bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum and urinary hormones during pregnancy and the peri‐ and postpartum period in an Asian elephant (Elephas, maximus)
Authors: Brown Janine L. , Lehnhardt John
Published: June 2005

Blood and urine samples were collected weekly from an Asian elephant (Elephas maximus) for 10 months before conception, throughout pregnancy, and for 10 months after parturition. Additional daily samples were collected for 41 days before through 10 days after parturition to define endocrine events during the peripartum period. During gestation, serum progesterone concentrations increased gradually and, after ∼13 weeks, were higher (P < 0.05) than those observed during the nonpregnant luteal phase. Concentrations peaked at ∼12 months of gestation, gradually declined during the last month, and then decreased sharply to nondetectable levels 2 days before parturition. A 12 week lactational anestrus was observed before cyclicity resumed. The urinary profile of progestagen excretion paralleled that of circulating progesterone (r = 0.79; P < 0.05); however, radioimmunoassay of HPLC‐separated fractions of urinary eluates indicated that this immunoactivity was not associated with native progesterone. After remaining basal through the first 16 weeks of gestation, serum prolactin concentrations increased to 100‐fold about midterm and remained elevated until after parturition. Neither serum nor urinary cortisol concentrations were altered during pregnancy, but both increased markedly the day after parturition and remained elevated above prepartum levels for several weeks thereafter. These data indicate that analysis of serum prolactin can confirm pregnancy in the Asian elephant after ∼4 months of gestation and that daily monitoring of serum or urinary progestagens is useful for predicting parturition. © 1995 Wiley‐Liss, Inc.

This article is a US Government work and, as such, is in the public domain in the United States of America.
Neutral composition effects on ionospheric storms at middle and low latitudes
Authors: Liou K. , Newell P. T. , Anderson B. J. , Zanetti L. , Meng C.‐I.
Published: June 2005

The two‐dimensional structure of thermospheric neutral composition, specifically, the atomic oxygen to molecular nitrogen column density ratio, [O/N2], is studied during the 17–24 April 2002 geomagnetic storms to understand the cause of ionospheric storms in regions equatorward of the auroral oval on an instantaneous large scale. The [O/N2] ratio is derived from the dayglow emission ratio of O I 1356 Å to N2 Lyman‐Birge‐Hopfield (1600–1800 Å) acquired from the Polar ultraviolet imager (UVI) and the total electron content (TEC), which is used to infer ionospheric storms, is derived from the phase delays of dual‐band global positioning satellite (GPS) accumulated around the globe. It is found that the regions of decreasing [O/N2] generally coincided with the regions of depleted TEC during and after the development of the storms. This is consistent with previous theoretical and experimental analysis in which composition changes play a major role in the negative ionospheric storm effects. At lower latitudes, long‐lived positive storm effects predicted by empirical and general circulation models were not observed. In fact, there was no noticeable change in [O/N2]. The TEC data also showed no noticeable change, except a few “short‐lived,” localized positive TEC perturbations. For this particular event, the equatorward expansion of the decreased [O/N2] at the onset of the first storms was estimated to be more than 600 m/s, much faster than the typical thermospheric wind, and reached ∼30°N in 2 hours much equatorward (>25° MLAT) beyond the auroral electrojets. This result suggests that midlatitude (negative) ionospheric storms are caused by direct equatorward penetration of a reduced thermospheric [O/N2], at least during the first few hours of storms.
Bias in Dobson total ozone measurements at high latitudes due to approximations in calculations of ozone absorption coefficients and air mass
Authors: Bernhard G. , Evans R. D. , Labow G. J. , Oltmans S. J.
Published: June 2005

The Dobson spectrophotometer is the primary standard instrument for ground‐based measurements of total column ozone. The accuracy of its data depends on the knowledge of ozone absorption coefficients used for data reduction. We document an error in the calculations that led to the set of absorption coefficients currently recommended by the World Meteorological Organisation (WMO). This error has little effect because an empirical adjustment was applied to the original calculations before the coefficients were adopted by WMO. We provide evidence that this adjustment was physically sound. The coefficients recommended by WMO are applied in the Dobson network without correction for the temperature dependence of the ozone absorption cross sections. On the basis of data measured by Dobson numbers 80 and 82, which were operated by the National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory at the South Pole, we find that omission of temperature corrections may lead to systematic errors in Dobson ozone data of up to 4%. The standard Dobson ozone retrieval method further assumes that the ozone layer is located at a fixed height. This approximation leads to errors in air mass calculations, which are particularly relevant at high latitudes where ozone measurements are performed at large solar zenith angles (SZA). At the South Pole, systematic errors caused by this approximation may exceed 2% for SZAs larger than 80°. The bias is largest when the vertical ozone distribution is distorted by the “ozone hole” and may lead to underestimation of total ozone by 4% at SZA = 85° (air mass 9). Dobson measurements at the South Pole were compared with ozone data from a collocated SUV‐100 UV spectroradiometer and Version 8 overpass data from NASA's Total Ozone Mapping Spectrometer (TOMS). Uncorrected Dobson ozone values tend to be lower than data from the two other instruments when total ozone is below 170 Dobson units or SZAs are larger than 80°. When Dobson measurements are corrected for the temperature dependence of the ozone absorption cross section and accurate air mass calculations are implemented, data from the three instruments agree with each other to within ±2% on average and show no significant dependence on SZA or total ozone.
Enhancement of the 1988 northern U.S. drought due to wildfires
Authors: Liu Yongqiang
Published: June 2005

