bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of dietary sucrose and the concentrations of plasma urea and rumen ammonia on the degradation of urea in the gastrointestinal tract of cattle
Authors: Kennedy P. M.
Published: June 2005

1. The rates of entry of urea into plasma, of urea degradation in the gastrointestinal tract, and the partition of that degradation between the rumen and post-ruminal tract were determined by use of [14C]urea and NaH14CO3 in Hereford steers receiving hay diets with or without sucrose. The concentrations of plasma urea and rumen ammonia were varied by infusions of urea into the rumen or abomasum.

2. For all diets, plasma urea concentration was related to urea entry rate, to degradation of urea in the whole gastrointestinal tract, and to its degradation in the post-ruminal tract, but the relationship with its degradation in the rumen was poor.

3. Degradation of urea in the rumen was related in a multiple regression in a curvilinear manner in three groups of diets (pasture-hay alone, pasture-hay–lucerne (Medicago sativa) mixtures, diets with sucrose), and negatively to rumen ammonia concentration for pasture-hay diets, and diets with sucrose.

4. Ruminal clearance of urea (rate of urea degradation per plasma urea concentration) was negatively related to the rumen ammonia concentration for steers given diets with sucrose, of pasture-hay with or without urea infusions. Provision of sucrose in the diet significantly increased clearance.

5. Enhanced urea degradation in the rumen associated with dietary sucrose supplements accounted for 0.4 of additional microbial N synthesis in the rumen.

6. The partition of transfer of urea to the rumen via saliva and through the rumen wall is discussed.
Cold exposure and mammary glucose metabolism in thelactating goat
Authors: Faulkner A. , Thomson E. M. , Bassett J. M. , Thomsont G. E.
Published: June 2005

1. [U-14C]glucose was infused intravenously into conscious lactating goats exposed to thermoneutral or cold environments for a total of 24 h. The irreversible loss of glucose from the whole body and uptake of glucose by the mammary gland was measured and glucose utilization in the udder was studied by measuring the incorporation of radioactivity into carbon dioxide in mammary venous blood, into milk lactose and milk triglyceride-glycerol.

2. Exposure to cold increased the circulating level of glucose and slightly, though not significantly, increased the non-mammary irreversible loss of glucose.

3. The extraction of glucose from the circulation by the udder fell, the secretion of lactose by the udder also fell and this correlated closely with the reduced secretion of milk in the cold.

4. Simultaneous measurements of the concentrations of insulin, growth hormone and corticosteroids in the arterial plasma were made.

5. The plasma concentration of corticosteroids increased significantly in the cold.

6. It is concluded that reduced glucose uptake and lactose synthesis by the udder are important factors which reduce milk secretion during cold exposure.
Refection in rats fed on a sucrose-based, riboflavin-deficient diet
Authors: Prentice A. M. , Bates C. J.
Published: June 2005

1. Refection, resulting in an increased supply of riboflavin to riboflavin-deficient rats through coprophagy, was demonstrated on a sucrose-based diet when sensitive biochemical tests of riboflavin status were employed: these included measurements of NAD(P)H2:glutathione oxidoreductase (EC1.6.4.2); succinate:(acceptor) oxidoreductase (EC1.3.99.1) and NADH:(acceptor) oxidoreductase (EC1.6.99.3).

2. The use of tail-cups to eliminate coprophagy, and hence refection, resulted in a more rapid and reproducible progress into severe deficiency.

3. The occurrence of refection on a sucrose-based diet may account for hitherto unexplained differences between previous publications on the biochemical effects of riboflavin deficiency.
Endocrine control of energy metabolism in the cow: the effect on milk yield and levels of some blood constituents of injecting growth hormone and growth hormone fragments
Authors: Bines J. A. , Hart I. C. , Morant S. V.
Published: June 2005

1. Circulating concentrations of some hormones and metabolites and nitrogen balance were measured in lactating beef and dairy cows given daily injections of growth hormone (GH) and were compared to values before injection. Changes in milk yield and composition were recorded in these cows and in additional cows injected with GH fragments.

2. GH, but not GH fragments, raised milk yield while milk composition did not change. GH injection caused a large, rapid increase in the level of the hormone in blood and slower, smaller increases in the concentrations of insulin, prolactin and thyroxine. Blood metabolite levels were unaltered except for a rise in glucose concentration in beef cows during GH injection and a fall in 3-hydroxybutyrate concentration in the same cows after the injections ceased. An increase in N output in milk was partly balanced by a reduction in urinary N so that N retention did not change significantly.

3. GH caused a reduction in food intake in the beef cows.

4. The results are discussed in relation to control of partition of nutrients in the lactating cow, where GH is considered to play an important role. It was concluded that this role may be in increasing the supply of energy metabolites for milk synthesis, rather than a direct effect on the activity of the mammary gland.
The effect of feeding sugar-beet silage and non-protein-N on rumen and blood metabolites in bulls
Authors: Kulasek G. , Barej W. , Leontowicz Hanna , Krasicka Barbara , Chomyszyn M. , Zawitkowski J.
Published: June 2005

1. The purpose of the experiments was to determine certain properties of the metabolism of nitrogen compounds and carbohydrates in the rumen and tissues of growing bulls which were given either a diet containing sugar-beet silage, a urea-mineral preparation and hay or a control diet with maize silage, ground barley and hay. Daily rations were given in two equal portions twice daily at 07.00 hours and 13.00 hours. The experiment lasted 182 d.

