bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nucleic acid metabolism in the ruminant
Authors: Smith R. H. , Mcallan A. B. 
Published: June 2005

1. Concentrations of nucleic acid nitrogen and other nitrogenous constituents were estimated in digesta taken from the proximal duodenum of calves which were given, either, one of a number of stall diets or pasture. These concentrations were compared, using polyethylene glycol (PEG) as a non-absorbed marker, with corresponding concentrations in rumen fluid and ileal contents.2. There was little net change in amounts of RNA or DNA between rumen and duodenum relative to PEG, but there was a marked increase in amounts of total-N. In duodenal digesta, for any one animal given most diets, nucleic acid-N formed a fairly constant percentage (8–11 for different animals) of the total non-ammonia-N. This value was lower (by about 3) than the corresponding percentage in rumen fluid. Comparison of nucleic acid-N: total-N ratios in duodenal contents and bacteria suggested that, for these diets, about 40–55% of the non-ammonia-N in duodenal contents was of microbial origin.3. During passage of digesta between the duodenum and ileum the mean percentage disappearances of total-N, RNA and DNA were estimated to be about 67, 85 and 75 respectively. There was evidence that these values varied with the amounts of the constituents entering the duodenum.4. Ammonia was absorbed in the omasum-abomasum only when concentrations in rumen fluid were high (40 mM), but even moderate concentrations of ammonia entering the duodenum (3 mM) were efficiently absorbed (about 90%) in the small intestine.
Effect of sex hormones on fasting serum triglycerides in baboons given high-sucrose diets
Authors: Coltart T. M , Macdonald I 
Published: June 2005

1. The incorporation of [14C]sucrose in to serum triglyceride was shown to increase in both male and female baboons after a period of high sucrose intake. During the same period of high sucrose intake there was an increase in the fasting serum triglyceride concentration of the male baboons but not of the females.2. When the male baboons were given a parenteral oestrogen preparation in addition to the sucrose diet the increase in fasting serum triglycerides was greatly reduced but there was little alteration in the extent of the incorporation of sucrose into serum triglyceride compared to that with the diet and no oestrogen.3. A parenteral testosterone preparation given to the female baboons in addition to sucrose diet had no effect on either the extent of incorporation of sucrose into triglyceride the fasting serum concentrations of triglyceride.4. The findings suggest that the differing patterns of fasting triglyceride response in the male and female baboons to the sucrose diet may have resulted from oestrogen enhancing the removal of triglyceride from the serum of the female animals.
The influence of level of grain intake on protein digestion in the intestine of cattle
Authors: Neudoerffer T. S. , Leadbeater P. A. , Horney F. D , Bayley H. S 
Published: June 2005

1. Protein digestion in the gastro-intestinal tract of cattle receiving diets with either low or high content of maize was investigated. Digesta obtained from the duodenum and ileum were separated into three fractions; soluble, microbial and particulate, and the amino acid composition of the three fractions and that of the total digesta were determined. The proportion of particulate material digested in the intestine was less from the high-maize than from the low-maize diet, but more of the particulate fraction entered the duodenum from the high-maize than from the low-maize diet, so the absolute amount of particulate fraction which was digested was greater for the high-maize diet.2. More protein was digested in the rumen from the low-maize diet (high-roughage) than from the other diet. Total digestion of protein from the low-maize diet was also higher.3. Although more protein from the high-maize than from the low-maize diet reached the duodenum, the protein from the low-maize diet was more digestible in the intestine, so the total amount of dietary protein digested in the intestine was the same for both rations.
Nitrogen metabolism in sheep
Authors: Mathison G. W. , Milligan L. P. 
Published: June 2005

