bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of early postnatal undernutrition on the growth and development of the rat brain
Authors: Morgan B. L. G. , Naismith D. J. 
Published: May 2005

1. Rat pups were undernourished during the period of the brain growth-spurt by feeding their mothers a low-protein diet from the third day post partum.2. The pups were killed on days 5,6,9,12,16,20 and 24 post partum, and their brains were analysed for protein, DNA, glycosides and glycoproteins. The activities of four enzymes involved in neurotransmission, and in the synthesis of glycolipids and myelin were also measured. Results of the analyses were compared with those obtained for pups that were suckled by well-nourished dams.3. The brains of the undernourished pups contained substantially less protein and DNA; gangliosides and glycoproteins were also reduced.4. All four enzymes showed lower peak activities in the nutritionally deprived animals, and the attainment of peak activity was retarded by several days.5. These results suggest that undernutrition imposed during the brain growth-spurt leads to a deficit in the glial cell population and thus in the capacity to form myelin, and reduced deveiopment of cellular processes.
The effect of protein-deficient isoenergetic diets on the growth of rat jejunal mucosa
Authors: Syme Gabrielle 
Published: May 2005

1. Newly weaned 21-d-old male rats were given isoenergetic diets containing 200, 100 and 50 g protein/kg for 7, 14, 28 or 70 d. The mid-jejunum was removed from the rats and a micrometric analysis of the mucosa was made. The following measurements were made: number of villi/mm2, vilius dimensions, villus surface area, crypt depth, crypt: villus, the number of cells/crypt in metaphase arrest per h.2. Comparisons were made between animals of the same age but on different diets, and animals on the same diet but of different ages. The latter comparison gave information on the effect of protein deficiency on the pattern of maturation of each feature of The villus or crypt studied.3. The effect of protein deficiency was not consistent at each stage of maturation. For instance villus height was decreased when compared with the controls following 28 d on a protein-deficient diet but not after 7 or 70 d.4. The only measurement to be unaffected by protein deficiency was the number of villi per unit area.5. In general the 50 g protein/kg diet had a more pronounced effect than the 100 g protein/kg diet. Protein deficiency delayed maturation by either slowing or inhibiting changes seen in normal maturation.6. In rats given 50 g protein/kg diet, although the villus surface area did not increase as the rats matured there were increases in epithelial cell production rate and number of crypts per villus.
The effect of protein supplementation on digestion and glucose metabolism in young cattle fed on silage
Authors: Gill Margaret , Beever D. E. 
Published: May 2005

1. Ryegrass (Lolium multiflorumcv. RvP) silage was given to twelve Friesian steer calves (initial live weight (LW) 106 kg) at 2·3 kg dry matter (DM)/calf per d, alone, or with a supplement of fish meal at 50(FM1) or 100(FM2) g/kg silage DM per d.2. The rate of flow of nutrients into the duodenum was measured using a dual-marker technique. Glucose irreversible-loss rates and the contribution of propionate to gluconeogenesis were measured using continuous infusions of [U-14C]glucose and [2-14C]propionate.3. Amino acid flow into the duodenum was significantly (P< 0·01) increased from 238 g/d on the control treatment to 319 g/d on FM2, but there was no response to FM1 (P> 0·05).4. Glucose irreversible loss rate remained constant with an average value of 1·86 mg/min per kg LW.5. Neither the percentage of glucose synthesized from propionate (average 30) nor the percentage of propionate converted to glucose (average 45) was significantly altered by treatment (P> 0·05).
Foetal and maternal rates of urea production and disposal in well-nourished and undernourished sheep
Authors: Hodgson J. C. , Mellor D. J. , Field A. C. 
Published: May 2005