2. The experimental diet containing 0.54 g urea and 5.0 g saccharose/kg body-weight did not cause any symptoms of toxicity in the animals although there were large changes in the concentration of metabolites in the forestomach. The lowest pH (6.2–6.4) in the rumen of animals in the experimental group was observed 1.5 h after feeding. At the same time the highest level of lactic acid was observed, but the highest level of volatile fatty acids (VFA) was observed 3 h after feeding. Although there was a large increase in ammonia in the rumen contents (approximately 20 mmol/l at 1.5 h after feeding) an increase in the blood level of ammonia was not observed.

3. A lower level of acetic acid and higher level of butyric acid and valeric acid were observed in the rumen of animals given sugar-beet silage than in animals given maize silage and ground barley. Non-glucogenic ratio of VFA in the rumen of bulls after feeding the experimental diet was approximately 3.5 while on the control diet the value was considerably higher.

4. The causes of the low concentration of glucose in the blood and changes in other metabolites in the blood of experimental animals are discussed.

5. Average daily gains were higher (P≤ 0.05) in both groups of bulls given a diet containing sugar-beet silage and NPN (1087 and 1043 g/d) than with the control diet (887 g/d). Changes in the concentration of metabolites in the rumen contents and blood of sugar-beet-silage-fed bulls confirmed the possibility of effective addition of urea in an amount corresponding to 50% of the N content and also indicated good utilization of the energy in this diet.
The role of methionine and vitamin B12in folate incorporation by rat liver
Authors: McGing P. G , Scott J. M.
Published: June 2005

The decreased folate uptake induced by exposure of rats to nitrous oxide can be partly reversed by methionine supplementation. This is consistent with the theory that N2O inhibits methylcobalamindependent methionine synthetase (EC2.1.1.13) in rat liver and previous observations showing decreased folate incorporation in rats made nutritionally vitamin B12deficient.
Studies on diurnal variations of heat production and the effective lower critical temperature of early-weaned pigs under commercial conditions of feeding and management
Authors: McCracken K. J. , Caldwell B. J.
Published: June 2005

1. The heat production of groups of pigs, weaned at 10 d of age, was determined in an open-circuit respiration chamber at various ages between 10 and 33 d at temperatures above and below the lower critical temperature (Tcl).

2. The heat production was lowest on the second or third day post weaning when pigs were given feed increasing by 25 g/pig per d from day 2. There was a marked diurnal pattern in heat production, the lowest values being recorded between 24.00 and 08.00 h.

3. The mean thermal conductance (H/ΔT, kJ/h per m2 per °ΔT, where His total heat production, m2 is the surface area calculated as 0.097 W kg0.633 (Brody, 1945) and °ΔTis the difference between rectal temperature, taken as 39°, and air temperature) below Tcl was calculated as 18.0, 16.9, 18.5 and 21.2 respectively at 10, 17, 24 and 31 d of age. Maximum values of H/ΔT obtained during feeding periods were. on average, 4.5 kJ/h per me per °ΔT higher than the mean values.

4. The maximum value for Tcl during the immediate post-weaning period was 25.9°. The mean Tcl at 17, 24 and 31 d were respectively 21.7, 18.4 and 18.6° for pigs fed almost to appetite.
The influence of molybdenum on the copper metabolism of the rat at different Cu levels of the diet
Authors: Nederbragt H.
Published: June 2005

1. Male WAG/Cpb inbred rats fed on rations with approximately 1–5rng copper/kg (deficient), 6.0 mg Cu/kg (adequate) and 25.0 mg Cu/kg (excess) were supplemented with varying amounts of molybdenum (0, 50, 150 and 500 mg/kg diet) and the effect on the Cu concentration of blood, plasma, liver and kidney, the caeruloplasmin activity of plasma and the Mo concentration of liver and kidney were studied.

2. Mo increased the Cu concentration of blood, plasma, liver and kidney and the Mo concentration of liver and kidney.

3. In the plasma of Mo-supplemented rats the presence of a Cu-containing fraction was demonstrated, the Cu of which did not react with dithiocarbamate and was not related to caeruloplasmin. The Cu in this fraction was not able to increase the caeruloplasmin activity in the plasma of Cu-deficient Mo-supplemented rats. The Cu concentration of the erythrocytes did not seem to have been increased by the Mo treatment.

4. When compared to Cu-adequate rats the effect of Mo on the Cu distribution was reduced both by Cu deficiency and Cu excess. This decreased effect of Mo was explained by reduced uptake or retention of MO in the body as observed in the liver and kidney.
The effect of iron-deficiency anaemia on two indices of nutritional status, prealbumin and transferrin
Authors: Delpeuch F. , Cornu A. , Chevalier P.
Published: June 2005

1. Serum prealbumin, transferrin and iron concentrations were measured in ninety-two north Cameroonian children under 5 years of age. The results were grouped according to the blood haemoglobin concentration range in order to show the interactions of anaemia with prealbumin and transferrin concentrations.

2. Transferrin concentration showed a significant negative correlation with serum Fe and percentage saturation of transferrin values. Prealbumin concentration showed a significant direct correlation with haemoglobin but did not correlate with either serum Fe or percentage saturation of transferrin.