1.15NH4Cl was continuously infused for periods of 120–216 h into the rumens of sheep which were allowed to feed 2 out of every 10min. These treatments achieved steady metabolic states and allowed the assessment of nitrogen conversions by means of tracer methodology. The sheep were given either a barley diet or one of three hay diets. In two trials, the flow of abomasal material was determined using lignin and polyethylene glycol as markers. The amounts of dry matter (DM), gross energy, total N, soluble N, microbial N and microbial DM in abomasal digesta, and the concentration of ammonia in the rumen liquor were measured. The concentrations of15N in the N of urine, faeces, rumen and abomasal bacteria and protozoa, rumen and abomasal bacterial and protozoal protein, abomasal particulate matter and in rumen ammonia were determined.2. Comparisons of the steady-state concentrations of15Nin the microbes with that in rumen ammonia indicated that from 50 to 65% of the bacterial N and from 31 to 55% of the protozoal N were derived from rumen ammonia in vivo.3. An amount of N equivalent to 60–92% of the daily intake was transformed into ammonia N in the runen.4. Some 17–54% of the ammonia was absorbed from the rumen, but this was not readily converted into urea.5. Microbial growth in the rumen resulted in the assimilation of 1.7–2.6 g N/100 g DM fermented.6. The generation-time of bacterial protein in the rumen was calculated from the rate of in- crease of15N concentration in this fraction, and values of 38 and 42 h were obtained for sheep given barley and hay diets respectively.7. The combined results allowed quantitative estimates to be made of the complete metabolism of rumen N, and from these the possibility of fixation of N gas in the rumen was suggested.
Composition of human adipose tissue from deep and subcutaneous sites
Authors: BROOK C. G. D. 
Published: June 2005

1. Adipose tissue was obtained simultaneously from subcutaneous and deep sites in children undergoing elective surgery, and from different subcutaneous sites in adults. The lipid content and fatty acid composition were measured using gas-liquid chromatography and the number of cells counted after fixation in osmium tetroxide. The mean amount of lipid per cell was used as a measure of the size of the cells.2. Cells from deep sites in children were significantly smaller (P > 0.001) than those from subcutaneous sites in the same individual. Cells from different subcutaneous sites were of similar size.3. The fatty acid composition of the lipids was similar in tissue taken from the abdominal wall and from deep sites.4. The fatty acid composition of adipose tissue from the lower leg showed an increase in the monounsaturated fatty acids and a decrease in the saturated fatty acids compared with the fatty acid composition of tissue from other subcutaneous sites.
Arsanilic acid, sodium salicylate and bromide salts as potential growth stimulants for pigs receiving diets with and without copper sulphate
Authors: Barber R. S , Braude R , Mitchell K. G 
Published: June 2005

1. Results are presented of three experiments involving 112 individually fed pigs, covering the growing period between 20 and 90 kg live weight, in which the potential performance-stimulating properties of three different compounds were studied in relation to those of a dietary supplement of 250 mg Cu/kg diet.2. The three compounds studied and the levels of supplementation used (mg/kg diet) were: Expt I arsanilic acid (100), Expt 2 sodium salicylate (200), Expt 3 a mixture of bromide salts (200); each was added to the diets either alone or with 250mg Cu/kg diet given as CuSO4, 5H2O.3. The diets were given wet, ‘to appetite’ twice daily up to a daily maximum of 3 kg feed/pig. Measurements of length and of back-fat thickness at a number of points were made on all carcasses at slaughter.4. Arsanilic acid and sodium salicylate alone gave growth responses similar to those obtained with Cu alone, whereas the bromide salt had no effect on performance. None of the three compounds when added to diets in conjunction with 250mg Cu/kg diet gave results superior to those obtained with the Cu supplement alone.5. When added to the diets alone, none of the three compounds tested nor Cu had any marked effect on any of the carcass measurements.6. Arsanilic acid reduced total liver weight and markedly reduced the large increase in total liver Cu stores that resulted from supplementation of the diets with 250 mg Cu/kg diet.
Effects of calorie and protein deficiencies early in life on the subsequent learning ability of rats
Authors: Baird Angela , Widdowson Elsie M. , Cowley J. J 
Published: June 2005

1. The effect of malnutrition early in life on the subsequent learning ability of male rats was studied when they were malnourished and after they had been rehabilitated. The HebbWilliams Test of animal intelligence was used.2. Animals were malnourished from weaning, from birth, or from conception.3. The rats used for tests were fed on a (1) low-protein, (2) low-calorie, or (3) stock diet.4. The mean number of errors made by all groups of malnourished animals, tested when they were 13 weeks old, was always greater than that made by the corresponding controls. The same was true after rehabilitation for 5 weeks.
Rates of production of methane in the rumen and large intestine of sheep
Authors: Murray R. M. , Bryant A. M. , Leng R. A. 
Published: June 2005