1. Five monotocous and twoditocous Scottish Blackface ewes with indwelling catheters in an umbilical artery and vein of one foetus only and in both maternal jugular veins were used.2. Experiments were conducted over a period of 2 d when [I4C]urea was infused intravenously over 9 h into either the mother or foetus, separate days being used for each infusion. Two series of experiments were completed, one in well-nourished and the other in undernourished sheep at 125–141) and 138–143 d of gestation respectively.3. Plasma urea specific radioactivities of the mother and infused foetus at plateau were used to determine the urea flux-rates within and between mother and foetus. The mean rate of foetal urea production (Ffo) was 1.45 and 1.63 mg/min per kg foetus in well-nourished and undernourished ewes respectively. The corresponding rates of maternal urea production (Fmo) were 0.49 and 0.37 mg/min per kg live weight respectively and there was a close correlation between the rate of maternal urea disposal (Fom) and the dietary nitrogen intake.4. The values ofFfowere used to calculate the maximum potential for foetal gluconeogenesis from deaminated amino acids. These calculations were compared with published information on the over-all rates of foetal gluconeo genesis in well-nourished ewes.5. The foetal entry rate of urea expressed on a body-weight basis was high, approximately 8.5 times that of the mother, but it was a threefold overestimate ofFfo. The maternal entry rate was 1.3 timesFmoand the significance of this in relation to assessing differences in urea entry rates in pregnant and non-pregnant sheep is discussed.
The effects of cold exposure of pregnant sheep on foetal plasma nutrients, hormones and birth weight
Authors: Thompson G. E. , Bassett J. M. , Samson Debbie E. , Slee J. 
Published: May 2005

1. Five pregnant sheep, with indwelling catheters positioned for withdrawal of maternal right-atrial and foetal arterial blood, were exposed for 2 h to neutral and to cold (– 1° and wool-clipped) environmental temperatures. Acute maternal cold exposure increased the concentrations of glucose, glycerol and non-esterified fatty acids in maternal plasma and increased the concentration of glucose in foetal plasma, but not glycerol or non-esterified fatty acids. The concentration of corticosteroids in maternal piasma increased. The concent ration of corticosteroids in foetal plasma did not change but the concentration of insulin increased.2. Thirteen pregnant sheep were housed at thermoneutrality and thirteen similar, sheep fed the same amount of food, were clipped and exposed to cold during the last 5– 6 weeks of pregnancy. Chronic maternal cold exposure increased the birth weight of both single and twin lambs.3. It is concluded that exposure of pregnant sheep to cold can alter the partition of some nutrients between mother and foetus in favour of the foetus, and it is suggested how this may be brought about.
In vitro energy costs of NA+, K+ATPase activity and protein synthesis in muscle from calves differing in age and breed
Authors: Gregg V. A. , Milligan L. P. 
Published: May 2005

1. An in vitro preparation was used to measure rates of oxygen consumption, Na+, K+-ATPase-dependent respiration, [14C]phenylalanine incorporation and tyrosine release of skeletal (stenomandibularis) muscle from 10-21 -d-old (three) and 7-month dairy (three) calves and control (CDM; four) and extreme double-muscled (EDM; two) calves.2. Rate of oxygen consumption was greatest (P< 0.001) for muscle from 10.21-d-old dairy calves and lowest (P< 0.05) for CDM calves.3. Ouabain (10−6M) caused a 40% inhibition of muscle respiration.4. Na+, K+-ATPase-dependent respiration was similar for muscle from all calf groups except 10-21-d-old dairy calves which had a value 26% greater (P< 0.001) than that of older dairy calves.5. Na+, K+-ATPase-independent respiration was 16% greater (P< 0.001) for muscle from 10.21-d-old than that of older dairy calves while muscle from EDM calves had a value 11 % greater than that of CDM caives.6. The rate of [14C]phenylalanine incorporation was greater (P< 0.05) for muscle from 10-21-d-old dairy than from older dairy calves, similar between older dairy and CDM calves, and decreased (P< 0.05) for EDM calves.7. Rate of tyrosine release was greatest (P< 0.05) for muscle from CDM and EDM calves: both dairy groups had similarly low rates of muscle tyrosine release.8. The energy estimated to be required for peptide bond synthesis accounted for 2.0–3.3% of the O2consumption of the muscle preparations.
The influence of diet on the exocrine pancreatic secretion of growing pigs
Authors: Partridge I. G. , Low A. G. , Sambrook I. E. , Corring T. 
Published: May 2005

