Authors: Nagaoka Sahoshi , Kato Mitsuhiro , Aoyama Yoritaka , Yoshida† Akira
Published: September 2005

1. The effects of dietary polychlorinated biphenyls (PCB) and excess tyrosine on serum and liver lipids, urinary ascorbic acid and catecholamines were compared in male Wistar rats.

2. Serum levels of cholesterol, urinary ascorbic acid, norepinephrine, epinephrine, dopamine and histamine were significantly increased in rats given either PCB or excess tyrosine.

3. The hypercholesterolaemia induced by PCB or excess tyrosine was blocked by the adrenergic α-blocker, phenoxybenzamine.

4. The present results suggest causal interrelations between the hypercholesterolaemia induced by dietary PCB or excess tyrosine and the secretion of catecholamines.
The influence of guar-gum bread on the regulation of diabetes mellitus type II in elderly patients
Authors: Sels J. P. , Flendrig J. A , Postmes Th. J.
Published: September 2005

1. The effect of a high-fibre bread mixed with guar-gum (75 g/kg flour) on serum glucose, connecting peptide (C-peptide), haemoglobin A1 (HbAI), high-density-lipoprotein-cholesterol (HDL-cholesterol) and triglycerides was examined in fourteen elderly patients with diabetes mellitus type II.

2. The mean daily consumption of guar gum was 8.1 g. Gastrointestinal disorders were not observed.

3. Consumption of guar-gum bread resulted in a significant decrease in C-peptide values on the 1st day and blood glucose values after 3 weeks (both measured 90 min after breakfast). C-peptide values remained low, while an unaccountable ‘rebound’ phenomenon was seen in the blood glucose values 90 min after breakfast at the end of the study.

4. No significant change was seen in respect to HDL-cholesterol and triglycerides. However, a small significant increase in HbAl was noted.
Nutritional anaemia in pregnant Beninese women: consequences on the haematological profile of the newborn
Authors: Hercberg Serge , GalÁn Pilar , Chauliac Michel , Masse-Raimbault Anne-Marie , Devanlay Michel , Bileoma Semiou , Alihonou Eusebe , Zohoun Isidore , Christides Jean-Philippe , De Courcy Geneviève Potier
Published: September 2005

1. An assessment of iron and folic acid status, blood thick film and haemoglobin (Hb) electrophoresis was performed on 126 pregnant women (and their newborn infants) and in ninety-five menstruating women in Cotonou (Benin).

2. Anaemia (according to the World Health Organization (1972)) was observed in 55% of pregnant women and in 39% of menstruating women.

3. Fe-deficiency was defined as a low serum ferritin concentration (12μg/l or less), combined with a low transferrin saturation (less than 16%) or a high erythrocyte protoporphyrin level (more than 3 μg/g Hb), or both. A moderate elevation in the serum ferritin concentration (between 13 and 50 μg/l), associated with a low transferrin saturation or a high erythrocyte protoporphyrin level, or both, indicated Fe-deficiency in an inflammatory context. Fe-deficiency was present in 73% of pregnant women and in 41% of menstruating women.

4. Folate deficiency (defined as erythrocyte folate below 160 μg/l) was observed in 45% of pregnant women.

5. In pregnant women, anaemia was associated with Fe-deficiency in 83% of cases and with folate deficiency in 48% of cases.

6. Haemoglobinopathies were mainly heterozygous and did not seem to contribute significantly to anaemia. Intensity of malaria was not related to Hb level, butPlasmodium falcipurumwas found in 99% of subjects.

7. Hb concentration and mean corpuscular volume were significantly lower in babies born of Fe-deficient mothers than in babies born of Fe-sufficient mothers. Hb concentration in newborn infants was positively correlated with maternal serum ferritin.
Lactitol, a new hydrogenated lactose derivative: intestinal absorption and laxative threshold in normal human subjects
Authors: Patil Dharmaraj H. , Grimble George K. , Silk David B. A.
Published: September 2005

1. In the first part of the study, the absorption of lactitol, a new disaccharide analogue of lactose, was studied using an in vivo jejunal perfusion technique in man. Intestinal uptake of lactitol from isotonic solutions containing 10, 30, 60, and 100 mmol lactitol/l was insignificant.