1. An isotope tracer method for estimating methane production in sheep is described.2. The technique was used to estimate methane produced in both the upper and lower digestive tract and to determine the routes by which it was excreted.3. Four Merino ewes given lucerne chaff (33 g every hour) were used.4. Total methane production rate was 21±1.1 (se) ml/min; production in the rumen accounted for 87±1.2% of the total production; 95±1.4% of the methane produced in the rumen was excreted by eructation.5. Of the methane produced in the lower digestive tract, 89±2.3% was excreted through the lungs and 11% through the anus.
Diets and living conditions of Asian boys in Coventry with and without signs of rickets
Authors: O'Hara-May Jane , Widdowson Elsie M. 
Published: June 2005

1. The diets and living conditions of nine Asian boys with biochemical, and in most instances also radiological, signs of rickets were compared with those of nine other boys who appeared to be normal. The groups were matched according to age, religion, place of father's origin and boy's own place of birth.2. There were no outstanding differences between the diets of the boys with, and of those without signs of rickets. All had adequate to high calcium intakes. Most of the boys had low intakes of vitamin D, and those with signs of rickets generally had lower intakes than the normal boys. The food tables used for making the calculations of vitamin D intakes report the amount of the vitamin in the lipid fraction of milk. If it proves to be true that most of the vitamin D activity of milk is in the aqueous fraction, the boys would have been getting considerably more vitamin D than the results suggested, and their average intake may have been about 3.5 μg/d.3. It was not possible to make any quantitative measure of the exposure of the boys to sunlight. All Asian boys studied appeared to have their bodies more completely covered than British or West Indian boys.4. The problem of why nine boys had signs of rickets and nine had none has not been solved. It is suggested that those with signs of rickets may have had higher requirements for vitamin D than the others. When the intake of vitamin D is low and exposure to sunlight is minimal, those with high requirements will be the ones to develop signs of rickets.
The site of magnesium absorption from the ruminant stomach
Authors: Tomas F. M. , Potter B. J. 
Published: June 2005

1. A low-magnesium diet was fed to four sheep, each of which had been surgically prepared with a rumen fistula, a tube into the cranial one-third of the omasum, a tube to the cranial one-third of the abomasum and a re-entrant duodenal cannula. Mg, as gluconate or acetate, was continuously infused for 12–14 d in turn into (1) the caudal duodenal cannuia, (2) the abo-masum, (3) the omasum, (4) the rumen. A continuous infusion of the chromium-ethylene- diaminetetraacetic acid complex (CrEDTA) was maintained to the rumen. The abomasal effluent which flowed through the cranial duodenal cannula was continually sampled and the flow of Mg calculated from the concentrations of Mg and CrEDTA. Blood and rumen fluid samples were taken and urine and faeces collected during each period of Mg infusion.2. The Mg infused to either the abomasum or omasum was completely recovered at the duodenum, indicating a lack of net absorption of Mg from these stomach compartments. In contrast, 13.7–18.7 mmol (36–61 %) of the Mg infused to the rumen was not recovered at the duodenum which suggested that a substantial net absorption of the infused Mg occurred from the reticulo-rumen. Absorption of Mg caudal to the pylorus was not related to the site of Mg infusion and averaged 3.28 ±0.56 (sem) mmol/d.3. Compared with the intraruminal infusion, the post-ruminal infusion of Mg was associated with decreased plasma and rumen fluid Mg concentrations, decreased urinary Mg excretion, decreased Mg balance and increased faecal Mg excretion.4. It is concluded that no significant absorption of Mg occurs from either the omasum or abomasum in sheep and that the reticulo-rumen is the principal site of Mg absorption before the pylorus. Absorption of Mg post-ruminally is insufficient to maintain normal Mg status in the animal.
Effect of feeding a carbohydrate-free diet on the growth and metabolism of preruminant kids
Authors: Tanabe S. , Kameoka K. 
Published: June 2005