Drought provides a favourable environment for the ignition and spread of intense wildfires. This study examines the opposite relationship between the two natural disasters, that is, the role of wildfires in the development of drought. The case of the 1988 northern U.S. wildfires is investigated. Emissions of smoke particles from the wildfires and the resulting optical depth are estimated using wildfire data and empirical algorithms. Radiative forcing of the smoke particles and atmospheric response are simulated using a regional climate model. It is found that absorption of solar radiation by smoke particles weakens the North America trough in the middle latitudes, which is a major generator of precipitation in the Midwest. Rainfall in this region is therefore reduced, providing evidence for the role of wildfires in enhancing drought.
A preliminary study of the effect of pregnancy and of lactation on the voluntary intake of food by cows
Authors: Campling R. C.
Published: June 2005

1. Monozygotic twin cattle were used in a preliminary study of the effect of pregnancy and of lactation on the voluntary intake of food and water, and on eating and ruminating behaviour. Also, results are reported of an experiment with five pairs of monozygotic twin heifers to examine the variation within pairs of twins in voluntary intake of food and water and eating and ruminating behaviour.

2. Voluntary food and water intakes were measured during the last few weeks of pregnancy and during early lactation. Within each twin pair one twin was pregnant or lactating and the other non-lactating and not pregnant, and the food and water intakes of a pair of twins were measured simultaneously.

3. On average the variation in voluntary intake of hay within pairs of non-pregnant, monozygotic twin heifers was 0.2 kg or 3 % of the mean daily hay intake.

4. The effect of pregnancy was observed in six pairs of twins and in five of the pairs the pregnant animal ate iess hay than its non-pregnant twinmate; in four of these five pairs the effect was small (13 % ). Changes in eating and ruminating behaviour associated with pregnancy were small; the pregnant animals ate concentrates and hay more slowly and ruminated longer than the non-pregnant animals.

5. Lactation was associated with a mean increase of 29 % in hay intake in eight out of the nine pairs studied. In four pairs of twins given a diet of concentrates alone the lactating animal ate on average 8 % more than the non-lactating animal. The lactating cows tended to eat concentrates and hay more quickly than the non-lactating cows; because of differences in the ratio of hay to concentrates it was not possible to interpret the changes in rumination that occurred with lactation.
The effect of lowered environmental temperature on lipid metabolism in rats fed on normal and high-fat, high-cholesterol diets
Authors: Bobek P. , Ginter E.
Published: June 2005

1. Prolonged intermittent exposure to reduced environmental temperature (+2°) produced in rats given a nutritionally well-balanced diet a decrease in the concentration of esterified fatty acids in the blood serum, liver and epididymal fat tissue. In the last there was a significant increase in the unesterified: esterified fatty acid ratio. The hepatic synthesis of fatty acids from [1–14C]acetate remained unchanged. A decrease in the concentration of cholesterol was found in the blood serum, liver and lungs of animals exposed to cold.

2. When a high-fat, high-cholesterol diet was given, exposure to cold increased the mobilization of lipids; this was indicated by the elevation of the unesterified fatty acid levels in the blood serum and in the epididymal fat tissue. In rats given the high-fat diet the lipotropic action of cold on the liver was confirmed. This action was characterized by a decrease of esterified fatty acid levels and by an increase of glycogen concentration in the liver. This effect is probably due to a lowering of hepatic lipogenesis and to increased oxidation of fatty acids in the liver tissue. In rats given the high-fat dict, cold exposure produced an increased cholesterol accumulation in the tissues and more pronounced morphological changes in the myocardium.
The distribution and metabolism of α-tocopherol in the rat
Authors: Mellors A. , Barnes M. McC.
Published: June 2005

1. A comparison of the distribution of radioactivity in rat tissue lipids after oral administra- tion of [5-Me-14C]-α-tocopherol showed that spleen and adrenal lipids have a relatively high uptake of radioactivity. 2. Absorbed α-tocopherol and its metabolites appeared not to re-enter the lumen of the gut in significant amount through the bile or by the secretion from the stomach mucosal cells within the 24 h experimental period. 3. After ingestion of [5-Me-14C]-α-tocopherol by rats, analyses of their liver and spleen lipids showed that most of the radioactivity in the lipids was due to the presence of unchanged α-tocopherol. Radioactive tocopherolquinone was found in both spleen and liver lipids; in the liver lipids there was some evidence that a second oxidation product of α-tocopherol, compound O, had been formed.
Nutritional effects of autoxidized fats in animal diets
Authors: Lea C. H. , Parr L. J. , L'estrange J. L. , Carpenter K. J.
Published: June 2005

1. Turkey poults were fed from day-old to 6 weeks on a practical-type diet containing 10 % white fish meal (supplying 0.7 % lipid) and other constituents, mainly cereals (supplying 3.3 % lipid), together with either 1.5 % of anchovy oil that had been allowed to autoxidize under various conditions or 1.5 % of fresh beef fat.