1. Pancreatic juice was collected from six pigs of 48 kg initial weight fitted with a collection catheter in the pancreatic duct and a return catheter in the duodenum.2. Measurements of flow and composition of the juice were made during 24 h periods after adaptation to isonitrogenous diets based on barley, wheatings and fish meal (diet BWF) or starch, sucrose, casein, maize oil and cellulose (diet SSC), given in a change-over design. Measurements were also made during the periods of adaptation to a change from one diet to the other.3. Mean flow-rates for pigs adapted to diets showed a highly significant four-fold difference between diets; values were 4962 ml/d for diet BWF and 1273 ml/d for diet SSC. The hourly volumes of juice were very variable and showed no clear response to feeding and no consistent diurnal pattern for either diet.4. There were no significant differences between diets in the specific activities of the proteases. Average values were (units/nig protein) trypsin. (EC3.4.21.4) 29·6, chymotrypsin (EC3.4.21.1) 7·7, carboxypeptidase A (EC3.4.17.1) 0·65, carboxypeptidase B (EC3.4.17.2) 1.6. The total output of each tended to be higher with diet BWF than with diet SSC. The specific activities and tolal outputs of α-amylase (EC3.2.1.1) and lipase (EC3.1.1.3) were significantly higher for diet BWF than for diet SSC; specific activities for the two diets respectively were: (units/mg protein) α-amylase 95·6 and 42·3, lipase 59·0 and 14·5.5. The higher daily volume of juice with diet BWF was associated with significantly (but only slightly) higher levels of both sodium and potassium, compared with diet SSC.6. The results are discussed in relation to previous studies on digestion at this Institute, in which pigs with intestinal cannulas were given the same diets.
Interrelationships between biotin, choline and other B-vitamins and the occurrence of fatty liver and kidney syndrome and sudden death syndrome in broiler chickens
Authors: Whitehead C. C. , Randall C. J. 
Published: May 2005

1. Addition of supplemental choline to a biotin-deficient diet decreased the biotin status of chicks and increased mortality from fatty liver and kidney syndrome (FLKS).2. Mortality was also increased by dietary supplementation with a mixture of other B-vitamins, excluding biotin, and was highest when the choline and B-vitamin supplements were combined.3. The occurrence of sudden death syndrome (SDS) was unaffected by dietary biotin concentration.4. A previously unreported condition was observed in which birds died showing post-mortem signs characteristic of both FLKS and SDS and whose occurrence was related to the biotin status of the chicks.
The metabolism of maltitol in the rat
Authors: Lian-Loh Rebecca , Birch Gordon G. , Coates Marie E. 
Published: May 2005

1. Conventional (CV) rats were given a single oral dose of 1 or 2 g maltitol. Urine and faeces were collected during the following 24 h and their contents of maltitol and sorbitol were measured.2. Very little of either substance appeared in the faeces but appreciable amounts of sorbitol found in the urine indicated that the maltitol had been hydrolysed.3. Excretion of maltitol and sorbitol was compared in germ-free and CV rats given an oral dose of 2 g maltitol. Significantly less of both substances was recovered in the faeces of CV rats, but urinary excretion was similar in both environments.4. Maltitol injected intravenously gave rise to only traces of sorbitol in the excreta. A dose of 250 mg was cleared almost completely from the circulation within 1 h.5. It is concluded that maltitol is hydrolysed by animal tissues, either in the gut lumen before absorption or in the gut wall during absorption. Maltitol and sorbitol are also degraded by gut bacteria, mostly in sites distal to the main absorptive area. The contribution to the host's nutrition would depend on the extent to which the end-products of fermentation are absorbed from the colon.
The origin of urinary aromatic compounds excreted by ruminants
Authors: Martin A. K. 
Published: May 2005