3. It is concluded that in regions where Fe-deficiency anaemia is endemic transferrin concentration may be of little value in determining nutritional status. On the contrary, prealbumin seems to be more useful.
Dietary ascorbic acid and muscle carnitine (β-OH-γ-(trimethylamino) butyric acid) in guinea-pigs
Authors: Hughes R. E. , Hurley R. J. , Jones Eleri
Published: June 2005

Tissue ascorbic acid (AA) contents of approximately 12 and 100% saturation respectively were produced in two groups of guinea-pigs. The ‘low-AA’ group had significantly lower muscle carnitine concentrations than the ‘high-AA’group. There was no concomitant emergence of the symptoms customarily regarded as characteristic of hypovitaminosis C. It is concluded that muscle carnitine (β-OH-γ-(trimethylamino) butyric acid) is a highly-sensitive indicator of tissue AA contents; this could account for the lassitude and fatigue reported to precede the emergence of frank scurvy in man.
Estimation of in vivo digestibility with the laying hen by an in vitro method using the intestinal fluid of the pig
Authors: Sakamoto K. , Asano T. , Furuya S. , Takahashi S.
Published: June 2005

1. Dry matter and crude protein (nitrogen × 6.25) digestibility of four poultry diets determined by an in vitro method using the intestinal fluid of pigs was significantly correlated with corresponding in vivo digestibility values obtained with hens.

2. The intestinal fluid could be lyophilized and stored for at least 35 d without losing its activity on digestion.
The early changes in retinol-binding protein and prealbumin concentrations in plasma of protein–energy malnourished children after treatment with retinol and an improved diet
Authors: Large Suzanne , Neal G. , Glover J. , Thanangkul O. , Olson R. E.
Published: June 2005

1. Changes in total retinol-binding protein (RBP), the holoprotein (holoRBP) and prealbumin (PA) concentrations have been monitored in plasma of thirty protein- and vitamin A-deficient preschool children from within a few hours up to 7 weeks after treatment with retinol and a good-quality protein diet.

2. The children were classified into groups according to nutritional status as having either kwashiorkor, marasmus-kwashiorkor or marasmus, and given formula diets whose protein and energy contents increased stepwise from 1 g and 105 kJ/kg body-weight respectively up to 4 g and 733 kJ/kg body-weight after 4 weeks. Retinol was administered in the forms of retinyl palmitate either orally or intramuscularly.

3. PA and total RBP were determined by electroimmunoassay procedures and the holoRBP by its fluorescence after separation from other plasma proteins.

4. RBP in plasma of the vitamin A-deficient child is largely denatured and incapable of binding administered retinol, which must first be taken up by the liver before native holoRBP is released. An increased pool of native apoprotein accumulates in the liver during vitamin A deficiency which is released into plasma quickly after retinol uptake to form peak concentrations of total and holoRBP approximately 3 h after dosing intramuscularly and 6 h orally.

5. The accumulated pool of RBP was highest in livers from the marasmus group and lowest in those from the kwashiorkor group, reflecting their relative capacities to synthesize plasma proteins.

6. The mean plasma concentrations of total and holoRBP for the various groups were minimal 24–48 h after dosing with retinol and then improved almost linearly over the following week.

7. Mean plasma PA concentrations of the various groups on admission were also in order of the severity of their malnutrition. There was little or no change in this protein concentration over the first 24 h after dosing with retinol, but thereafter the mean values rose almost linearly over 2 weeks. Albumin on the other hand changed little during the first week. The results show that PA is the more sensitive measurement of protein nutritional status.
Phosphopeptides and soluble calcium in the small intestine of rats given a casein diet
Authors: Lee Yeon Sook , Noguchi T. , Naito H.
Published: June 2005

1. Semi-synthetic diets containing 200 g protein/kg were meal-fed for 1.5 h to groups of rats. The contents of the whole small intestinal tract were collected and the amount of soluble calcium was determined.

2. In the rats given 200 g casein/kg diet, formation of a fraction containing macrophosphopeptide in the small intestine was confirmed by gelfiltration of the intestinal contents on Sephadex G-25. However, this macrophosphopeptide fraction was not found when casein alone was fed.

3. In the intestinal contents at 2.5 h after ingestion, the amounts of both soluble Ca and phosphorus were significantly higher in rats fed the casein diet than in those fed diets containing egg albumin, isolated soyabean protein or an amino acid mixture. However, the amount of insoluble Ca was least in rats fed the casein diet.
A simple procedure using35S incorporation for the measurement of microbial and undegraded food protein in ruminant digesta
Authors: Mathers J. C. , Miller E. L.
Published: June 2005

A simple procedure using35S incorporation for the measurement of microbial protein in abomasal or duodenal digesta of ruminants was developed and tested.

Microbial protein synthesized in the rumen was labelled with35S by intraruminal infusion of35SO4and a microbial fraction was isolated by differential centrifugation.

35S not bound by micro-organisms and present as inorganic35S in whole digesta and in microbial fractions was oxidized to35SO4and the samples were brought into solution by acid-hydrolysis.35SO4was precipitated as Ba35SO4.

The proportion of microbial non-ammonia-nitrogen (NAN) in digesta NAN was determined as35S:NAN (digesta) ÷35S:NAN (microbial).

In sheep offered grass nuts at maintenance level of feeding, 48% of NAN flowing through the abomasum was of microbial origin. NAN flow to the small intestine was estimated using chromic oxide as a marker and it was calculated that 49% of the grass N was degraded in the rumen.
Effects of withdrawal of copper sulphate from the diet of the mature domestic fowl with special reference to production and tissue mineral content
Authors: Stevenson Mary H , Jackson N.
Published: June 2005

1. Cereal-based diets containing 0, 500, 1000 or 2000 mg added copper/kg were offered ad lib. to laying hens for 8 weeks. All the hens were subsequently offered the control diet (no added Cu, 7.5 mg Cu/kg).

2. Hens from each treatment were killed at 0, 2, 4, 6 and 8 weeks after removal of the Cu-supplemented diets. Records were kept of body-weight, food consumption and egg production.