2. For group I the whole diet with anchovy oil was stored in air at 15° for 3 months before feeding. Its lipid oxidized only slowly, with no appreciable rise in peroxide value and little destruction of its polyunsaturated fatty acids. For groups 2 and 3 the anchovy oil was mixed with the white fish meal, and the mixture was stored for 3 months, by which time most of its polyunsaturated fatty acids had been destroyed by autoxidation and the pv of the extractable lipid, after reaching a peak of 260 μmoles/g, had fallen again to 110. At this point the anchovy oil-fish meal premixture was further mixed with the basal diet and used, either immediately (group 2) or after 3 months' further storage (group 3). 3. The turkeys in all three groups receiving ‘fish oil’ remained healthy and grew well, with only slightly apparent (and not significantly) lower weight gains than those on the control diet. There was no significant treatment effect on liver weight, serum aspartate amino-transferase or serum alanine aminotransferase activity. All the birds stored vitamin A in their livers, though the diets had provided not more than adequate supplies of this vitamin, but the reserves accumulated were significantly lower when the diets contained oxidized fat. On roasting, the turkeys of group 1 had a definite and objectionable fishy flavour, whereas those of groups 2 and 3 were as palatable as the controls on the beef fat diet.
Early changes in enzyme activity during the development of and recovery from vitamin D deficiency in the rat
Authors: Cheesman Elisabeth M. , Copping Alice M. , Prebble Patricia M.
Published: June 2005

1. Rats were given a rachitogenic diet with or without vitamin D for 1, 2, 3 or 4 weeks, and vitamin D was administered to a group of rats which had been deprived of vitamin D for 3 weeks. 2. Changes in enzyme activities of some tissues were followed histochemically. In general, changes in parathyroid preceded those in gut and kidney. Leucine aminopeptidase activity rose in the parathyroid, kidney and jejunum of the vitamin D-deficient rat as did the ribonucleic acid content of the parathyroid and the dehydrogenase activity of the gut. In contrast, the phosphatase activity of the gut and kidney fell in the vitamin D-deficient rat. All these changes were reversed during the 1-week recovery period. 3. A slower response of bones to both vitamin D deprivation and vitamin D dosage after deprivation was indicated by the changes in the percentages of ash in the bones and the changes in number and distribution of osteoclasts.
The use of tritiated water, 4-aminoantipyrene andN-acetyl-4-aminoantipyrene for the measurement of body water in living pigs
Authors: Kay M. , Jones A. S. , Smart R.
Published: June 2005

1. Body water content was estimated in sixteen pigs at each of three weights 27, 55 and 90 kg with tritium, 4-aminoantipyrene (4-AA) andN-acetyl-4-aminoantipyrene (NAAP). The values obtained were compared with chemical analysis of the whole carcass. 2. The tritium method estimated total body water content accurately at 27 kg live weight but overestimated it by approximately 10% at both 55 and 90 kg live weight. 3. Antipyrene was eliminated from the pig at a rate of 55%/h and could not be used for body water estimations. 4. Measurements with NAAP on nine pigs tended slightly to underestimate total body water content. Estimates with 4-AA showed no association with the values obtained by chemical analysis.
Adaptation of the rat to a low-protein diet: the effect of a reduced protein intake on the pattern of incorporation of L-[14C]lysine
Authors: Waterlow J. C , Stephen Joan M. L.
Published: June 2005

1. Rats were chronically depleted of protein by being kept on a 6% casein diet for 5–8 weeks. Control rats were fed on a normal diet. Both groups were injected intraperitoneally with L-[U-14C]lysine. Some rats from each group were then put on a protein-free diet to produce acute depletion. The animals were killed 3 days after the injection. 2. The organs and tissues were analysed for total nitrogen and radioactivity. Free lysine, total amino N and specific activity of free lysine were measured in muscle, liver and serum. The total muscle mass of the animals was determined. Samples of muscle and skin were fractionated and the sp. ac. of the fractions was measured. 3. The main loss of N in acute depletion was found in the viscera and carcass residue; the percentage of total body N contributed by muscle was increased in protein-depleted rats. 4. The depleted rats retained relatively more radioactivity in the internal organs and less in the carcass than normal rats. 5. The ratio of the sp. ac. in protein-bound lysine to the sp. ac. of free lysine showed that protein synthesis was reduced in the muscle of the protein-depleted rats, although there was no decrease in the amount or sp. ac. of free lysine even in severe depletion. 6. Sarcoplasmic and fibrillar proteins of muscle were equally affected by protein depletion, but there was some indication of a preferential decrease in protein synthesis in one of the skin fractions. 7. The results for muscle protein are compared with those given in the literature for liver proteins. It is suggested that the rat adapts to a low-protein intake by an alteration in the pattern of protein synthesis.
Influence of diets containing different natural oils on the incorporation of [1-14C]acetate in the various lipid fractions of rat liver
Authors: Bhattathiry E. P. M.
Published: June 2005

