bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of nutrition and androgens on the composition of bovine blood plasma and seminal plasma at puberty
Authors: Baronos S. , Mann T. , Rowson L. E. A. , Skinner J. D. 
Published: May 2005

1. Experiments on three pairs of male identical twin calves have shown that underfeeding at 2.5–6 months of age, i.e. during the critical stage of sexual maturation, considerably delayed the process of puberty, as regards testicular androgen production as well as secretion of fructose and citric acid by the seminal vesicles.2. There was no marked difference in the blood-plasma content of non-protein nitrogen, vitamin A and carotene at 6 months, as between twins on a normal (N) and low (L) plane of nutrition, although the L-twins were growing and maturing more slowly. However, the blood-plasma content of glucose and of most of the free amino acids, was slightly reduced as a result of underfeeding.3. When at the age of 6 months two twin-pairs were castrated and injected with either testosterone or androstenedione (50 mg every 3rd day, for 2 months), the L-twins of both pairs and the N-twin of one pair grew at a faster rate. Moreover, the concentration of nitrogen in blood plasma increased, the rise being particularly evident in the content of indispensable amino acids. This effect, however, was more pronounced in the N- than in the L-twins.4. Testosterone treatment enhanced libido in the N-twin but not in the corresponding L-twin. Androstenedione had no effect on libido in either the N-twin or the L-twin. Thus, although testosterone and androstenedione both effectively promoted growth and nitrogen metabolism, androstenedione, unlike testosterone, was devoid of androgenic activity.
Vitamin E and hepatotoxic agents
Authors: Green J. , Bunyan J. , Cawthorne M. A. , Diplock A. T. 
Published: May 2005

1. It has been suggested that carbon tetrachloride damages rat liver by accelerating processes of lipid peroxidation at subcellular sites and that the protective action of vitamin E is due to its functioning as an antioxidant in vivo. Direct evidence for these mechanisms in vivo has been sought and is critically examined.2. The increased production of malondialdehyde by rat liver microsomal fractions during incubation with CCl4 was shown to be a function of the vitamin E status of the rat and of an in vitro reaction, which could not be correlated with the hepatotoxic action of CCI4.3. Evidence for the production of lipid peroxides by CCl4 in the livers of vitamin E-deficient and vitamin E-supplemented rats was sought (I) by measurement of ultraviolet spectral changes ('diene' formation) and (2) by direct micro-iodimetric determination of the peroxide. No differences in peroxide content were found between CC14-treated and control rats, nor were the spectrophotometric changes in the ultraviolet region related to the presence of vitamin E.4. The effect of CCI4 (2.0 ml/kg orally) on ATP levels in rat liver was studied at intervals from 3 to 68 h. The primary lesion leading to necrosis and fat accumulation after CCl4 treatment occurred many hours before the eventual slight decline in ATP. Although the levels of ATP were somewhat higher in vitamin E-deficient rats, vitamin E did not prevent the slight decline in ATP that took place. Since ATP is known to be highly sensitive to peroxidation, the results suggest that lipid peroxidation is not the primary event in CCl4 poisoning.5. The effect of CC14on the metabolism of [14C]D-α-tocopherol in the rat was studied. A single intraperitoneal dose of CCl4 (2.0 m/kg) did not increase the destruction of α-tocopherol in the liver or carcass after 24 h. Three smaller daily doses of CC14 (0.25 ml/kg) also did not increase α-tocopherol catabolism; on the contrary, significantly more α-tocopherol was found in the livers of rats treated with CCI4. These results suggest that CCl4 does not increase lipid peroxidation in vivo.
Studies on intestinal digestion in the sheep
Authors: Macrae J. C. , Armstrong D. G. 
Published: May 2005

