bluuebunny/crossref_metadata_2025 huggingface dataset:
The analysis of α-tocopherol and ubiquinone in rat liver
Authors: Diplock A. T. , Green J. , Bunyan J. , McHale D.
Published: June 2005

1. A comparative study has been made of five methods of saponifying normal and vitamin E-deficient rat liver and subsequently measuring ubiquinone and α-tocopherol. 2. Losses of ubiquinone and α-tocopherol occur under certain conditions, and three of the methods were judged to be unsatisfactory. Recoveries of α-tocopherol are nearly quantitative under the conditions of ToŠić & Moore (1945), but methods that use large reaction times or weaker alkali destroy tocopherol, and over 50 % loss can be encountered. Ubiquinone does not seem as sensitive to the time of reaction, but is sensitive to the concentration of alkali and amount of water present during saponification.
Pancreatic amylase in chickens fed on soya-bean diets
Authors: Lepkovsky S. , Koike T. , Sugiura M. , Dimick M. K. , Furuta F.
Published: June 2005

1. The action of raw and heated soya beans on pancreatic function was studied by measuring the amylase activity of the pancreases and intestinal contents of intact chickens and of chickens with ileostomies at fasting and after eating, before and after adaptation to heated and raw soya-bean diets, with a methionine supplement and without. 2. The concentration of amylase in the pancreases of 8-week-old chickens eating raw soya-bean diets was lower than that of those eating heated soya-bean diets. These chickens were deficient in methionine; supplementation of the raw soya-bean diet with methionine greatly increased the levels of amylase in the pancreases of such chickens; supplementation of the heated soya-bean diet with methionine increased the levels of amylase in pancreases to a smaller extent. 3. Methionine was less effective in increasing the amylase levels of the pancreases of 11-week-old chickens eating raw soya-bean diets, since at this age the deficiency of methionine was much less pronounced. 4. More amylase activity was found in intestinal contents of chickens eating raw soya-bean diets than in those eating heated soya-bean diets. 5. In vitro studies showed that fractions prepared from raw soya beans, all containing high levels of trypsin inhibitors, stabilized amylase activity despite the active proteolysis of other protein substrates in the same amylase-containing mixtures. 6. CaCl2stabilized amylase activity in vitro in unactivated and activated pancreatic juice as such, and after additions of raw soya beans or their fractions before and after autoclaving. 7. The increased levels of amylase found in the intestinal contents of the chickens eating raw soya beans may represent greater secretion of amylase activity by the pancreas, stabilization of amylase activity by the raw soya bean, or both factors. Interpretation of measurements of amylase activity in the intestinal contents of chickens eating heated or raw soya beans is uncertain. 8. The bearing of this work on current views of the nutritional value of raw and heated soya beans is discussed.
Utilization of salts of volatile fatty acids by growing sheep
Authors: Ørskov E. R. , Allen D. M.
Published: June 2005

1. The effect, on the concentration of volatile fatty acids (VFA) in the rumen, of increasing the frequency of feeding from twice daily to four or six times daily was investigated in sheep given isocaloric rations containing VFA salts. In a second experiment isocaloric rations containing acetate and propionate were given to groups of lambs in two or six equal feeds daily. The efficiency with which the lambs utilized the VFA salts was measured as gain in live weight, empty body weight and carcass weight and was compared to that of lambs receiving only the basal ration. The composition of the carcasses was estimated from that of the loin. 2. Increasing the frequency of feeding from twice daily to four or six times daily significantly reduced the marked changes in rumen VFA composition associated with giving rations containing VFA salts twice daily. In lambs receiving acetate and propionate, final live weight, empty body weight and carcass weight were significantly greater than in lambs receiving only the basal ration (P < 0.001). The combustible energy from added VFA was apparently utilized more efficiently than the calculated metabolizable energy of the basal rations given above maintenance level, and there was no difference between the utilization of acetate and propionate. 3. There were no differences approaching significance between feeding twice daily and six times daily either between groups of lambs receiving only the basal diet or between those given the diets supplemented with VFA salts. Nor were there any interactions between VFA and frequency of feeding. 4. It is postulated that in ruminants the effect of frequency of feeding depends on the environment and level of feeding.
The role of carotenoids and vitamin A in encephalomalacia
Authors: Prohászka L.
Published: June 2005