1. A comparative study was undertaken with rats on the effect of various diets (normal stock, fat-free, palm oil and olive oil) on the in vitro incorporation of [14C]acetate by the liver into cholesterol and into the fatty acids of phospholipids and neutral fats. 2. The total lipids extracted from the incubation mixtures were fractionated into acetone-precipitable and digi- tonin-precipitable portions and also into the fatty acids of neutral lipids. 3. The incorporation of [14C]acetate into the acetone-precipitable fraction and into fatty acids of neutral fats was greatest in livers of rats given the fat-free diet, followed by those of the groups given olive oil, the normal stock diet, and palm oil. Livers from the group given the fat-free diet also exhibited the highest percentage of14C activity in the digitonin-precipitable fraction and were closely followed by the group on the normal stock diet. Compared with those of the other two groups, the livers of the groups given olive oil and palm oil showed much less activity in the digitonin- precipitable fraction. 4. The greater the amount of a specific type of fatty acid in the diet, the less was the14C activity incorporated into that type of fattyacid in the ncutral fats of liver slices, hut this was not so with the fatty acids obtained froin the acetone-precipitahlc fraction of the lipids.
Severe undernutrition in growing and adult animals
Authors: Lister D. , Cowen T. , McCance R. A.
Published: June 2005

1. Rhode Island Red and Light Sussex poultry attained their full size in about 6 months.

2. When they were held back by undernutrition so that they weighed only about 170g at 6 months of age and were then given unlimited food, they grew—like the normal birds—for about 6 months, i.e. till they were 1 year old, but still they did not attain the same stature as normal birds. 3. The pullets more nearly attained the size of their controls than did the cockerels. 4. On rehabilitation after the period of undernutrition poultry frequently suffered leg weakness which in its extreme form could be diagnosed as perosis. 5. Rehabilitated pullets began to lay large eggs after a comparatively short period of growth and when they were still a small size.
Some effects of overfeeding for four days in man
Authors: Strong J. A. , Shirling D. , Passmore R.
Published: June 2005

1. Food which provided from 2960 to 7880 kcal in excess of requirements was eaten by sixteen subjects, ten hospital patients and six students, in each instance for a period of 4 days.

2. The proportion of the nutrients lost in the faeces was not increased during overfeeding.

3. The metabolic rates were in no instance increased by an amount equivalent to more than 15% of the excess calories. The increase could be attributed to the specific dynamic action of the extra dietary protein.

4. The gains in weight ranged from 370 to 5460 g/4 days and the calorie equivalent of the weight gained varied from 1·1 to 10·0 kcal/g. These variations can be attributed to variations in the amount of water retained.

5. Analysis of their respiratory exchanges suggests that most subjects stored from 400 to 1500 g of carbohydrate in the tissues, possibly in the form of muscle glycogen.
Phospholipids of the liver in children suffering from protein–calorie undernutrition
Authors: Chatterjee K. K. , Mukherjee K. L.
Published: June 2005

1. Thirty-nine children suffering from protein–calorie undernutrition were classified into nineteen with kwashiorkor, twelve with marasmus and eight with nutritional oedema according to history, physical findings and laboratory investigations. Liver biopsy samples from these patients were extracted with lipid solvents and the phospholipids were fractionated into phosphatidylcholine, ethanolamine and serine, and sphingomyelin.

2. The total liver phospholipids were found to be reduced in kwashiorkor and the reduction was mainly in the phosphatidyl ethanolamine fraction. The decrease in phosphatidyl ethanolamine was probably due to an observed reduction in free serine content. The ethanolamine phosphatase activity of the liver was found to be high in kwashiorkor.
The measurement of hair growth as an index of protein synthesis in malnutrition
Authors: Sims R. T.
Published: June 2005

1. The purpose of this paper is to propose the measurement of scalp hair diameter as a useful index of protein synthesis in the management of cases of malnutrition.

2. Observations on scalp hair from ten control infants showed that each hair tapered very gradually towards its free end.

3. Observations on scalp hair from twenty-six infants with kwashiorkor showed that each hair narrowed towards the follicle; the effect was statistically significant.

4. After I month's treatment for kwashiorkor, scalp hair thickened towards the follicle and the effect was statistically significant.

5. Serial measurements of the greatest diameter at 0·5 mm intervals along the hair shaft had a main trend which was related to nutritional history.

6. The period of time over which narrowing of the hair shaft took place was calculated from the rate of hair growth and the serial diameter measurements: this time was always longer than the history of kwashiorkor.
Observations on the nature and origin of lipids in the small intestine of the sheep
Authors: Lennox Aileen M. , Lough A. K. , Garton G. A.
Published: June 2005

1. Total lipids were extracted from digesta obtained from the rumen, abomasum and upper small intestine (jejunum) of each of four slaughtered sheep. The lipids were fractionated into unesterified fatty acids, neutral lipids and phospholipids and the proportional contribution of each fraction to the total fatty acids was determined.

2. The contribution made by phospholipids to the total fatty acids in the digesta showed a marked increase in the samples from the small intestine compared with those from the rumen and abomasum. This increase was apparently due to the presence of biliary phospholipids.

3. Total lipids and conjugated bile acids were extracted from sheep bile, the lipids were fractionated and their fatty-acid composition was determined. Phospholipids predominated and these consisted mainly of phosphatidylcholine, together with some lysophosphatidylcholine.

4. Both phospholipids contained significant amounts of unsaturated C18components which could account, at least in part, for the previously reported increament to the proportion of these acids in the digesta when it enters the upper jejunum.