3. After slaughter, blood haemoglobin, packed cell volume, serum Cu and aspartate aminotransferase (AAT; EC 2.6.1.1) were assayed. The liver, kidneys, oviduct, ovary, gizzard, caeca and bile duct were weighed.

4. Mean Cu, zinc and iron concentration of liver, kidneys and caecal contents were determined.

5. The adverse effects of Cu on body-weight, food intake, egg production and liver, oviduct, ovary, gizzard and bile weights were rapidly reversed by removal of added Cu from the diets.

6. Greatly enhanced liver Cu concentration resulted from feeding the high-Cu diets but this effect was rapidly reversed on removal of added Cu from the diets. Liver Fe concentration showed a less marked but similar effect.

7. The Cu concentration of caecal contents was increased by Cu supplementation and rapidly reduced after withdrawal of the Cu-containing diets.
Energy expenditure of male farmers in dry and rainy seasons in Upper-Volta
Authors: Brun Thierry , Bleiberg Fanny , Goihman Samuel
Published: June 2005

1. Thirty Mossi male farmers from Upper-Volta were investigated, twenty-three in the dry season (March-April) and sixteen in the rainy season (July-August), eight of them being studied twice. A 48 htime-and-motion study was carried out and the daily energy expenditure was computed.

2. The mean height was 1.70 m and the mean weight 58.5 kg. The average percentage of body fat calculated from skinfold thickness was 10.

3. During the dry season the subjects could be classified as very moderately active with an energy output of 10.1 MJ (2410 kcal)/d. By contrast, with an energy expenditure of 14.4 MJ (3460 kcal)/d, they were considered as exceptionally active in July-August when performing the agricultural work.

4. In this study we measured the intensity of physical work in a society where human labour is still the main tool of production. The determination of seasonal variations in energy expenditure may be useful to assess the nutritional requirements in arid zones of West Africa.
An examination of factors which may affect the water holding capacity of dietary fibre
Authors: Robertson J. A. , Eastwood M. A.
Published: June 2005

1. Dietary fibre has a water holding capacity (WHC) and this is a function of the fibre source and method of measurement. Water can be associated with fibre either as trapped water or bound water. This makes it difficult to predict the ability of fibre to influence stool weight in humans.

2. Examination of various fibre concentrates for chemical composition, as neutral detergent fibre (NDF), acid detergent fibre (ADF) and lignin; structure, by scanning electron microscopy; WHC, by centrifugation, suggests that WHC is more a function of fibre structure than chemical composition. Cereal fibre and vegetable fibre have a different chemical composition and are structurally very distinct. Structure is also dependent on the method of fibre preparation.

3. Measurement of WHC by centrifugation gives an estimate of the water which can be bound and also trapped by the fibre. The amount of trapped water will depend on the structure of the fibre whereas bound water will depend on the chemical composition.
Energy intakes on sledging expeditions
Authors: Campbell I. T.
Published: June 2005

1. Previous measurements of energy intake on sledging journeys in Antarctica have given a mean intake of 14.2 MJ (Acheson, 1974; Campbell, 1975), markedly lower than values reported earlier (see Edholm & Goldsmith, 1966). The technique used (individual weighed-diet survey) was more detailed and could be assumed to be more accurate than most of the earlier work where intakes had been largely inferred from the known energy content of food boxes. In the present study an individual weighed-diet survey was carried out on male subjects during a summer manhauling journey on the east coast of Greenland.

2. Mean daily energy intake of six subjects over 33 d travelling was 16.5 MJ. Mean weight loss was 2.3 kg, probably accounted for entirely by fat loss. Weight loss occurred despite the presence of excess food. Mean daily energy intake rose gradually but persistently over the 5 weeks of the journey despite a constant level of activity and to 20.1 MJ during the 4 d rest at the end of the journey.

3. Intakes were thus higher than those found in the earlier Antarctic studies (Acheson, 1974; Campbell, 1975) but not as high as intakes reported previously (see Edholm & Goldsmith, 1966). The fact that weight loss occurred despite the presence of excess food was ascribed to the monotonous nature of the diet. The fact that energy intake rose persistently over the 5-week study period may imply that a new state of balance of intake and expenditure was reached.
A study of the effects of dietary added cupric oxide on the laying, domestic fowl and a comparison with the effects of hydrated copper sulphate
Authors: Jackson N. , Stevenson Mary H.
Published: June 2005

1. An experiment is reported in which copper, as cupric oxide, was fed to two breeds of laying hen for 336 d at levels equivalent to 150, 300, 450, 600 and 750 mg added Cu/kg diet. The results obtained were compared with those found using similar diets to which the Cu was added as CuSO4. 5H2O.

2. Addition of the CuO had no effect on food intake, food conversion efficiency, body-weight or egg production. The CuSO4addition caused the quadratic response of food intake and the adverse effects on food intake, egg production and body-weight noted in previous experiments.

3. The CuO had no effect on liver, kidney, ovary, oviduct or gizzard weight per unit body-weight while the CuSO4decreased these with the exception of gizzard weight which was significantly increased.

4. CuO addition did not affect liver Cu concentration but CuSO4caused a subtantial increase of liver Cu especially at the 750 mg Cu/kg level of addition.

5. CuO addition had no effect on liver lipid concentration but this was depressed at the highest level of CuSO4addition. Effects on individual fatty acids are presented but no specific conclusions have been reached.
Diabolic acids: occurrence and identification in natural products and their metabolism by simple-stomached and ruminant animals
Authors: Hazlewood G. P. , Northrop A. J. , Dawson R. M. C.
Published: June 2005

1. A method for gas-liquid chromatographic analysis of the dimethyl esters of a homologous series of diabolic acids is described.