1. The relationship of vitamin A and carotenoids with encephalomalacia was examined in chick-raising farms and under laboratory conditions. 2. In encephalomalacic chicks on the farms a significant decrease in liver carotenoid content was demonstrated. In the diseased chicks the carotenoid contentwas below 0.30 mg/100 g liver, as against the normal values of 0.40–1.0 mg/ 100 g. 3. Under experimental conditions incidence of encephalomalacia could be decreased by oral treatment with the synthetic carotenoid ethyl β-apo-8'-carotenoate. This implies that deficiency in carotenoid is not merely a concomitant sign of encephalomalacia, but has also a causative role, as sufficient carotenoid reserves confer a certain protection against the disease. 4. The pathogenetic role of carotenoid metabolism in encephalomalacia was supported by certain observations. Factors inhibiting the accumulation of ethyl β-apo-8'-carotenoate in the liver predispose chicks to the disease. In chicks 4–5 weeks old in addition to those with vitamin A reserves higher than 800 i.u./g liver, the accumulation of carotenoids in the liver was about 10% of that measured in chicks more than 7 weeks old, or in those with vitamin A reserves not higher than from 100 to 200 i.u./g. In fact, encephalomalacia occurs mainly among chicks 3–5 weeks old. Also, reserves of vitamin A exceeding 800 i.u./g liver were found to predispose chickens to encephalomalacia.
Nutrient intake during lactation in Australian women
Authors: Hitchcock Nancy E. , English Ruth M.
Published: June 2005

1. The dietary intakes of forty-one mothers were investigated during lactation, between the 6th and 20th weeks after delivery. The group comprised thirty primiparae and eleven multiparae. 2. The women studied were apparently lactating satisfactorily, as the infants were judged healthy and their average weekly weight gain was 193 g (6.9 OZ). 3. The average daily intakes of nutrients by the mothers were compared to those listed inDietary Allowances for Australia.Intakes of calories, protein, calcium, iron and ascorbic acid were 514±75 (16%), 17.0±2.7 g(17%), 725±75 mg(36%), 5.2±0.43 mg (31%) and 21±5.3 mg (21%) respectively below the allowances for these nutrients. It is suggested that the allowances for calories, protein, calcium, iron and ascorbic acid may have been set at too high a level. 4. The incidence of successful breast-feeding in western countries compared with others is briefly discussed. It is concluded that diet plays a minor part and that the dominant factors are cultural and social.
Arginine in poultry nutrition
Authors: Smith G. H. , Lewis D.
Published: June 2005

1. A series of trials has been conducted to investigate interactions between amino acids in the diet of the growing chick. 2. Diets were prepared in which the level of arginine was limiting. To these diets were added excess levels of lysine, histidine, isoleucine and leucine. Of these amino acids lysine was most effective in reducing the growth rate. Growth rate was restored by adding arginine. 3. The addition of excess quantities of lysine to a diet in which the level of tryptophan was limiting and the level of arginine adequate did not reduce growth rate. 4. These results confirm the existence of a specific interaction between arginine and lysine. The concept is discussed that such specific interactions between pairs or among small groups of amino acids might underly many of the phenomenons of amino acid imbalance.
Milk in schools: an experiment in nutrition education
Authors: McKenzie J. C. , Mattinson Juliet , Yudkin John
Published: June 2005

1. An experiment was conducted with 4600 children in nine schools, in which an attempt was made to persuade a greater number of children to take school milk. The proportion taking the milk before the experiment ranged from about 25 to 65%.

2. Four methods of nutrition education were used: posters, lectures and films each in two schools, and pamphlets in one school. The remaining two schools acted as controls.

3. The material was used for one term in all seven ‘experimental’ schools, and again for the following term in one of the schools receiving each of the different forms of education.

4. Although it appears that there was a small increase in the number of children that said they would take milk, there was no significant increase in the number that did in fact do so, in either the first or the first or the second term.