5. The overall fatty acid compositions of the two biliary phospholipids were very similar and, in common with other naturally occurring phosphatidylcholines, the fatty acids present in position 2 of the phosphatidylcholine of bile were found to consist almost entirely of unsaturated components.

6. Total lipids and conjugated bile acids were extracted from samples of digesta obtained from three sheep with cannulas in different positions in the jejunum. Analysis of the lipids indicated that biliary phospholipids, in particular phosphatidylcholine, underwent progressive hydrolysis in the intestinal lumen.

7. The distribution of conjugated bile acids, unesterified fatty acids and phospholipids between the solid (particulate) and liquid (micellar) phases of the intestinal digesta was determined. These chyme constituents were, for the most part, associated with the particulate matter and thus, at any given time, it appears that only a small fraction of the total fatty acids is available for absorption in micellar form. It is suggested that the micellar solubilization of fatty acids may be facilitated by the presence of lysophosphatidylcholine.
The absorption of long-chain fatty acids from the small intestine of the sheep
Authors: Lennox Aileen M. , Garton G. A.
Published: June 2005

1. Three sheep, each of which was fitted with a rumen cannula and with two pairs of reentrant cannulas in different parts of the small intestine, were used in this study. They were fed on dried grass cubes or hay plus linseed meal and oats: an aqueous solution of polyethylene glycol (PEG) was infused continuously into the rumen.

2. Total lipids were extracted from samples of the chyme entering and leaving the different lengths of the small intestine embraced by the respective cannulas. The lipids were fractionated into unesterified fatty acids, neutral lipids and phospholipids and the contribution of each fraction to the total fatty acids was determined. The samples were also analysed for their PEG content, thus affording an index of the extent to which water had been absorbed from each particular length of intestine.

3. From the above findings and a knowledge of the flow-rate of the digesta, the uptake of unesterified fatty acids and the degree of dissimilation or uptake, or of both, of esterified fatty acids was calculated.

4. The results indicated that, by the time the digesta reached the ileum (i.e. the distal half of the small intestine), the uptake of fatty acids was almost complete, as was also the hydrolytic release of esterified fatty acids.

5. Though there were no gross differences in the overall composition of the unesterified and esterified fatty acids in different parts of the small intestine, it appeared that C18mono-unsaturated acid, the principal unsaturated unesterified acid, was absorbed somewhat more efficiently than were the major saturated acids (palmitic acid and stearic acid).
A note on the estimation of nitrogen retention in chicks by body analysis and balance methods
Authors: Davidson J. , Williams R. B.
Published: June 2005

1. In a balance study with young chicks estimates of nitrogen retention were made by a balance method and by a body analysis method.

2. N retention appeared to be about 15% greater by the balance method when no allowance was made for N in alimentary tract contents. Allowance for tract contents reduced the difference to about 13%.

3. Only about one-third of the discrepancy could be accounted for interms of the possible sources of N loss investigated.

4. About a quarter of the difference was due to loss of N on drying the droppings before analysis and another tenth to loss of N on freeze-drying minced chick tissues.

5. No appreciable loss of ammonia could be detected from chickens and excreta under conditions prevailing in the balance trial. The efficiency of digestion of feathers, uric acid and droppings from birds appeared to be complete by the Kjeldahl method employed.

6. A difference of about 8% could therefore not be explained.
The development of primary teeth in children from a group of Gambian villages, and critical examination of its use for estimating age
Authors: McGregor I. A. , Thomson A. M. , Billewicz W. Z.
Published: June 2005

1. Numbers of erupted primary teeth were counted in young children in four rural villages in The Gambia. The ages of all children were precisely known, and their heights and weights were measured.

2. The majority of children were recorded as having an even number of teeth. The number of primary teeth present in children of given age varied widely. Up to 18 months of age, the Gambian children lagged behind American and European children in number of erupted teeth.

3. From the distributions, it appears that a child having no teeth is unlikely to be over 12 months of age, and one with all primary teeth is unlikely to be under 20 months. Between these dental limits, estimates of age from the number of primary teeth present are likely to be accurate to ± 3 or 4 months.

4. Children who were tall or heavy for age tended to have more teeth than those who were short or light. Thus, children with delayed dentition would be systematically assessed as younger than true chronological age.

5. There was, however, no evidence that slow growth was associated with prolongation of the total period of dental eruption, nor that seasonal variations in rate of growth were associated with similar variations in rate of tooth eruption.
Adaptation of urinary nitrogen excretion in infants to changes in protein intake
Authors: Chan H.
Published: June 2005

1. Thirty-six nitrogen-balance measurements were made on children recovering from malnutrition. Two types of diet were used: a high-protein diet providing from 1·25 to 6·0 g protein/kg per day which supported normal growth, and a low-protein diet providing 0·75 g protein/kg per day on which the children were approximately in N balance. Both diets provided 120 kcal/kg per day.

2. The size of the labile protein pool was estimated from the N lost on changing from a high- to a low-protein diet. After the change of diet a new equilibrium was reached in about 3 days.