2. Only when combined with low-resolution mass spectrometry could the method be used to show unequivocally the existence of diabolic acids in natural products.

3. Diabolic acids occurred naturally in rumen and faecal lipids of all ruminants examined but could not be detected in a number of ruminant tissue samples.

4. Infused14C-labelled (C16:0)2diabolic acid was poorly absorbed by both simple-stomached and ruminant animals. Oxidation was more extensive in the ruminant, but there was no evidence of deposition of diabolic acid in the tissues of either animal.
The digestibility of amino acids in the small intestine of the sheep
Authors: Tas M. V. , Evans R. A. , Axford R. F. E.
Published: June 2005

1. The digestibilities of microbial and food proteins in the small intestine were studied in three sheep fitted with re-entrant cannulas in the proximal duodenum and terminal ileum.

2. The quantities of microbial and food proteins at the small intestine were varied by infusion of a microbial isolate or by dietary manipulation and the balance of amino acids along the small intestine was determined.

3. A mean value of 0.69 for the apparent digestibility and 0.86 for the true digestibility of total amino acids was obtained.

4. From the composition of digesta at the duodenum the daily flows of microbial and food proteins were estimated. Their true digestibilities in the small intestine were calculated by regression and found to be: microbial protein 0.87 and food protein 0.82. The mean endogenous loss of amino acids secreted into the small intestine was estimated to be 13.3 g/d.
Factors affecting the voluntary intake of food by sheep
Authors: Grovum W. L.
Published: June 2005

1. Sheep given ground and pelleted lucerne hay (Medicago sativa)ad lib.were infused intravenously with pentagastrin, secretin, cholecystokinin (CCK) and its analogues to assess their effects on motility of the reticulo-rumen and on food intake. In the latter experiments the animals were deprived of their diet for periods of up to 6 h to induce hunger and the infusions were made before and during 3–10 min periods of feeding.

2. Pentagastrin, an analogue of gastrin, depressed intake by 35–50% (P< 0.05) when it was infused at 9 μg/kg per h during 30 min of feeding. The threshold may however be below 1 μg/kg per h as this dose decreased intake of 12–17%. The frequency of reticular contractions decreased by 13, 35, 39 and 44% when 1, 3, 9 and 27 μg pentagastrin/kg per h respectively was infused (P> 0.025).

3. Secretin depressed food intake 38% after 30 min (P> 0.025) when 8 Clinical Units (CU)/kg per h was infused but the threshold could be less than this dose since 0.5 CU/kg per h depressed intake by 12%. Contraction amplitude but not frequency decreased at 8 CU/kg per h.

4. CCK produced a 39% decrease in intake during the first 10 min of feeding (P< 0.05) and the threshold was between 5 and 15 Ivy Dog Units (IDU) or 425 and 1276 pmol/kg per h. The frequency of reticular contractions was not affected by 1.7 IDU/kg per h but it was depressed 21 and 63% by 5 and 15 IDU/kg per h. Octapeptide at 1.5 and 3 μg (1312 and 2624 pmol)/kg per h depressed intake by 11 and 43% respectively after 10 min (not significant) and 1.5 μg/kg per h depressed motility by 39% (P< 0.01). Ceruletide at 810 ng (599 pmol)/kg per h depressed intake by 31% (not significant) after 10 min and decreased motility by 52% (P> 0.05). The threshold dose for ceruletide on intake appeared to be about 90 ng or 66 pmol/kg per h which is considerably less than that for CCK or octapeptide.

5. The biological significance of gastrointestinal hormones as signals of satiety in normal sheep is not known since doses of pentagastrin and CCK that suppressed intake also interfered quite markedly with motility. However there is good reason to suspect that elevated concentrations of gastrin and CCK in blood of parasitized sheep may account at least in part for their symptoms of rumen atony and reduced food intakes.
Effect of different levels of dietary molybdenum on copper and Mo metabolism in sheep fed on high levels of Cu
Authors: Ryssen Van , W. J. Stielau
Published: June 2005

1. Distribution of copper and molybdenum was followed in the body tissues of sheep fed on high levels of Cu (82 mg Cu/sheep per d), sulphur (3·77 g S/sheep per d) and different levels of Mo (0·6 20·8, 38.4 and 58.5 mg Mo/sheep per d).

2. Liver Cu content decreased as Mo intake increased from 0.6 to 38.4 mg/d, but increased again at high intakes of Mo. With an Mo intake of 58.5 mg/d, the Cu content of liver, kidney, lung, spleen and muscle tissue was significantly higher than with an intake of 20.8 mg Mo/d. The trend of increased Cu concentrations in kidneys and plasma was already evident at an Mo intake of 38.4 mg/sheep per d.

3. High positive correlations were observed between Cu and Mo in both the kidney cortex and medulla of the sheep at the two highest Mo treatments.

4. At constant S intake, Mo concentrations in the tissues tended to increase in proportion to Mo intakes. No indication of any detrimental effect due to the accumulation of Mo in the tissues was observed.

5. It was suggested that in the presence of an abundance of Mo, Cu and S, compounds containing these minerals in metabolically unavailable forms accumulate in the body, first in the kidneys, but eventually also in the other tissues of the sheep.
Effects of overfeeding by gastric intubation on body composition of adult female rats and on heat production during feeding and fasting
Authors: McCracken K. J. , McNiven Mary A.
Published: June 2005

1. The effects of overfeeding by gastric intubation on the body composition and energy metabolism of adult female rats were studied in three experiments.

2. In Expt 1 there were significant (P < 0·001) linear increases in carcass dry matter, fat and energy during a 10 d period as metabolizable energy (ME) intake was increased from 160 to 300 kJ/d.