1. In seven experiments sheep were given diets ranging from all-hay to all-barley, and also a diet comprising one part hay to two parts flaked maize. Each sheep was equipped with a cannula into the rumen and a re-entrant cannula in the proximal duodenum; six of the ten also had a re-entrant cannula in the terminal ileum. Paper impregnated with chromic oxide (Cr2O3) was given twice daily by rumen fistula.2. Amounts of α-linked glucose polymer entering and leaving the small intestine and excreted in the faeces were measured. Some values for a fraction designated non-glucose reducing polymer for cellulose and for gross energy were also obtained. The amounts passing the proximal duodenum and the terminal ileum were adjusted to give 100% recovery of Cr2O3and the values were used to measure the extent of digestion in various parts of the alimentary tract.3. When rolled or whole barley was given alone or was the major feed constituent the amount of α-linked glucose polymer entering the small intestine was 6.0±0.76% of that ingested (range 2.6–8.1%). The value was significantly lower than that found for the diet of hay and flaked maize (10.4±1.3%, range 8.0–13.6 %).The α-linked glucose polymer which entered the small intestine was almost completely digested there.4. The digestibility of the non-glucose reducing polymer, which included much of the hemicelluloses present, ranged from 51 to 73% and almost all the digestible fraction (93–97%) was digested before the small intestine when hay or predominantly hay diets were given. On high-cereal diets only 71–85% of the digested fraction disappeared before the small intestine and appreciable amounts were digested in the large intestine.5. On the all-hay diet 91% of the digestible cellulose and 67% of the digestible energy were lost before the small intestine, 0 and 21% in the small intestine and 9 and 12% in the large intestine.6. Mean digestibility coefficients determined in sheep fed solely on either whole or rolled barley were: for dry matter 88.1 and 87.9%, for nitrogen 83.5 and 82.1%, for crude fibre 53.7 and 56.6% and for gross energy 87.7 and 88.0%.
The influence on serum protein concentration of the protein intake in high-carbohydrate diets
Authors: Coles Betty L. 
Published: May 2005

1. Healthy young men ate diets high in carbohydrate with a fixed protein content: (a) 18% protein with maize starch, (b) 18% protein with sucrose, (c) 9% protein with sucrose. Sucrose or starch was given at a level of 7 g/kg body-weight per day.2. The serum albumin concentration fell by 7–10% after 16 days with all three diets; the falls were statistically significant. No change in γ-globulin concentration was seen with the 18% protein diets. With the 9% protein diet there was a significant increase in this fraction. The β-globulin concentration rose significantly with the diet containing 18% protein with sucrose but there was no change in this fraction with the other diets. α1- and α2-globulins rose significantly with the diet containing 18% protein with sucrose but no increase in these fractions was seen on the other diets.3. Possible mechanisms concerned in the production of these changes are discussed.
Effect of diet and rumen development on the composition of adipose tissue triglycerides of the calf
Authors: Garton G. A. , Duncan W. R. H. 
Published: May 2005

1. Samples of subcutaneous (inguinal) and perinephric adipose tissue were obtained, at slaughter, from each of twenty male calves. Three were neonatal animals, three were 3 days old and two were fed on reconstituted milk to appetite until they weighed 100 kg. The other twelve calves were given milk until they reached 50 kg live weight; concentrates were then included in the diet until, at 60 kg live weight, six calves were slaughtered. The remaining six calves were raised to 100 kg on concentrates alone. The weight of the empty reticulo-rumen of each slaughtered calf was recorded.2. The component fatty acids of the adipose tissue triglycerides of the neonatal and 3-day-old calves were very similar; about 80% consisted of oleic acid (18:1) and palmitic acid (16:0) and the remainder comprised stearic acid (18:0), palmitoleic acid (16:1) and myristic acid (14:0), together with very small amounts of other acids which, in the glycerides of the 3-day-old calves, included some evidently of colostral origin. The perinephric glycerides of both these groups of calves were somewhat more unsaturated than were those of subcutaneous adipose tissue.3. The continued consumption of milk by the calves slaughtered at 60 kg live weight was reflected in the presence of enhanced proportions of 14:0, 18:2, 17:0 and 17:1 in the depot triglycerides and, in addition, very small amounts of branched-chain acids andtrans18:1 were detected. A similar fatty acid pattern was observed in the triglycerides of the calves which were given milk only until they were 100 kg live weight. In all these calves only limited growth of the rumen took place.4. By contrast, the calves which were raised on solid feed from 60 kg to 100 kg and in which rumen development had taken place had depot triglycerides whose fatty acid composition resembled that found in adult animals. Increased proportions of stearic acid accompanied by relatively large amounts oftrans18:1 were present, evidently as a result of the assimilation of the products of bacterial modification of dietary fatty acids in the rumen.5. Regardless of the age of the calves and the over-all fatty acid composition of their tissue triglycerides, the intramolecular disposition of the fatty acids was similar in that saturated components were present esterified mainly in positions 1 and 3, and unsaturated acids for the most part in position 2; the only major exception to this distribution pattern was in respect oftrans18:1 which, when present, was preferentially esterified to the primary alcoholic groups of the glycerol moiety as if it were a saturated acid.
Chemical composition of organs of children who died from malnutrition
Authors: Alleyne G. A. O. , Halliday D. , Waterlow J. C. , Nichols B. L. 
Published: May 2005