1. Experiments were done using 8-d-old kids to determine the metabolic effect of feeding a carbohydrate-free diet, and the effects of supplementation of this diet with a small amount of glycerol, sodium propionate or glucose.2. The experimental (carbohydrate-deficient) diets permitted growth nearly equal to that with the control diet (cow's milk). The kids given the experimental diets generally had lower levels of blood glucose than those given the control diet.3. With all experimental diets there were increases in the concentrations of plasma lipid and total liver lipid and a decrease in the concentration of liver glycogen; supplementation of the carbohydrate-free diet with glycerol, sodium propionate or glucose had no additional effect on these values.4. The ingestion of cow's milk produced hyperglycaemia 2 h after feeding, while in kids given the carbohydrate-free diet there was no increase in blood glucose level. The concentration of plasma free fatty acids in the kids given the carbohydrate-free diet was higher than that in control animals 24 h after feeding, suggesting that the kids given the experimental diet preferentially utilize free fatty acids as an energy source.
Gastric secretion and fermentation in the suckling pig
Authors: Cranwell P. D. , Noakes D. E. , Hill K. J. 
Published: June 2005

1. The contribution to acidification of the stomach contents of pigs by hydrochloric acid secretion or by lactic acid produced by fermentation was studied in fifteen suckling pigs from six litters born and reared either in a ‘conventional’ environment or in an isolated ‘clean’ environment. Sequential samples of stomach contents obtained during periods of up to 24 h were analysed for their chloride and lactic acid contents, pH and total titratable acidity. These values gave a measure of organic and inorganic acids respectively.2. Six pigs from two litters born and reared in a ‘clean’ environment had acid secretion in the stomach at 2 d of age, and the concentrations of lactic acid in stomach contents remained low (0-40 mmol/1) throughout the suckling period.3. Eight pigs from three litters born and reared in a ‘conventional’ environment, and a ninth pig born in this environment but moved to the ‘clean’ environment at 24 h of age, had lactic acid in concentrations of up to 250 mmol/l in stomach contents within the 1st week of life. The pattern of lactic acid production (and hence the acidity of stomach contents) was governed by the frequency of suckling.4. Both between- and within-litter variation in the age of onset of HCl secretion was evident in the group reared in a ‘conventional’ environment, and when HCl secretion did occur it was usually accompanied by a reduction in lactic acid production.5. It is concluded: (I) that the environment at birth is important in determining the fermentative ability of the stomach flora; (2) that if lactic acid is produced in large amounts in the stomach, it may partly or completely inhibit acidification by HCl.
Amino acid metabolism in the piglet: influence of level of protein and of methionine in the diet on tissue uptake and in vivo oxidation
Authors: Newport M. J. , Chavez E. R. , Horney F. D. , Bayley H. S. 
Published: June 2005

1. 14C-labelled lysine, glutamic acid and methionine were each administered as single infusions through catheters in the jugular veins of pigs between 28 and 42 d old, receiving either a low-protein (LP) (140 g protein/kg), or a high-protein (HP) (200 g protein/kg) diet. The pigs received 40 g diet/kg body-weight per d.2. l-[U-14C]lysine and l-[U-14C]glutamic acid were both rapidly removed from the plasma; 3 min after completion of the infusion less than 10% of the activity from the [14C]-lysine, and between 10 and 20 % of the activity from the [14C]glutamic acid remained in the plasma.3. In pigs killed 15 min after infusion of either [14C]lysine or [14C]glutamic acid 26% of the activity from the dose of lysine was in the liver of those receiving the LP diet, whereas the corresponding value was only 16% for those which had received the HP diet. The uptake of activity from [14C]glutamic acid by the liver was unaffected by the level of protein in the diet. More activity from [14C]lysine than from [14C]glutamic acid was recovered in the spleen, heart and brain.4. The recovery of the activity from [14C]lysine as 14CO2 in the 6 h after the infusion of the dose was lower for the pigs on the LP diet (2.7 %) than for those on the HP diet (4.8%). The corresponding values for [14C]glutamic acid infusion were 34 and 52% respectively.5. Supplementing the LP diet with five successive increments of 1.5 g DL-methionine/kg resulted in an increase from 8 to 17% dose in the recovery of activity as 14CO2 from a dose of l-[I-14C]methionine, whereas with the same supplementation of the HP diet the recovery increased from 8 to 24 % dose.
Studies on the appearance of a hepatic copper-binding protein in normal and zinc-deficient rats
Authors: Bremner I. , Davies N. T. 
Published: June 2005