3. In Expt 2 rats were fed to maintain weight (130 kJ/d) or given approximately 270 kJ/d for 120 d. Measurements of fed and fasting heat production (FHP) were made at intervals. FHP (kJ/d per kg metabolic weight (W0·75)) decreased by 15% over the 120 d period on both treatments. The mean carcass weight of the overfed rats increased from 216 to 465 g, over 90% of the increase being due to fat.

4. In Expt 3 rats were fed to maintain weight (137 kJ/d) or given approximately 300 kJ/d for 6, 12, 18, 24 or 30 d. There were significant linear increases (P < 0·001) with time in carcass weight, dry matter, fat and energy. FHP, measured before slaughter, increased from 118 to 160 kJ/d but remained constant at 334 kJ/d per kg W0·75.

5. In all three experiments there were significant (P < 0·01) increases in carcass crude protein (nitrogen × 6·25) in response to overfeeding.

6. The efficiency of utilization of energy for production (Expt 1) or for maintenance and production (Expts 2 and 3) averaged 0·92, 0·86, 0·88 respectively.

7. It is concluded that FHP per kg W0·75 may be regarded as constant over a wide range of body compositions in adult rats made obese by gastric intubation, and that energy utilization conforms to classical concepts.
The influence of protein:energy value of the ration and level of feed intake on the energy and nitrogen metabolism of the growing pig
Authors: Close W. H. , Berschauer F. , Heavens R. P.
Published: June 2005

1. The heat losses and energy and nitrogen balances of thirty-six individually-housed, entire male pigs (initial body-weight 18–30 kg) were measured over 7 d periods, when they were fed on rations containing 153, 201 and 258 g crude protein (nitrogen × 6·25; CP)/kg dry matter (DM). The rations also contained 16·29, 16·96 and 17·24 MJ metabolizable energy (ME)/kg DM so that the CP:ME values were 9·4, 11·8 and 15·0 g CP/MJ ME respectively. Each ration was given at three levels, 20, 35 and 50 g feed/kg body-weight per d, thus giving nine dietary treatments. The experiments were carried out at an environmental temperature of 22 (±1)°.

2. Heat loss (H) increased significantly (P < 0·01) with increase in ME intake. The rate of increase in H was not, however, influenced by the protein content of the ration. Thus, energy retention (ER) at any given level of ME intake was independent of the ration offered. From the relationship between ER and ME, estimates of the maintenance energy requirement (MEm) and the partial efficiency of energy utilization (k) were determined. MEm varied within the range 494–568 kJ/kg body-weight0·75 per d, while k varied from 0·70 to 0·76.

3. Both energy and protein intakes had a significant influence upon the rates of protein (P) and fat (F) deposition, and hence body-weight gain. At any given level of feed intake P was higher and F lower the higher the protein content of the ration. However, when compared at similar levels of protein intake, both P and F were reduced the higher the protein content of the ration.

4. From the multiple regression equations relating P and F to ME, individual estimates of MEm and the energetic efficiencies of protein (kp) and fat (kF) depositions were determined. Using an overall mean kF value of 0·86, it was calculated that MEm ranged from 462 to 525 kJ/kg body-weight0·75 per d while kp varied from 0·48 to 0·55. The significance of these estimates of kp are discussed in the light of their derivations and in relation to theoretical values.
Nutritional ocular diseases and their association with diarrhoea in Matlab, Bangladesh
Authors: Khan Moslem Uddin , Haque MD. Emdadul , Khan Matiar Rahman
Published: June 2005

1. The prevalence of visual defects, especially from causes associated with nutritional deficiencies, and their relation to diarrhoea in rural Bangladesh have been studied. A trained physician and a team of health workers examined visual defects in 149 villages, with a total population of 182976.

2. According to WHO classification, night blindness (XN) was found in only 0.03 persons/1000 population and 0.04 were found to have conjunctival xerosis (XIA) and Bitot's spot (XIB). Corneal xerosis (X2, X3A, X3B) also was found in 0.04 persons/1000. Night blindness combined with conjunctival xerosis and Bitot's spot (XN + XIA + XIB) was present in 1.69 persons/1000 and all combined stages of active xerophthalmia were seen in 0.06 persons/1000. Xerophthalmia prevailed up to age 19 years. Males had a significantly higher (2.9) incidence/1000 than did females (1.2).

3. The total rate of keratomalacial scar for all ages was 0.31 persons/1000, while corneal opacity from other causes was seen in 2.25 persons/1000 population.

4. More than 2.06 persons/1000 had ocular manifestations of one or more vitamin A deficiencies, while 4.47 persons/1000 had other ocular diseases, except for cataracts.

5. Only 12.0% of all the corneal scars (XS) were due to keratomalacia.

6. History of night blindness is a good indicator of vitamin A deficiency. In 96% of cases, night blindness was associated with conjunctival xerosis and Bitot's spot (XN + XIA + XIB).

7. The onset of approximately 86% of cases of corneal xerosis (X2, X3A, X3B) and night blindness associated with conjunctival xerosis and Bitot's spot (XN + XIA + XIB) was related to diarrhoea.
The development of cold-induced thermogenesis and the structure of brown adipocyte mitochondria in genetically-obese (ob/ob) mice
Authors: Hull D. , Vinter J.
Published: June 2005

1. The onset of cold-induced thermogenesis was studied in a strain of mice which produced among their offspring genetically-obese (ob/ob) individuals. A thermogenic response was present in a majority by day 5 after birth.

2. The thermogenic response to cold was measured on days 5, 10 or 15 after birth, and the animals reared and the onset of obesity noted. The correlation between the subsequent development of obesity and a poor thermogenic response in early life was low.