3. Labile protein, as defined above, represented about 1·2% of the total body protein on changing from 6·0 to 0·75 g protein/kg per day, and about 0·2% of total body protein on changing from 1·5 to 0·75 g protein/kg per day. The magnitude of the labile protein pool did not appear to be related to the nutritional state of the child.

4. It is concluded that the labile protein pool is not a reservoir which can be filled, but that losses of N which occur on reducing the protein intake of an infant reflect a lag in metabolic adjustment.
Polyethylene glycol as marker in piglet diets with a high dry-matter content
Authors: Manners M. J. , Kidder D. E.
Published: June 2005

1. Polyethylene glycol (PEG) of high molecular weight, used as a dietary marker, did not distribute uniformly in the water present in a high-casein diet as did glucose, a low-molecular-weight substance.

2. This distribution effect also occurred with the contents of the stomach and, to a smaller extent, with the contents of the first quarter of the small intestine of piglets given such a diet.
Manganese in the nutrition and metabolism of the pullet
Authors: Mathers J. W. , Hill R.
Published: June 2005

1. Groups of pullets were given a diet of high (106–107 μg/g) or low (6–7 μg/g) manganese content and killed either before sexual maturity, at the point-of-lay or after a 6- to 7-month laying period. The birds were dissected into six tissue fractions: skeleton, liver, kidney, ovary and oviduct, skin and feathers, and muscle with remaining tissue. Total Mn and concentration of Mn as μg/g dry fat-free tissue were determined for each fraction.

2. There were no differences in live weight attributable to level of dietary Mn, and no differences in egg production.

3. Mean total body Mn varied among groups over a fairly narrow range (528–738 μg), with the exception of birds given the high-Mn diet throughout the experiment, in which the mean was 2319 μg. This represented an increase in Mn content during egg laying of 244%. There was no significant difference in the Mn content of birds given the low-Mn diet whether they were killed at the point-of-lay or after the laying period.

4. The effects of treatment on the weight of Mn in each of the tissue fractions are described. The very large increase in total Mn that occurred during egg production in birds given the high-Mn diet was accounted for largely by the increase in skin and feathers (1072 μg Mn).

5. In general terms, the Mn content of liver, kidney and ovary and oviduct together constituted only just over 10% of total body Mn, the remainder being distributed about equally among skeleton, skin and feathers, and muscle with remaining tissue.

6. There was a close parallel between the concentration of Mn of a tissue and the total weight of Mn it contained except in certain instances when stage of maturity or egg production influenced weight of the tissue.

7. The effects of treatments on the Mn contents of these birds are discussed in relation to the retention of dietary Mn, and the withdrawal from and accumulation of Mn in individual tissues and the whole body.
Comparison of the weight gain and the composition of blood and saliva in sheep grazing timothy and ryegrass swards
Authors: Sinclair K. B. , Jones D. I. H.
Published: June 2005

1. After a preliminary period of 2 weeks indoor feeding on hay, two groups of wethers grazed either a timothy pasture or a ryegrass-dominant pasture for 12 weeks. The timothy was particularly low in sodium and chlorine.

2. Within a week of turning out, saliva sodium fell and potassium increased in the timothy group, and by the end of the experiment, the sodium: potassium ratio was 1.9:1. The changes in saliva were not reflected in blood composition. The rate of live-weight gain was similar in both groups of sheep.

3. The results confirm those of a previous indoor experiment and show that timothy supplies insufficient sodium to maintain the normal saliva composition of sheep.
Long-term vitamin status and dietary intake of healthy elderly subjects
Authors: Rutishauser Ingrid H. E. , Bates C. J. , Paul Alison A. , Black Alison E. , Mandal A. R. , Patnaikt B. K.
Published: June 2005

1. Long-term clinical and biochemical riboflavin status and dietary intake of riboflavin were monitored for 18 months in a group of twenty-three relatively-healthy elderly subjects living at home in the north of England.

2. Both dietary intake and biochemical status, as measured by the activation coefficient (stimulated: basal activity) of NAD(P)H2: glutathione oxidoreductase (EC 1.6.4.2), remained fairly constant for each individual and for most subjects the usual intake and biochemical status were characterized quite accurately by a single week's intake dietary record and a single measurement of the activation coefficient.

The expected relationship between biochemical status and dietary intake was present, but not strongly evident. There was a significant within-subject correlation between α values and the immediately preceding dietary intake; however the between-subject correlation between α values and dietary intake approached zero if the two subjects receiving long-term riboflavin supplements were omitted. Over the limited range of intakes observed in unsupplemented subjects, non-dietary factors evidently obscure the relationship.

4. Although eight subjects had average values above 1.2 for the activation coefficient, no excessively high values were observed, and no subject showed any clear-cut clinical deficiency symptoms.
The differential effect of magnesium deficiency on isoenzymes of alkaline phosphatase (EC3.1.3.1) in rat tissues
Authors: Nehlawi M. F. , Heaton F. W.
Published: June 2005

1. Alkaline phosphatase (EC3.1.3.1) from many rat tissues was separated into two or three bands by electrophoresis on polyacrylamide gel. Ten of the bands had different electrophoretic mobilities, but some were present in more than one tissue.

2. Bands from the corresponding tissues of magnesium-deficient and control rats were qualitatively similar, but there were quantitative differences in the distribution of enzyme activity between them.