1. Chemical analysis was carried out on samples of brain, liver, skeletal muscle, heart and kidney obtained from children who died of malnutrition. Total body potassium was measured before autopsy by the ‘whole body counting’ technique.2. There was a marked increase in liver fat, and the brain contributed a higher percentage of the body-weight in the more severely malnourished children.3. All the organs had approximately the same concentrations of non-collagen nitrogen. The proportion of collagen was highest in muscle.4. All organs were depleted of potassium, but the muscle was most severely affected. Brain potassium as a percentage of total body potassium was higher than normal in the most severely potassium depleted children.5. Measurements of tissue magnesium showed that there was no difference in magnesium content of tissues when expressed in terms of non-collagen nitrogen. When compared with normal values, muscle was magnesium depleted. The potassium to magnesium ratio was lowest in muscle.
The uptake and metabolism of retinol, retinoic acid and methyl retinoate by the early chick embryo
Authors: Morgan B. , Thompson J. N. , Pitt G. A. J. 
Published: May 2005

1. Fertile eggs deficient in vitamin A were obtained by feeding hens a diet deficient in retinol (vitamin A alcohol) but containing methyl retinoate.2. Radioactive retinol was injected into the albumen of three of these eggs at a level of 2 μg [6,7-14C]retinol/egg. After 5 days' incubation, 4.6–8.3% of the injected material was recovered in the lipid of the embryo, representing a four- to nine-fold concentration into the embryo from the albumen. Approximately 40–50% of this was unchanged retinol, 15–20% retin-aldehyde and 20–30% probably a long-chain fatty acid retinyl ester. The early embryo can, therefore, metabolize vitamin A very effectively.3. [6,7-14C]Retinoic acid (2 μg) was injected into normal fertile eggs, killing most of the embryos. The eggs with dead embryos were analysed; 0.24% and 0.33% of the injected material was recovered from the embryos. Two embryos which developed contained 0.51% and 0.53% of the injected dose. In no instance was any material identified other than retinoic acid. The extremely low amounts of retinoic acid absorbed by the embryos emphasize the very high toxicity of retinoic acid to the early chick embryo.4. [6,7-14C]Methyl retinoate (0.5 μg) was injected into each of four normal eggs; 8.5–11.6% was isolated as unchanged methyl retinoate after 5 days; no other radioactive substance was detected.
Physical activity, body fat and experimental cardiac necrosis
Authors: Pařézkov´ Jana , Faltov´ Eva 
Published: May 2005

1. The effects of varying levels of physical activity were tested in rats, starting at ages of 21, 32 and 55 days and continuing until go, 100, 125 and 205 days.2. Weight changes did not differ significantly between the exercise groups, except in the groups tested up to 205 days, when both the exercised group and the group with limited activity were significantly lighter than the control group.3. The weight of the soleus muscle was significantly greater in the exercised rats compared with controls and rats with limited activity, except in the oldest age-group. The weight of the tibialis anticus muscle did not differ significantly between the different exercise regimes.4. Heart weight was not significantly affected by the exercise regime, except that in rats studied from 55 to 125 days; the group with limited activity had significantly lighter hearts than those in the control group or the exercised group.5. The percentage body fat was lower in the exercised group compared with the limited activity group, and was less than the control group in both the rats studied up to 205 days and those studied from 21 to 90 days.6. Isoprenaline produced less cardiac damage in the exercised rats than in controls or in rats with limited activity. Animals who died following injection of isoprenaline had a higher percentage body fat than those animals with minimal cardiac damage.
Metabolites of riboflavine in milk, urine and tissues of animals in relation to alimentary symbiotic bacteria
Authors: Owen E. C. , West D. W. 
Published: May 2005