5. The analysis of the possible causes for this failure to increase milk consumption suggests that nutrition education does not affect dietary behaviour if the factors that limit consumption are sufficiently strong.
Studies on magnesium in ruminant nutrition
Authors: Suttle N. F. , Field A. C.
Published: June 2005

1. In expt 1 daily supplements of 0 or 27–28 g potassium, with 0 or 7·5 1. water, were given to each of eight fistulated wether sheep on a hay and concentrate diet in two 4 × 4 latin square experiments. Faeces were collected for the last 4 days of, and urine throughout, 10-day treatment periods.

2. Adding K to the diet decreased the urinary output of magnesium by 33% (P< 0·001) and significantly increased those of phosphorus, sodium and calcium by 98, 76 and 150%, respectively. Faecal outputs of Mg and K were increased, whereas that of P was decreased. The retentions of P and Na tended to be decreased, whereas that of K was increased (P< 0·001). Mg in serum was decreased by 0·4 mg/100 ml (P< 0·05) and K increased by 4·9 mg/100 ml (P< 0·001).

3. Increasing the water intake increased the urinary outputs of Mg, P, Na and Ca by 33, 165, 47 and 200%. The faecal output of Ca was increased and the retentions of Mg, P and Ca were decreased (P< 0·01).

4. The effects of water and K were generally independent, but interactions affected the urinary outputs of P and K and the retention of K.

5. The increases in urinary Na output were three- and eight-fold greater during the first 3 days of increased water and K intakes than during the balance study.

6. In expt 2, mineral balance studies were conducted before and after supplementing the diet with potassium acetate, using five wethers from Expt 1. K intakes were similar to those of Expt 1. The effects of potassium acetate and KCl were generally similar qualitatively but the acetate produced greater decreases in urinary Mg and faecal P outputs and greater increases in urinary Na and K outputs than KCl. K in serum was increased by 28 mg/100 ml but Mg was not affected.

7. The nature of these responses in discussed with particular reference to the aetiology of hypomagnesaemic tetany.
Vitamin E and stress
Authors: Green J. , Muthy I. R. , Diplock A. T. , Bunyan J. , Cawthorne M. A. , Murrell Elspeth A.
Published: June 2005

1. The nature of the relationship between vitamins A and E has been studied in the rat and the chick.

2. Stress induced by diets rich in polyunsaturated fatty acids (PUFA) was found to have no effect on the liver vitamin A reserves of vitamin E-deficient rats given dietary vitamin A or repeated small oral doses of vitamin A.

3. Dietary PUFA did not affect the liver vitamin A reserves of young rats given necrogenic diets deficient in vitamin E and selenium, nor were these reserves affected by the onset of liver necrosis or its prevention by Se.

4. The effect of dietary PUFA on the rate of depletion of liver vitamin A reserves in weanling rats or rats depleted initially of vitamins A and E and then given a single large dose of vitamin A was studied over periods from 2 to 12½ weeks. In three experiments the dietary PUFA did not significantly accelerate vitamin A depletion. In one experiment the depletion rate was increased, but this was not reversed by dietary vitamin E and thus could not be attributed to an enhancement of peroxidation in vivo but rather to a toxic effect. The effect of vitamin E in these experiments was not consistent but, in general, it slightly decreased the rate of depletion.

5. Large doses of vitamin A did not affect the metabolism of small amounts of [14C]D-α-tocopherol in the vitamin E-deficient rat or chick, when interaction of the two vitamins in the gastro-intestinal tract was avoided.

6. Large doses of vitamin A (40000 i.u. in total) given to vitamin E-deficient chicks receiving a diet containing 1% linoleic acid (as maize oil esters) did not accelerate the onset of encephalomalacia and therefore failed to exert a pro-oxidative effect on tissue tocopherol.

7. The conclusion drawn from these experiments was that any relationship that may exist in vivo between vitamins A and E is not concerned with an effect of vitamin E in preventing oxidation of vitamin A. A critical review of the literature on the nature of the relationship in general supports this view.
Adaptive enzyme changes in liver and muscle of rats during protein depletion and refeeding
Authors: Stephen Joan M. L.
Published: June 2005

1. Young rats were kept on a 6% casein diet for 4–7 weeks and then either killed or returned to a stock diet. Control rats were given a stock diet.