1. Dietary phenolic cinnamic acids are hydrogenated in the side-chain, demethylated and dehydroxylated in the rumen and are responsible for the large urinary output of benzoic acid by ruminants.2. Decarboxylation of phenolic acids to simple phenols is another reaction of the intestinal microflora and experiments were made to determine the extent of this reaction in the rumen of sheep.3. In five experiments phenolic compounds, quinic acid or casein were infused into therumen or abomasum of sheep and increments in urinary outputs of phenolic acids and phenols determined by thin-layer and gas-liquid chromatography.4. Production of phenols was almost exclusively confined to reactions in the rumen.5. Rumen administration of phenolic benzoic or phenylacetic acids which contained a 4-hydroxy substituent yielded large increments in urinary phenol outputs. Other phenolic benzoic and phenylacetic acids were not decarboxytated. Rumen decarboxylation of 4-hydroxy-3-phenylpropionic acid did not occur and decarboxylation of 4-hydroxycinnamic acids was slight.6. Nearly half the tyrosine content of rumen-administered casein was excreted asp-cresol, a decarboxylation product of 4-hydroxyphenylaceticacid,p-Cresol was the principal phenol found in sheepurine.7. Catechol and phenol were consistently found in sheep urine samples andp-ethylphenol, resorcinol, quinol, 4-methylcatechol, orcinoland pyrogallol were also found when suitable precursors were infused to the rumen.8. It is concluded thatp-cresol is a rumen metabolite of tyrosine. The other phenols found are microbial metabolites of phenolic precursorswhich are either widely distributed in plants such as 4-hydroxybenzoic, protocatechuic andvanillic acids or of more limited distribution such as the orcinol glycosides of some Ericaceous plants.
Effect of diet and infusion of volatile fatty acids into the rumen on the concentration of plasma free amino acids in sheep
Authors: Mercer J. R. , Miller E. L. 
Published: May 2005

1. The effect of supplementing barley diets with urea (U), extracted decorticated groundnut meal (GNM) or Peruvian fish meal (PFM) on plasma free amino acid concentrations in sheep have been examined and the first limiting amino acid has been indicated by measuring the changes in the concentration of the plasma essential amino acids (PEAA) during a rumen infusion of a volatile fatty acid (VFA) mixture.2. Three wethers fitted with rumen and re-entrant duodenal cannulas were given isonitrogenous, isoenergetic diets containing (g/kg dry matter (DM)) U 20, GNM 106 or PFM 78, the crude protein (nitrogen × 6.25) contents being 139, 145 and 148 respectively. The sheep were fed hourly, the mean daily dm intake being 0.634 kg.3. Plasma concentrations of valine, threonine, lysine, isoleucine and leucine were linearly related to their concentrations in duodenal digesta.4. A VFA mixture was infused into the rumen for 6 h to supply (mmol/min) acetate 1.47, propionate 0.22 andn-butyrate 0.27. Blood samples were taken 6 h before, during and 12 h after the end of the infusion.5. The concentration of all PEAA decreased relative to the pre-infusion and post-infusion controls but there were no significant differences between diets.6. The mean decreases in concentration averaged over all three diets showed that the decrease in concentration of methionine (41.5%) was far greater than for any other essential amino acid suggesting that under these conditions methionine was the first limiting amino acid.
The effect of protein- and non-protein-nitrogen supplements to maize silage on total amino acid supply in young cattle
Authors: Cottrill B. R. , Beever D. E. , Austin A. R. , Osbourn D. F. 
Published: May 2005

1. A total of six diets based on maize silage were formulated to examine the effect of protein- and non-protein-nitrogen, and energy supplementation on the flow of amino acids to the small intestine and the synthesis of microbial amino acids in the rumen of growing cattle. All diets contained 24 g totai nitrogen (N)/kg dry matter (DM), of which 550 g N/kg total N was supplied by either urea or fish meal. Four diets contained low levels of barley (estimated total dietary metabolizable energy content of 10·4 M J/kgDM) and urea-N and fish meal-N were supplied in the ratios 3:1, 1·4:1, 0·6:1 and 0·3:1. The other two diets contained between 300 and 400 g barley/kg total diet (11·3 MJ metabolizable energy/kg DM) and the urea-N to fish meal-N ratios were 3:1 and 0·3:1.2. On the four low-energy diets, fish meal inclusion tended to reduce the extent of organic matter (OM) digestion in the rumen but significantly increased duodenal amino acid supply (P< 0·05) in a quadratic manner. Microbial-N synthesis was increased by the two intermediate levels of fish meal supplementation but declined at the highest level of inclusion. With increasing levels of fish meal inclusion, a greater proportion of the dietary protein was found to escape rumen degradation and the apparent degradabilities of fish meal and maize-silage protein of all four diets were estimated to be 0·22 and 0·73 respectively.3. The substitution of barley for part of the maize silage enhanced duodenal supply of amino acids, irrespective of the form of the N supplement, and stimulated microbial amino acid synthesis. For all diets efficiency of microbial-N synthesis was found to vary between 22·5 and 46 g N/kg rumen-digested OM. Contrary to what was found for low-energy diets, the inclusion of fish meal tended to reduce the flow of dietary protein to the small intestine, but these differences were not statistically significant.4. The results appertaining to microbial synthesis, dietary protein degradabilities and duodenal amino acid flow for all diets are discussed in relation to the Agricultural Research Council (1980) proposals for the protein requirements of ruminants, and the production responses observed when similar diets were fed to growing cattle.
Formaldehyde-treated proteins for dairy cows – effects on blood hormone concentrations
Authors: Oldham J. D. , Hart I. C. , Bines J. A. 
Published: May 2005