1. Riboflavine given orally to sheep, calves, goats and ruminating kids gave rise, in milk and urine, to extra riboflavine accompanied by hydroxyethylflavine, by formylmethylflavine and by other as yet unidentified metabolites, but subcutaneous injection of riboflavine caused prolonged excretion of riboflavine in urine and milk unaccompanied by metabolites.2. Placement of riboflavine by means of fistulas into the rumen, the abomasum or the caecum and abstraction of samples from the rumen or caecum showed that the rumen was the site of origin of the metabolites, thus accounting for the lapse of time of several hours between the ingestion of riboflavine and the appearance of hydroxyethylflavine in the urine and the absence of metabolites after subcutaneous injection of riboflavine.3. Kids in which rumination had not yet become established could not produce metabolites from ingested riboflavine although, when fed milk containing the metabolites, they readily excreted them in their urine.5. Incubation in vitro of kidney or liver tissue from cattle or goats with riboflavine did not give rise to metabolites, but these tissues could both reduce formylmethylflavine to hydroxyethylflavine in vitro.6. Post-mortem examination of animals to which riboflavine had been fed showed the presence of metabolites only in gut contents, in the urinary bladder and in the bile. When injected, riboflavine reached the bile but no metabolites were produced.7. Metabolites were found to occur naturally in the urine of ruminants in small amounts. Hydroxyethylflavine was readily demonstrable in the urine of the rabbit, but in the urine of the dog metabolites could not be found.8. From these and earlier and later experiments the conclusion is drawn that riboflavine metabolites arise in the ruminant from the degradation of riboflavine by rumen bacteria.
Studies on magnesium in ruminant nutrition
Authors: Field A. C. 
Published: May 2005

1. The excretion of magnesium in urine, milk and faeces and of faecal dry matter (DM) by grazing monozygotic twin cows has been determined at intervals throughout four grazing seasons.2. In Expt 1 three sets of twins were used to study the within-pair variance in the excretion of Mg and faecal DM. It was found that the variation within pairs was non-significant and small, less than 5% of the overall mean for all but one of the measurements made. The variation in urinary excretion of Mg within pairs was significant (P <0.05) in 1962.3. In Expt 2 the effects of lactation on the excretion of Mg and faecal DM were studied. Only one of each of the monozygotic twins was in milk at a time, each twin being in milk for one season.4. There were no significant differences in faecal nitrogen within and between pairs. On average, lactation increased faecal DM by 30% in 1964 and 24% in 1965.5. The effect of lactation on urinary Mg was not consistent. For faecal Mg the effect of lactation was a simple reflection of the increased faecal DM since lactation had no effect on the concentration of Mg in the faeces. There was no correlation between the Mg excretion in urine and milk, either singly or together, with faecal Mg excretion.6. The concentration of Mg in milk differed between twins and increased with length of lactation.7. Mean intakes of Mg by the cows have been calculated from the values for the intake of DM and the Mg content of cut herbage and compared with total excretion of Mg in urine, milk and faeces. There was a significant correlation (P <0.05) between the sets of values but estimated intakes were lower (P <0.05) than excretions. The differences between intake and excretion differed between periods (P <0.001), being greatest between July and September. Selective grazing was considered to be the main factor responsible for these differences.
Relationship between body collagen and urinary hydroxyproline excretion in young rats fed on a low-protein or low-calorie diet
Authors: Anasuya A. , Narasinga Rao B. S. 
Published: May 2005