2. Argininosuccinate lyase (EC 4.3.2.1, L-argininosuccinate arginine-lyase) was assayed in liver, and amino acid activating enzymes were assayed in liver and muscle of rats after depletion and while they were refed on the stock diet. Levels of enzymes were compared with those in the control rats.

3. Amino acid activating enzymes were markedly increased in liver at the end of the depletion period, but returned almost to normal levels after 4–6 days of refeeding. In muscle the enzyme levels were not decreased after depletion, but began to rise after 4 days of refeeding.

4. Argininosuccinate lyase activity in depleted female rats was about half that in control rats and rose again slowly on refeeding. Male rats were hardly affected by depletion.

5. It is suggested that these enzyme changes play a part in the adaptation of the rat to a reduced protein intake.
Volatile fatty acids in the digestive tract of the fowl
Authors: Annison E. F. , Hill K. J. , Kenworthy R.
Published: June 2005

1. Examination of the digesta from all regions of the avian digestive tract showed that volatile fatty acids (VFAs) were present in greatest concentration in the caeca and that they comprised mainly acetic, propionic and butyric acids.

2. All droppings contained VFAs but they were present in highest concentration in those of caecal origin. Caecectomy was followed by a marked reduction in the total output of VFAs.

3. Birds 14–20 weeks of age had similar concentrations of VFAs along the tract and similar numbers and distribution of micro-organisms.

4. Portal blood contained all the VFAs found in the digestive tract whilst peripheral blood contained only acetic and formic acids.

5. The almost complete absence of VFAs from the tract contents of germ-free birds showed that the VFAs normally present in the tract were of microbial origin.

6. The presence of similar levels of acetate in the peripheral blood of conventional and germfree birds indicated that circulating acetate was mainly of endogenous and not microbial origin.

7. The significance of VFAs as an energy source is discussed.
Protein-rich mixtures for human consumption based on fish flour, sunflower presscake meal, dried skim milk and wheat flour
Authors: Ballester Digna , Barja ITA , Yáñez E. , Donoso G.
Published: June 2005

1. The quality of the protein in five high-protein mixtures intended for human consumption and made from materials that are available in Chile is reported.

2. The ingredients were fish flour, bread, wheat (Triticum sativum Lam.) flour, roasted whole wheat flour, a wheat flour made from a variety of durum wheat (T. durum Desf.), skim milk and sunflower presscake, mixed in different proportions.

3. The net protein utilization when fed to rats in diets at the 10% level of protein calories gave values in the range 66–76, which compare well with that (67), found for Incaparina, an all-vegetable mixture produced by the INCAP Group and used in Colombia, and are higher than the values (55 and 56) obtained for Peruvitas, which are mixtures made up basically from cottonseed and quinoa reinforced with dried skim milk.

4. The protein values of the mixtures, expressed as net dietary protein calories %, were calculated from their biologically determined net protein utilization (operative), and gave values that ranged from 10·5 to 12·8, which are higher than the recommended values in diets for infants and toddlers.
Digestion of concentrate and of hay diets in the stomach and intestines of ruminants
Authors: Topps J. H. , Kay R. N. B. , Goodall E. D. , Whitelaw F. G. , Reid R. S.
Published: June 2005

1. Two young steers, aged approximately 6 months and each fitted with a rumen and an abomasal cannula, were used to measure the flow of digesta to the abomasum over periods of 24 h. A diet of concentrates, at two levels, and a diet of hay cubes were given to the steers. Paper impregnated with chromium sesquioxide was inserted into the rumen twice daily.

2. The amount of digesta passing to the abomasum and the output of faeces were measured and the values were adjusted to give 100% recovery of chromium sesquioxide. Measurements were also made of concentrations of plasma glucose, of volatile fatty acids (VFA) in both the rumen and abomasal fluid, and of rumen fluid volume and outflow.

3. About 60–80% of the digestible dry matter and of the digestible energy of both diets disappeared from the forestomach (reticulo-rumen and omasum). The amounts of starch flowing through the abomasum differed little between diets and ranged from 29 to 77 g daily.

4. The volume of rumen fluid did not differ consistently between diets, but the outflow of fluid from the rumen was considerably higher when hay was given.