2. In the second part of the study the laxative threshold of lactitol was determined and compared with that of sorbitol in a double-blind, randomized, cross-over study on twenty-one normal subjects. Laxative threshold was considered to be either the maximum dose tolerated without unacceptable diarrhoea or gastrointestinal side effects, or when the maximum dose in the study was reached. Increasing amounts of lactitol, sorbitol or placebo were administered in two divided doses each day until subjects developed diarrhoea or severe gastrointestinal side effects. The laxative threshold of lactitol (74 (SE 5) g/d) was similar to that of sorbitol (71 (SE 5) g/d).

3. These findings indicate that lactitol is not absorbed by the human small intestine. Although diarrhoea or other gastrointestinal side effects occurred as the dose was increased, 40 g lactitol/d was well tolerated.
Reproducibility of 24 h energy expenditure measurements using a human whole body indirect calorimeter
Authors: De Boer Janna O. , Van Es Aren J. H. , Vogt Joop E. , Van Raaij Joop M. A. , Hautvast Joseph G. A. J.
Published: September 2005

1. Ten female subjects completed two similar experimental procedures (periods 1 and 2) to obtain values of reproducibility of energy intake and 24 h energy expenditure (24hEE) measurements in a whole body indirect calorimeter. The periods consisted of consumption of a provided weight-maintenance diet for 6–8 d, faeces and urine collection during the last 4 d and occupation of the calorimeter during the last 3 d. The daily routine inside the calorimeter simulated a sedentary day in normal life with some physical activity: 8 h sleep, 75 min bicycling and the remaining time spent on sedentary activities. The metabolizable energy (ME) content of the diet (14% energy as protein, 46% energy as carbohydrate, 40% energy as fat) was calculated using food tables. The actual ME intake as well as digestibility and metabolizability of the diet were obtained later by analyses of food, faeces and urine for energy. Three consecutive 24hEE measurements were performed during the stay in the calorimeter in each period. The time interval between the two periods varied from 2 to 24 months. Reproducibility was assessed at group and individual level.

2. Mean digestibility and metabolizability of the diet showed no significant difference between periods. The within-subject coefficient of variation of metabolizability between periods was 1.7%.

3. Mean 24hEE (MJ) over 3 d did not differ between period 1 (8.78 (SD 0.63)) and period 2 (8.73 (SD 0.66)). The within-subject coefficient of variation in mean 24hEE over three successive days between periods was 3.1% but decreased, after deletion of values for subjects who were less adapted to the calorimeter, to 1.9%.

4. The results are discussed with regard to length of trial and the number of subjects required to test a difference in energy metabolism using whole body indirect calorimeters.
Nitrogen balance studies in apparently healthy elderly people and those who are housebound
Authors: Bunker Valda W. , Lawson Margaret S. , Stansfield Maureen F. , Clayton Barbara E.
Published: September 2005

1. Metabolic balance studies (5 d) for nitrogen were carried out in twenty-four apparently healthy elderly people (age 69.7–85.6 years) and a heterogeneous group of twenty housebound elderly people (age 69.9–85.1 years) with chronic diseases. During the study all subjects ate self-selected diets, lived in their own homes and continued their normal daily activities. Seven of the housebound received meals-on-wheels 5 d/week.

2. Healthy men and women had mean metabolizable energy intakes of 8.7 and 6.6 MJ/d respectively compared with 6.3 and 4.8 MJ/d in the housebound. The average energy content of the meals-on-wheels as delivered was 2.4 MJ per meal, of which 2.1 MJ were consumed.

3. The healthy men and women had average daily protein intakes of 69.4 and 59.7 g respectively compared with 46.3 and 39.1 g in the housebound. Meals-on-wheels as supplied provided 19.4 g protein per meal, of which 16.2 g were consumed.

4. Healthy subjects were in equilibrium for N balance (0 mmol/d) with a daily intake of 733 mmol, which was equivalent to 11.04 mmol N (0.97 g mixed protein)/kg body-weight per d. Housebound individuals were in negative N balance (–95 mmol/d) with an intake of 475 mmol/d, corresponding to 7.59 mmol N (0.67 g mixed protein)/kg body-weight per d.