3. Mg deficiency had differential effects on the absolute activity of individual bands, but two main types of response were observed. There was an increase in the activity of the first bands from liver and kidney, the second band from femur and both bands from spleen, whereas the first band from femur, the first and second bands from intestinal mucosa and the second bands of serum, liver and kidney all decreased in activity during the deficiency.

4. The change in total alkaline phosphatase activity of a tissue during Mg deficiency depended on the ratio between the enzyme components within it.
A comparative study of the absorption of calcium and the availability of phytate-phosphorus in the golden hamster (Mesocricetus auratus) and the laboratory rat
Authors: Taylor T. G. , Coleman J. W.
Published: June 2005

1. Balance studies were carried out with rats and golden hamsters (Mesocricetus auratus) given diets high and low in calcium (10.8 and 5.1–5.2 g Ca/kg respectively) and high and low in phytate (3.4 and 1.6 g phytate-phosphorus/kg respectively) in a 2 × 2 factorial experiment.

2. Values for Ca absorption and phytate availability (relative to the amount ingested) and for urinary excretion of Ca and P were significantly higher in the hamster than in the rat for all four diets.

3. Phytate availability was significantly greater on the low-Ca than on the high-Ca diets with both species.

4. Ca absorption was greater on the low-phytate than on the high-phytate diets but the differences were significant only for the hamster.

5. Absorption of both Ca and P was poorly controlled in the hamster compared to the rat.
Kinetics of native and modified Bowman–Birk soya-bean trypsin inhibitor on growth and enzymes activities of the chick pancreas
Authors: Madar Z.
Published: June 2005

1. The Bowman-Birk soya-bean trypsin inhibitor (BBTI) begins to cause pancreatic enlargement and increased enzymic activity in the pancreas of chicks after a minimum of 7 d of feeding.

2. The active inhibitory site of BBTI against trypsin is the factor involved in the pancreatic enlargement and increase of pancreatic nzesyme activity in chicks.
Effects of saponins on bile acids and plasma lipids in the rat
Authors: Oakenfull D. G. , Fenwick Dorothy E. , Hood R. L. , Topping D. L. , Illman R. L. , Storer G. B.
Published: June 2005

1. The effects of feeding isolated saponins on plasma lipid concentrations and on concentrations of biliary and faecal bile acids and neutral sterols were studied in the rat.

2. The animals were given one of four diets, i.e. a standard low-cholesterol synthetic diet, the diet+10 g saponins/kg, the diet+10 g cholesterol/kg, the diet+10 g cholesterol+10 g saponins/kg.

3. Saponins partially reversed the hypercholesterolaemia caused by the high-cholesterol diet and increased both the rate of bile acid secretion and the faecal excretion of bile acids and neutral sterols. The proportionate contribution of the primary bile acids (particularly chenodeoxycholic) to faecal excretion was also increased by saponins.

4. The results are discussed in relation to the hypothesis that saponins act by inducing the adsorption of bile acids by dietary fibre.
Effects of the protracted feeding of copper sulphate-supplemented diets to laying, domestic fowl on egg production and on specific tissues, with special reference to mineral content
Authors: Jackson N. , Stevenson Mary H. , Kirkpatrick G. McC.
Published: June 2005

1. Two experiments are reported. In both experiments a cereal-based diet containing 5 mg copper/kg was fed to two breeds of laying hens for 336 d. In Expt I four other groups were given this diet with the addition of CuSO4.5H2O to give added levels of 200, 400, 600 and 800 mg Cu/kg diet. In Expt 2 the levels of added dietary Cu used were 100, 200, 300 and 400 mg/kg.

2. In Expt I records were kept of food intake, water intake, body-weight and egg production for eight 28 d periods and body-weight and egg number only were recorded for the full twelve periods. In Expt 2 full records, excluding water intake, were taken for all twelve periods.

3. Food and water intake showed a quadratic response to level of added dietary Cu, being enhanced at lower levels and depressed at higher levels of addition.

4. There was a quadratic response of total egg weight, mean egg weight and egg number to added dietary Cu. In Expt I egg number was maximum at 235 mg added Cu/kg diet for Warren Studler SSL (breed I) and at 170 mg added Cu/kg diet for Shaver 288 (breed 2). In Expt 2 no breed effect occurred, the maximum egg number being calculated to occur at 176 mg added Cu/kg diet.

5. Depression of body-weight gain occurred at high lelvels of Cu addition. The depression of liver and oviduct weight found at high levels of addition appeared to be directly related to body-weight. A marked amount of feather loss also occurred at a high inclusion of CuSO4in the diet.

6. The reproductive systems of the hens did not appear to be adversely affected at the levels of additive used. Gross and microscopic examination of specific tissues revealed no pathological effects although gizzard and intestinal weights were increased and caecal weight decreased by high levels of added Cu. Those aspects of the blood chemistry examined did not reveal any consistent effect between the two experiments.