1. A study has been made by gel-filtration techniques of the soluble copper- and zinc-binding proteins in rat liver after both intraperitoneal injection of Cu and dietary Cu supplementation.2. Liver Cu and Zn concentrations increased after injection of Cu, both metals accumulating in the cytosol, mainly in a fraction with an apparent molecular weight of (about 12 000)3. When Zn-deficient rats were injected with Cu, there was little change in liver Zn concentration and the occurrence of Cu in the low-molecular-weight form (about 12 000) was more transient. At most periods after injection, Cu accumulated mainly in a fraction with a molecular weight greater than 65 000.4. When the rats were Cu-loaded by dietary supplementation, virtually no Cu or Zn was found in the low-molecular-weight form in Zn-deficient rats, although they were found in the Zn-supplemented animals.5. The results suggest that Zn is essential for the accumulation of Cu in this form, but not for Cu to stimulate production of the metal-binding protein by a process requiring active protein synthesis.
Comparative effects of fructose and glucose on the lipid and carbohydrate metabolism of perfused rat liver
Authors: Topping D. L. , Mayes P. A. 
Published: June 2005

1. Livers from rats fed on a standard diet were perfused with whole blood, and infused continuously with glucose and fructose at equimolar rates.2. Infusion of fructose increased both the secretion of very-low-density-lipoprotein (VLDL)-triglycerides and the incorporation of free fatty acids (FFA) from the perfusate into VLDL-lipids, but neither of these two processes was affected by infusion of glucose.3. Infusion of fructose decreased the oxidation and increased the esterification of FFA, but glucose infusion had no effect on these processes. When fructose and glucose were infused together there was a further decrease in oxidation.4. When fructose was infused alone or together with glucose, blood concentrations rapidly became stabilized at those found in the hepatic portal vein in vivo, with similar rates of hepatic uptake to those found in the intact animal. Infusion of glucose alone resulted in continuously increasing perfusate glucose concentrations, and rates of uptake which were only 20 % of those for fructose. Blood glucose concentrations were reduced, and lactate concentrations were increased by fructose infusion, and when glucose and fructose were infused together there was a greatly increased rate of glucose uptake.5. Liver glycogen was not affected by the infusion of fructose or glucose alone; however, their combined addition significantly increased its concentration.6. Uptake of perfusate FFA was not affected by either fructose or glucose infusions.7. The results are discussed in terms of the differences in nutrition and metabolism between glucose and fructose, with particular reference to the development of hyper- triglyceridaemia.
Milk-substitute diet composition and abomasal secretion in the calf
Authors: Williams V. J. , Roy J. H. B. , Gillies Catherine M. 
Published: June 2005

1. The effect of different protein sources in milk-substitute diets on abomasal acidity and proteolytic activity was studied in Friesian calves, aged 20–58 d (Expt 1). The diets contained ‘mildly’ preheated, spray-dried skim-milk powder (MHM), ‘severely’ preheated, spray-dried skim-milk powder (SHM), fish-protein concentrate (FPC) or solvent-extracted soya-bean flour (SF) as the main protein source.2. Gastric juice was collected from abomasal pouches before feeding and at 15 min intervals for 8 h after the morning feed. Samples of digesta were obtained from the abomasum at 1 h intervals during the same period.3. Digesta pH was lower and titratable acidity higher 0-3 h after giving the diet containing MHM than when any of the other three diets was given.4. Acid secretion from the pouches for the different diets was in the order: FPC > MHM > SHM ≥ SF.5. Protease secretion from the pouches, assayed at pH 2.1, was in the order: MHM > SHM = FPC > SF.6. The effect of dry matter (dm) intake and concentration on abomasal acidity was also studied in calves given diets which contained MHM (Expt 2). This diet was reconstituted at either 100 or 149 gdm/kg liquid diet and fed at either 32.5 or 49.0 g DM/kg live weight0.75per d. Samples of abomasal digesta were collected as in Expt 1.7. A high intake ofdmat a lowdmconcentration resulted in low acidity of the digesta in the first 3 h after feeding, which suggested a dilution effect. Comparison of two diets of differentdmconcentration, which were fed in the same volume of liquid, indicated that the greater thedmintake, the greater was the amount of acid secreted.8. It is concluded that the protein sources varied in their ability to stimulate abomasal acid and protease secretion and it is suggested that this may relate to calf performance.