1. Seven Friesian heifers in mid-lactation were used in an experiment to measure the effects of including casein, formaldehyde-treated casein or formaldehyde-treated soya-bean meal in the diet on performance and on the concentrations of certain metabolites and hormones in the blood.2. Milk yield and the concentration of fat, protein and lactose in milk were not affected by the treatments.3. The concentration of growth hormone (GH) in jugular venous blood was higher with both formaldehyde-treated proteins than it was with untreated casein (P< 0·05). Diet had no effect on insulin, prolactin or thyroxine concentrations in blood.4. Urea concentration tended to be higher and non-esterified fatty acids lower in blood from heifers offered the diet containing untreated casein, but these differences were not statistically significant. Blood glucose concentration was not affected by dietary treatment.5. It was concluded that blood GH concentration can be increased by offering protein supplements which will increase total amino acid supply to the intestines in lactating cattle. This appears to be a direct effect on GH status independent of effects on milk yield.
What sort of teenager has high intakes of energy and nutrients?
Authors: Woodward David R. 
Published: May 2005

1. An alternative statistical technique, based on analysis of the 75th percentile, was used to examine teenagers' diets. The technique was developed to identify personal characteristics that affected the prevalence of high 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, the prevalence of high intakes of energy and several nutrients was not affected by any of the fifteen characteristics studied. (In this context, ‘high’ was defined as above the 75th percentile for girls.) Fatter, heavier girls were less likely to have high intakes of carbohydrate, iron and niacin-equivalent, and also of meat and ‘empty-energy’ foods. Girls from small families were less likely to have high calcium intakes, and girls from goverment schools less likely to have high thiamin intakes.4. Among boys, age generally had the greatest influence on the prevalence of high intakes (‘high’ being defined as above the 75th percentile for boys). Older boys were more likely to have high intakes of energy and most nutrients, as well as meat, cereals and fruit and vegetables. These age-related changes were, however, rather asynchronous. High fat intakes were more common among boys wbo had drunk more than five glasses of alcoholic beverages in the preceding week. High Ca intakes were more frequent among those who exercised vigorously, and high vitamin A intakes less common among the sons of well-educated mothers.
The impact of adjustment of a weight-height index (W/H2) for frame size on the prediction of body fatness
Authors: Rookus Maartje A. , Burema Jan , Deurenberg Paul , Van Der Wiel-Wetzels Wilhelmina A. M. 
Published: May 2005

1. The impact of frame-size categories in weight-height tables was studied by comparing the efficiency of the body-mass index (weight/height2 (W/H2)) and weight adjusted for body-height and a body-diameter, W/(H2Dp), in predicting body fatness.2. Body-weight, body-height, six body-diameters and four skinfold thicknesses were measured in ninety-five men and seventy women, aged between 23 and 35 years. Percentage of body fat was calculated from skinfold thicknesses using regression equations according to Durnin & Womersley (1974).3. The inclusion of a body-diameter increased the explained variation of body fatness from 57% to 62% (knee) and 63% (shoulder) in men and from 63% to 69% (knee) in women.4. It can be concluded that in the present population the efficiency of the prediction of percentage of body fat was not improved markedly by the inclusion of a body-diameter in the body-mass index, thus giving no support for the inclusion of frame-size categories in weight-height tables.