5. We were unable to determine in the present study whether the negative N balance observed in the housebound people was due to the relatively low N intake or the underlying disease condition.
The metabolizable energy value of Polydextrose® in a mixed diet fed to rats
Authors: Cooley S. , Livesey G.
Published: September 2005

1. The digestible energy (DE) and metabolizable energy (ME) values of a commercial Polydextrose® product and the polymer that it contained were determined by metabolic energy balance in male Wistar rats and compared with values obtained by radiochemical balance using a radiochemical analogue. The energy values of the whole preparations and of the polymer fractions were estimated.

2. In the energy-balance study of 6 d duration, 100 g maize starch/kg control diet were replaced by Polydextrose® to provide a test diet. Polydextrose® had no significant effects on food intake, body-weight gain, digestibility of nitrogen and N retention but significantly increased the water consumption to 143% of the control value (P < 0.05) and the water content of fresh faecal pellets from 548 (SE 10) to 646 (SE 15) g/kg wet weight (P < 0.01).

3. By energy balance the DE in the Polydextrose® product and in the polymer that it contained were 13.5 and 12.8 (SE 1.9) kJ/g respectively. The corresponding ME values were 12.7 and 12.1 (SE 1.8) kJ/g respectively. These values were higher (P < 0.05) than the corresponding values obtained by the radiochemical balance procedure: DE 8.8 and 8.6 (SE 0.4) kJ/g polymer respectively and ME 8.0 and 7.8 (SE 0.5)kJ/g polymer respectively.

4. These findings indicate relatively high energy values for Polydextrose® by comparison with previously published values and illustrate a potential difficulty when using energy values obtained by certain radiochemical methods to estimate the energy values of a mixed diet given to rats. Several alternative explanations of the discrepancies are advanced.
Vitamin-A-dependent zinc-binding protein and intestinal absorption of Zn in chicks
Authors: Berzin Nadezhda I. , Bauman Victoria K.
Published: September 2005

1. It was demonstrated that the development of experimental avitaminosis A in chicks led to secondary zinc deficiency. The balance of Zn in the chick became negative, while the Zn content of various tissues decreased. Thus in vitamin-A-deficient chicks the serum Zn content was 1258 (SD 26.3) μg/l which was considerably lower than 1652 (SD 97.8) μg/l in controls.

2. Zn absorption was considerably reduced throughout the entire small intestine of vitamin-A-deficient chicks and most markedly in the ileal region. Within 72 h after retinyl acetate administration Zn absorption was fully restored in this region of the intestine.

3. The65Zn-binding capacity of soluble proteins, present in the supernatant fraction of ileal-mucosa homogenates of vitamin-A-deficient chicks, was found to increase 2.6 times by 72 h after the administration of a single dose of retinyl acetate.

4. A vitamin-A-dependent Zn-binding protein (ZnBP), absent in vitamin-A-deficient chicks, was isolated from the ileal mucosa after their repletion with vitamin A. Competitive-binding studies (calcium, cadmium, copper) showed the protein to be highly specific for Zn ions.

5. The molecular weight of ZnBP wa5 83 kDa. The association constant of the protein-Zn complex was 0.8 x 106/mol. The protein was acidic with approximately 20% of its amino acid residues belonging to dicarboxylic acids. ZnBP was found to be a glycoprotein, and it contained hexose as a carbohydrate component.

6. It is suggested that ZnBP is involved in the binding of Zn in the ileal mucosa of chicks.
Food intake and energy expenditure of Nigerian female students
Authors: Cole A. H. , Ogungbe R. F.
Published: September 2005

1. Twenty apparently healthy and normal Nigerian female students, resident at the University of Ibadan campus, were studied for seven consecutive days to assess their food energy intake and energy expenditure during sedentary and physical activities.

2. The mean age (years) of the group was 20.05 (SD 3.44, range 16–29), mean height (m) 1.62 (SD 0.07, range 1.47–1.74) and body-weight (kg) 51.28 (SD 3.21, range 46–58).

3. The food intake of each subject was obtained by direct weighing, and the energy value determined using a ballistic bomb calorimeter. Daily activities were recorded and the energy cost of representative activities was determined by indirect calorimetry.