7. The liver Cu analyses indicate that between 600 and 800 mg added Cu/kg diet liver Cu concentration rises sharply. Both liver Fe and Zn concentrations showed a positive linear response to added dietary Cu. In the kidney Cu and Zn concentrations were increased but only to a limited extent, while the concentration of Fe was unaffected.
Studies on digestion and absorption in the intestines of growing pigs
Authors: Sambrook I. E.
Published: June 2005

1. Seventeen pigs fitted with single re-entrant cannulas in either the duodenum (posterior to the point of entry of the bile and pancreatic ducts), the mid-jejunum, or the terminal ileum, and a further twenty-four non-cannulated pigs were used.

2. Three diets were used: these contained barley, fine wheat offal, white fish meal, minerals and vitamins (diet BWF); starch, sucrose, maize oil, cellulose, minerals, vitamins and either groundnut meal (diet SSG) or casein (diet SSC).

3. The quantities of total lipid (TL), acid-detergent fibre (ADF) and volatile fatty acids (VFA) passing through the re-entrant cannulas and excreted in the faeces in 24 h were measured. These were used to determine the net absorption (or synthesis or secretion) in the different regions of the intestine.

4. There was substantial secretion of TL into the proximal small intestine and major absorption from the distal portion for all three diets. In the large intestine there was little or no further net absorption for diets SSG and SSC, but significant synthesis or secretion for diet BWF.

5. Fibre digestion occurred in both the small and large intestines and the apparent absorption of ADF in the different regions studied was influenced by diet.

6. There were detectable amounts of VFA at all sites but only at the ileum and in the faeces could they be accurately measured. Diet did not affect the molar proportions of acetate, propionate and butyrate in ileal digesta, but did have an effect on these VFA in the faeces.
Glucose metabolism in cattle given sugar cane based diets supplemented with varying quantities of rice polishings
Authors: Ferreiro H. M. , Priego A. , Lopez J. , Preston T. R. , Leng R. A.
Published: June 2005

1. Glucose entry rates were measured with [2−3H]glucose in groups of cattle given sugar-cane diets and between o and 1200 g rice polishings.

2. In the first experiment measurements of glucose metabolism were estimated in four animals (one of each being given 0, 400, 600 and 1000 g supplement) over 24 h using a repeated single injection at 6 h intervals and sampling blood for 3 h.

3. The results indicated that in a short time period of each isotope experiment relatively steady-state conditions existed since the plot of log specific radioactivity v. time was linear with a high correlation coefficient.

4. The pattern of glucose entry rates was variable over the 24 h period being highest shortly after feeding and then declining to quite low levels immediately before the next feed, 24 h later. However, the more rice polishings that were made available to the cattle, the higher the glucose entry rate at 4–7 h, and it remained higher for a longer time.

5. In the second experiment with nineteen animals there was a linear relationship between the glucose entry rate (measured 4–7 h after feeding) and the amount of rice polishings consumed by the animal.

6. The results suggest that glucose is being made available in quite large quantities from the supplement. Using the means of these estimates over 24 h to predict glucose entry rate on a daily basis, it is suggested that at least 50% of the starch in the rice polishings was made available to the animal as glucose.

7. The results are discussed in relation to the suggestion that the availability of glucose may be limiting nutrient in cattle given low-protein diets.
The effect of oral contraceptive therapy and of pregnancy on serum folate levels of rural Sri Lankan women
Authors: Hettiarachchy Navam S. , Sri Kantha Sachi S. , Corea S. M. X.
Published: June 2005

1. Serum folate level, packed cell volume and haemoglobin concentration of apparently healthy rural Sri Lankan women, between 20 and 45 years and earning up to Rs. 500 (Sri Lankan Rs. 35 ⋍ £1 Sterling) per month, were estimated during pregnancy and when on oral contraceptive (OC) treatment with Ovulen 50 (ethinyl oestradiol 0·05 mg,ethinodiol diacetate 1 mg).

2. Ovulen 50 administration led to a fall in serum folate levels which occurred very rapidly during the first 6 months and more slowly thereafter, stabilizing at 2·2 ng/ml in women of very low economic status and at 2·9 ng/ml in the more privileged.

3. There was a steady fall in serum folate concentrations during pregnancy, the levels at the end of pregnancy being higher than those in women under OC treatment for 9 months.

4. The need for folate supplementation during OC treatment is stressed.
A comparison of the influence on plasma lipids and platelet function of supplements of ω3 and ω6 polyunsaturated fatty acids
Authors: Sanders T. A. B. , Hochland Michele C.
Published: June 2005

1. A randomized double-blind crossover trial was carried out to compare the influence on plasma lipid concentrations, platelet thromboxane B2production and platelet aggregation induced by ADP, collagen and U46619 (a prostaglandin endoperoxide analogue), of a daily 10 g supplement of a fish-oil concentrate (MaxEPA), which provided (g): 1·7 20:5ω3, 0·3 22:5ω3 and 1·2 22:6ω3, taken for 2 weeks by ten healthy subjects, with one of vegetable oil providing 3·4 18:2ω6.

2. A lower response to platelet aggregation induced by 0·5 μg collagen/ml but not by other aggregating agents was observed following both types of supplement. Platelet thromboxane B2production induced by collagen also tended to be lower following the supplements.

3. Plasma total cholesterol concentrations were unaffected by the supplements. The MaxEPA but not the vegetable-oil supplement lowered the concentration of plasma triglycerides and increased that of high-density-lipoprotein-cholesterol.