1. Hydroxyproline was determined in urine, carcass, and skin of young rats fed on low-protein and low-calorie diets.2. Protein and calorie deprivation in young rats resulted in a marked fall in the soluble as well as insoluble collagen content of the skin.3. The collagen content of the carcass (excluding skin) was slightly greater in the deficient rats than in the weanling rats, but very much lower than in the well-fed rats.4. In rats subjected to protein and calorie deficiency, urinary hydroxyproline was markedly reduced. In these rats, most of the reduction in urinary hydroxyproline was observed within 1 week of feeding the deficient diet. Protein deficiency had affected urinary excretion of hydroxyproline more severely than calorie deficiency.5. The reduction of urinary hydroxyproline in the deficient animals can be attributed to decreased turnover rate of their body collagen. This apparent decrease in turnover rate is explained as being due to an increase in the proportion of collagen of slow turnover in these animals.6. Protein and calorie deficiency had also resulted in the depletion of non-collagen nitrogen of both carcass and skin.
The milk of the African elephant
Authors: McCullagh K. G. , Widdowson Elsie M. 
Published: May 2005

1. Analyses have been made of milk collected from thirty wild African elephants immediately after they were shot.2. The milk contained an average of 5.1% protein, 9.3% fat and 3.6% lactose. The concentration of lactose decreased and the concentration of protein and fat increased with advancing lactation. Inorganic constituents were present in approximately the same proportions as in bovine milk.3. The contribution of capric acid to the total fatty acids, previously shown to be extremely high, increased with advancing lactation.4. The significance of these findings to the preparation of a milk for rearing young elephants by hand is discussed.
The chemical composition of rumen bacteria and cell walls from rumen bacteria
Authors: Hoogenraad N. J. , Hird F. J. R. 
Published: May 2005

1. Rumen bacteria were prepared in bulk from freshly killed sheep. They were exposed to ultrasonic disintegration and a preparation of cell walls was made by differential centrifugation.2. The amino acid composition of acid hydrolysates of whole cells and cell walls was determined. Summation of these results shows that whole cells contained approximately 40% amino acids and cell walls approximately 30%.3. A considerable proportion of the alanine content of cell walls was present as the D-isomer, partly ester linked as in teichoic acids and partly more tightly bound in ‘peptide linkage’ being released only after hydrolysis in constant boiling hydrochloric acid.4. Cell walls were found to possess an alanine racemase which was inactivated only after incubation of the cell walls in 0.1 M-NaOH.5. Whole cells contained approximately 8% carbohydrates and cell walls approximately 5%. The glucose and galactose contents of whole cells and cell walls were low, accounting for little more than 2% of the dry weight of the bacterial samples.6. The amino sugar content of bacterial samples was approximately 3% and consisted mainly of glucosamine.7. The total lipid content of rumen bacteria was approximately 25% and that of cell walls varied considerably between 10 and 23%.
Growth retardation in a New Guinea boarding school and its response to supplementary feeding
Authors: Malcolm L. A. 
Published: May 2005

1. Children attending a boarding school in the New Guinea highlands, and receiving a protein-deficient diet of sweet potato and taro showed, when compared with village children, a progressive retardation of growth which was related to the number of years at school.2. Feeding of supplementary protein resulted in a dramatic acceleration of growth in both height and weight, whereas the feeding of extra calories produced an increase in only weight and skinfold thickness.3. This response to protein feeding appears to be greater than previously reported in the literature.
Mechanisms of heat damage in proteins
Authors: Bjarnason J. , Carpenter K. J. 
Published: May 2005

1. Bovine plasma albumin (BPA) containing approximately 14% moisture, when heated for 27 h at 115° suffered an appreciable loss of cystine and a small loss of lysine; at 145° all the amino acids except glutamic acid and those with paraffin side-chains, showed considerable losses. Isoleucine also showed some loss through racemization to alloisoleucine.2. BPA heated at 115° evolved H2S; at 145° other sulphur compounds were released as well, all coming from the breakdown of cystine. Possible mechanisms for this are discussed.3. Ammonia was also liberated from BPA heated at 115°. The degree of correlation of lysine binding in different proteins with ammonia liberation and amide changes has led us to suggest that the main reaction of ε-amino lysine groups is with amide groups of asparagine and glutamine. Reaction of ε-amino groups with carboxylic groups is thought to be less important.4. Model experiments have shown that a reaction between amide groups and the e-amino group of lysine in proteins can occur at practical drying temperatures.5. Reactions of the ε-amino group of lysine with destruction products of cystine is also considered to be partially responsible for the lysine binding in heated proteins.