4. Activities mainly involved sitting, mean (min/d) 354 (SD 84, range 253–475). Personal domestic activities took a mean of 162 (SD 73) min/d. Sleeping took a mean of 451 (SD 62) min/d.

5. The mean energy intake of the group was 8480 (SD 1316) kJ/d or 167 (SD 30.6) kJ/kg body-weight per d. This value is lower than that recommended by the Food and Agriculture Organization/World Health Organization (FAO/WHO) (1973) as the energy requirement for adult women engaged in light activities (9205 kJ/d), but it is higher than the FAO/WHO/United Nations University (UNU) (1985) recommended value of 8326 kJ (1990 kcal)/d for a housewife in an affluent society. It is lower than the recommended intake of 9350 kJ/d for rural women in developing countries (FAO/WHO/UNU, 1985).

6. The mean energy expenditure (kJ/d) of the female subjects was 6865 (SD 214, range 6519–7222). Mean energy expenditure was lower than mean energy intake.

7. The energy intake and expenditure values indicated that the subjects participating in the present study were not physically very active. It is suggested, for health reasons, that they might undertake more physical activity.
The effects of fruit juices and fruits on the absorption of iron from a rice meal
Authors: Ballot D. , Baynes R. D. , Bothwell T. H. , Gillooly M. , Macfarlane J. , Macphail A. P. , Lyons G. , Derman D. P. , Bezwoda W. R. , Torrance J. D. , Bothwell J. E.
Published: September 2005

1. The effects of the chemical composition of fruit juices and fruit on the absorption of iron from a rice (Oryza sativa) meal were measured in 234 parous Indian women, using the erythrocyte utilization of radioactive Fe method.

2. The corrected geometric mean Fe absorptions with different juices varied between 0.040 and 0.129, with the variation correlating closely with the ascorbic acid contents of the juices (rs 0.838, P < 0.01).

3. Ascorbic acid was not the only organic acid responsible for the promoting effects of citrus fruit juices on Fe absorption. Fe absorption from laboratory ‘orange juice’ (100 ml water, 33 mg ascorbic acid and 750 mg citric acid) was significantly better than that from 100 ml water and 33 mg ascorbic acid alone (0.097 and 0.059 respectively), while Fe absorption from 100 ml orange juice (28 mg ascorbic acid) was better than that from 100 ml water containing the same amount of ascorbic acid (0.139 and 0.098 respectively). Finally, Fe absorption from laboratory ‘lemon juice’ (100 ml orange juice and 4 g citric acid) was significantly better than that from 100 ml orange juice (0.226 and 0,166 respectively).

4. The corrected geometric mean Fe absorption from the rice meal was 0.025. Several fruits had little or no effect on Fe absorption from the meal (0.013–0.024). These included grape (Vitis vinifera), peach (Prunuspersica), apple (Malus sylvestris) and avocado pear (Persea americana). Fruit with a mild to moderate enhancing effect on Fe absorption (0.03 1–0.088) included strawberry (Fragaria sp.) (uncorrected values), plum (Prunus domestica), rhubarb (Rheum rhaponticum), banana (Musa cavendishii), mango (Mangifera indica), pear (Pyrus cornmunis), cantaloup (Cucumis melo) and pineapple (Ananas comosus) (uncorrected values). Guava (Psidium guajava) and pawpaw (Carica papaya) markedly increased Fe absorption (0.126–0.293).

5. There was a close correlation between Fe absorption and the ascorbic acid content of the fruits tested (rs 0.738, P < 0.0001). There was also a weaker but significant correlation with the citric acid content (rs 0.55, P < 0.03). Although this may have reflected a direct effect of citric acid on Fe absorption, it should be noted that fruits containing citric acid also contained ascorbic acid (rs 0.70, P < 0.002). Similarly, the negative correlation (rs –0.62, P < 0,008) between Fe absorption and the malic acid content of fruits may have been due to the fact that fruits with a high malic acid content tended to have low levels of ascorbic acid (rs–0.45, P < 0.06).

6. These various results suggested that most fruits have only a limited effect on overall Fe nutrition. However, the presence of citrus fruit, guava or pawpaw would be expected to increase Fe absorption markedly from diets of low Fe availability.
Origin and utilization of volatile fatty acids and lactate in the rabbit: influence of the faecal excretion pattern
Authors: Vernay Michéle
Published: September 2005

1. Interrelations between bacterial metabolites (volatile fatty acids, lactate) in the gut contents and the blood in relation to the faecal excretory cycle (soft or hard faeces) were studied in anaesthetized rabbits.