3. A poor thermogenic response at day 15 was associated with the presence in brown adipocytes of mitochondria with disordered internal structures.

4. At day 42 both non-obese and obviously-obese mice showed a similar thermogenic response to moderate cold exposure.

5. It would seem that in this strain of mice disordered internal mitochondria1 structure in brown adipose tissue is associated with a poor thermogenic response to cold, but not invariably with the subsequent onset of obesity.
Chromium in human milk from American mothers
Authors: Casey Clare E. , Michael Hambidge K.
Published: June 2005

1. The chromium concentration was determined in 261 samples of breast milk collected by manual expression from forty-five American women.

2. Cr was measured in whole, liquid milk by graphite-furnace atomic absorption spectrophotometry, using the method of standard additions.

3. The mean Cr content of the breast milk samples was 0.30 ng/ml. The range of individual values was 0.06–1.56 ng/ml and did not change significantly with duration of lactation.

4. The Cr content of breast milk from these American women is similar to levels reported recently in milk from Finnish women.
Abomasal emptying in sheep as related to the amount of protein entering the abomasums
Authors: Bruchem J. Van , Van Der Lende T. , De Swart J. G. , Bangma G. A.
Published: June 2005

1. In sheep, provided with re-entrant cannulas in the caudal duodenum and with an infusion tube into the abomasal fundus, emptying of the liquid phase of the abomasal contents was studied with [57Co]EDTA. Radioactivity was measured continuously with Geiger-Müller counters placed along the re-entrant cannulas.

2. It appeared that first-order kinetics could be applied to the elimination of [57Co]EDTA from the abomasum. Mean retention time of this label in the abomasum was 40–50 min.

3. Infusion of a suspension of soya-bean protein in saline (9 g sodium chloride/l) caused an initially decreased rate of abomasal emptying, but after 48 h an adaptation had occurred to the original rate of emptying producing an increased volume of abomasal contents and increased flow-rate of digesta into the duodenum.
The voluntary food intake by growing pigs of diets containing ‘treated’ rapeseed meals or extracts of rapeseed meal
Authors: Lee Pauline A. , Pittam Sharon , Hill R.
Published: June 2005

1. The intake by growing pigs of a diet containing British rapeseed meal (Brsm) extracted once with water was greater than that of a similar diet containing untreated Brsm, and a diet containing Brsm extracted twice with water was eaten more readily than one containing Brsm extracted once with water. Treatment of Brsm with slaked lime increased slightly its acceptability by growing pigs.

2. The addition of a water extract of Brsm to a soya-bean meal (Sbm) diet reduced voluntary intake compared with the voluntary intake of the same Sbm diet with water added. Addition to the diet of a water extract passed through an anion exchange column increased food intake but if a cation exchange column was used there was no effect on intake.

3. Treated rapeseed meals and extracts were analysed for glucosinolates, sinapine and tannins; the results indicated that glucosinolates rather than sinapine or tannin were associated with low feed intake.
The hydrogenation of somecis- andtrans-octadecenoic acids to stearic acid by a rumenFusocillussp.
Authors: Kemp Patrick , Lander David J. , Gunstone Frank D.
Published: June 2005

1. The hydrogenation of a range of double-bond positional and configurational octadecenoic acid isomers (cis (δ2 and δ4 to δ13) and trans (δ2 and δ5 to δ13)) to stearic acid by a rumen Fusocillus sp. were examined.

2. The cis and trans δS to δ13 isomers were all hydrogenated to some extent by late-log-phase cultures added to suspensions of individual isomers and incubated for a further 3 h. Of the cis-isomers, δ5 to δll (79–73% conversion to stearic acid) were the preferred substrates. δ24s- (30%) and δ13-cis-isomers ( 5 % ) were poorly hydrogenated. Of the trans-isomers, δ8, δ9 and δ10 were 45% converted to stearic acid, the other isomers were poorly hydrogenated. These results are in agreement with less extensive studies using sheep rumen micro-organisms.

3. When cultures were grown from small inocula in media containing individual isomers more extensive hydrogenation was found than with late-log-phase cultures. At 24 h, cis δ2, δ4 and δ5 gave the highest conversions to stearic acid (90%) followed by the cis δ6 to δ12 and trans δ8 to δ10 isomers (approximately 75%), although at 6 and 12 h δ9-trans gave higher yields of stearic acid than δ9-cis, probably because the growth of the cis cultures showed a longer log-phase.
The hydrogenation of the series of methylene-interruptedcis,cis-octadecadienoic acids by pure cultures of six rumen bacteria
Authors: Kemp Patrick , Lander David J. , Holman R. T.
Published: June 2005

1. The hydrogenation of all the methylene-interrupted cis, cis-octadecadienoic acids was examined using pure cultures of six rumen bacteria able to hydrogenate linoleic acid to stearic acid or its immediate precursor, trans-1 1-octadecenoic acid, after first conjugating the linoleic acid to cis,truns-9, 1 1-octadecadienoic acid.

2. Only the Δ 14-cis, 17-cis-isomer was not hydrogenated by at least one of the bacteria and no evidence was found that conjugation was necessary before hydrogenation except for the Δ 2-cis,5-cis- and Δ 9-cis, 12-cis-isomers. Several isomers were hydrogenated to an extent close to that achieved with linoleic acid (Δ 9-cis, 124s).

3. Those bacteria only able to hydrogenate linoleic to trans-1 1-octadecenoic acid gave only octadecenoic acid products and those bacteria able to hydrogenate linoleic acid to stearic gave variable yields of octadecenoic acids and stearic acid except with the isomers Δ 12-cis, 15-cis and Δ 13-cis, Idcis when only octadecenoic acids were detected.