2. It appeared that the level of organic acids in the alimentary tract varied cyclicly with the faecal excretion pattern. The lactate entering the portal circulation originates from the stomach, while the volatile fatty acids (VFA) originate from the hind-gut. Net absorption from the digestive tract and hepatic utilization of fermentation acids were greater when the rabbits produced hard faeces (hard-phase) compared with soft faeces (soft-phase). Propionate and butyrate reaching the liver were almost quantitatively removed; acetate and lactate were available for extra-hepatic tissue metabolism.

3. Whatever the excretion pattern the levels of VFA in the arterial circulation remained remarkably constant; blood lactate, however, was lower during the soft-phase.

4. Absorption of bacterial metabolites, like their metabolism in the liver, showed a circadian rhythm parallel to the changes in the activity of the adrenal glands, i.e. the activity was enhanced during the hard-phase.
Use of particle-bound microbial enzyme activity to predict the rate and extent of fibre degradation in the rumen
Authors: Silva Ayona T. , Wallace R. J. , Ørskov E. R.
Published: September 2005

1. A method was developed for extracting enzymes from micro-organisms closely associated with ammoniatreated straw (NH3-S) that had been incubated in nylon bags in the rumen. Incubation of washed straw with 125 ml carbon tetrachloride/l and 20 μg lysozyme/ml for 3 h at 37° gave carboxymethylcellulase (EC3. 2. 1. 4; CMCase) and NAD-linked glutamate dehydrogenase (EC1. 4. 1.2; GDH) activities greater than those extracted by sonication.

2. GDH associated with NH3-S increased with incubation time and was highest in sheep receiving a high-barley diet. Particle-bound CMCase activity reached a peak between 16 and 24 h and declined thereafter.

3. Particle-bound GDH activity showed no correlation with dry matter (DM) degradation in the rumens of sheep fed on a range of diets. In contrast, CMCase activity after 24 h was highly correlated with DM degradability of the same samples at 24 h (r0.98) and 48 h (r0.94).

4. It was concluded that GDH and CMCase can be used as indices of the total population of colonizing rumen micro-organisms and of the fibre-degrading population respectively, and that these enzymes can therefore be used to assess rapidly and with great sensitivity variations in the rumen environment that affect the rate of fibre breakdown.
Effects of sodium intake during two parities on Na status in Blackface sheep
Authors: Vincent Isobel C. , Michell A. R. , Williams H. Ll. , Hill R.
Published: September 2005

1. A low-sodium diet was given to Blackface ewes over two reproductive seasons. This diet provided a total of 3–7 mmol/d except during lactation when the intake was about 11 mmol/d. Control ewes were given the same diet supplemented with sodium chloride to provide recommended levels which were about tenfold that of the experimental diet.

2. The output of Na in urine and faeces from ewes given the low-Na diet was very low, about 3 mmol/d, from early in the experiment and continued at about this level throughout.

3. Lambs born to low-Na ewes and given a low-Na diet similar to that of their dams during lactation, grew, after weaning, more slowly than corresponding lambs from control ewes, but at 6 months of age when six from each group were killed, tissue Na contents were only slightly lower in experimental than control lambs.

4. Fluids and tissues obtained at the end of the second lactation from four ewes of each group that had suckled twin lambs, were analysed for Na and potassium. The Na concentration in saliva and rumen fluid of low-Na ewes was about half that of control ewes and there were corresponding increases in K: the differences were significant. Although Na concentrations for experimental ewes were generally lower than those for control ewes in the tissues analysed (liver, kidney, heart, brain and bone), the difference was significant only for the heart (P < 0.05). Haemoglobin and packed cell volume were significantly elevated in low-Na ewes (P < 0.01), indicating decreased body fluid volume. Enlargement of the adrenal glands in low-Na ewes (P < 0.01) and specifically in the zona glomerulosa (P < 0.001), showed the marked hormonal response to Na status of experimental ewes given a very-low-Na diet over two reproductive cycles.