4. At the substrate levels used (20 μg/ml), both inhibition and stimulation of growth were found but no common pattern emerged, nor was the growth consistently related to the extent of hydrogenation.
Measurement of short-term changes in the fat content of the body: a comparison of three methods in patients receiving intravenous nutrition
Authors: Almond D. J. , King R. F. G. J. , Burkinshaw L. , Oxby C. B. , McMahon M. J.
Published: June 2005

1. Three methods of measuring changes in body fat were compared in seventeen patients undergoing a 2-week course of intravenous nutrition. Patients received all nutrition intraveneously at a steady rate of infusion, calculated to supply energy at a rate equal to 1.5 times the resting metabolic expenditure measured before feeding. Fat change was estimated from measurements of skinfold thickness, by isotopic methods (neutron-activation analysis and dilution of tritiated water) and by daily analysis of expired gases.

2. The mean (with 1 SEM) gain in fat over the 2-week period was 1.14 (0.30) kg for skinfold measurement, 0.53 (0.62) kg for isotopic determination and 1.29 (0.22) kg for expired-gas analysis. There were no significant differences between the mean gains in fat measured by the three methods.

3. The results show that expired-gas analysis is the most sensitive technique, measuring change in fat content with an estimated precision of 0.26 kg. The isotopic method is less sensitive, with a precision of 2.38 kg, but provides a detailed description of body composition. In contrast to these highly-specialized techniques, both of which have limited application, the simple technique of measurement of skinfolds occupies an intermediate position of sensitivity, with a precision for measuring change in fat content of 0.85 kg, and also has the potential to measure total body fat content.
Response of male and female rats to undernutrition
Authors: Harris Patricia M. , Hodgson Diane F. , Broadhurst R. B.
Published: June 2005

1. In two separate trials male and female Wistar rats, 12 weeks of age, were either killed as a preliminary control group,ad lib.-fed or undernourished for 4 weeks until one-third of their 12-week body-weight was lost.

2. Food intakes, urinary and faecal collections and measurements of standard metabolic rate were made at one-weekly intervals on both thead lib.-fed and undernourished animals of both sexes.

3. The bodies of the preliminary controls, thead lib.-fed and the undernourished animals of both sexes were analysed for protein and fat, and the weights of four fat depots, two muscles and the major organs of all groups were determined.

4. Measurements of lipid synthesis rate (LSR) and lipoprotein lipase (EC 3.1.1.34) (LPL) activity in the four fat depots and measurements of whole-body protein synthesis rates were carried out on animals of both sexes in each group.

5. Although both sexes lost the same proportion of body-weight the females required more food on a body-weight basis than the males during the undernutrition period. The females absorbed significantly more energy on a body-weight basis during undernutrition and so were less efficient than the males at withstanding nutritional stress.

6. There were no significant differences between males and females, on a body-weight basis, in the excretion of nitrogenous waste products (urinary nitrogen, creatinine, hydroxyproline or NT-methylhystidine) suggesting that there were no differences between the sexes in protein sparing during undernutrition.

7. There were no differences between males and females in the proportions of body fat and protein used during the period of undernutrition or in the sites of the body from which the protein and fat were mobilized.

8. There were no differences between males and females in the way they responded to undernutrition by altering LSR, LPL activity or whole-body protein synthesis rates. Both undernourished males and undernourished females maintained synthesis of lipid, on a per g tissue basis and whole-body protein synthesis at the level found in well-nourished animals of the same sex.
Changes in serum levels of 1,25-dihydroxyvitamin D3, calcium and phosphorus with age and vitamin D status in chickens
Authors: Sedrani Saleh H.
Published: June 2005

1. The effects of vitamin D3(D3) on serum levels of 1, 25-dihydroxyvitamin D3(1, 25(OH)2D3), ionic calcium, total Ca and phosphorus in chicks were studied from the time of hatching until sexual maturity.

2. Chicks fed on a diet low in D3showed a serum level of 1, 25(OH)2D3higher than that in chicks on a normal-D3diet, for both sexes and at any given age.

3. A dramatic increase in the serum level of 1, 25(OH)2D3occurred in female birds approaching sexual maturity and in laying hens raised on the low-D3diet the level was five times that of their counterparts raised on a normal-D3diet.

4. Theserum 1, 25(OH)2D3levelin adultmalesin thelow-D3groups wasseven timesthatofthoseon thenormal-D3diet.

5. The serum level of 25-hydroxyvitamin D3remained relatively unchanged at weeks 2 and 15 in birds on a low D3intake as well as in those fed on a normal-D3diet. Nevertheless, the levels of 25-hydroxyvitamin D3were different between the two groups.

6. No significant change was observed in the level of ionized serum Ca in relation to dietary regimen, but there was an increase in total Ca concentration in females with the onset of reproduction.

7. The serum P level decreased gradually with age, reaching a minimum value 3 and 8 weeks before laying commenced in the groups on low- and normal-D3diets respectively. An increase was observed when the hens began laying.

8. Chicks adapted to a low-D3diet by elevation of their plasma level of 1, 25(OH)2D3. The mechanism by which this is achieved is not known, but the results suggest that parathyroid hormone, Ca and P are unlikely to play roles in the adaptive increase in the level of 1, 25(OH)2D3in the blood of chicks given a minimal amount of D3. The possibility that the rate of degradation of 1, 25(OH)2D3is greatly reduced under these conditions cannot be excluded and this could account for the level of this metabolite in those birds.