5. Diet had little influence on plasma glucose but affected the concentrations and molar proportions of VFA in the rumen fluid, and to a lesser extent in the abomasal fluid.
The effect of tungstate ingestion on xanthine oxidase in milk and liver
Authors: Owen E. C. , Proudfoot R.
Published: June 2005

1. The ingestion of doses of up to 6 g sodium tungstate (56 mg W/kg body-weight) by goats was found to diminish the amount of xanthine oxidase secreted in their milk so that, in some samples, the enzyme became undetectable. This effect occurred whether the goats were eating a semi-synthetic or a conventional diet.

2. Tungstate ingestion by goats did not affect the concentration of riboflavine in their milk.

3. The ingestion of sodium tungstate by young goats for 3–5 months diminished the amount of xanthine oxidase in their livers.

4. When given in early lactation to two cows, doses of sodium tungstate (up to 20 g) diminished the titre of xanthine oxidase in their milk with no concomitant effect on the yields.

5. Much later in lactation the milk phosphatase of these two cows was poorly correlated with milk xanthine oxidase. Reasons for this are discussed.

6. Under anaerobic conditions, with xanthine as substrate and triphenyl-tetrazolium chloride as hydrogen acceptor, neither molybdate nor tungstate affected the xanthine oxidase activity of cow's or goat's milk in vitro. Molybdate in vitro did not enhance the very low titre of human milk.
The fate of water in the rumen
Authors: Warner A. C. I. , Stacy B. D.
Published: June 2005

1. The51Cr complex of ethylenediamine tetra-acetic acid was used as a soluble marker substance in sheep fed restricted amounts (700 g daily) of roughage diets. It was injected into the rumen at various stages of the feeding cycle and rumen volumes and flow rates were calculated.

2. The average resting rumen volume for sixteen sheep (average body-weight 39 kg) was 3.9 l.; the average resting dilution rate was 0.077 h-1so that the net inflow rate averaged 0.29 l./h; the average rate of absorption of water from the resting rumen into the blood was 0.05 l./h.

3. There were marked differences in all these values, both within sheep on different days (coefficient of variation nearly 20%) and between sheep (coefficient of variation more than 25%). The resting salivary inflow rate was also found to fluctuate considerably.

4. During feeding, the salivary inflow rate increased; there was usually both an expansion of rumen volume and an increased rate of outflow. There was no evidence of diffusion of water from the blood into the rumen.

5. Following eating, return to resting conditions was slow.

6. When the sheep drank, there was an expansion of the rumen volume and usually an increased outflow rate. The rate of absorption of water from the rumen increased slightly, but only for a short time. Occasionally after drinking it was found that rumen marker concentrations were slightly higher than expected probably because a small part of the imbibed water bypassed the rumen down the reticular groove into the omasum.

7. Most of the water drunk in a day was consumed in a few minutes. Compared with this rapid rate of drinking, the rate of absorption of water from the rumen was always a very slow process; this finding is in disagreement with recent views expressed in the literature. However, when considered over the whole day, the amount of water absorbed from the rumen may have been approximately equal to the amount of water drunk.

8. During periods of both feeding and drinking, the mean outflow rate was about 0.7 l./h in several series of experiments.

9. When sheep were held without food or water past their normal time for eating and drinking, the net inflow rate into the rumen soon started to decrease, but there was no immediate effect on rumen volume.

10. The present work reveals the potential usefulness of the soluble marker technique in defining the changing patterns of fluid movement in the rumen throughout the day.
The effect of increasing amounts of dietary red palm oil on milk fat secretion in the cow
Authors: Storry J. E. , Hall A. J. , Johnson V. W.
Published: June 2005

1. The effects, on the secretion in milk of fat and its component fatty acids, of supplementing a basal diet low in fat with red palm oil at three levels are reported.

2. The secretion of total fat and of the fatty acids contained in the oil supplement was positively correlated with the dietary intakes, except for linoleic acid which was hydrogenated in the rumen before its absorption and secretion in milk.

3. Evidence for the synthesisde novoof palmitic acid and for the possible depression of intramammaryde novosynthesis by high levels of dietary fat is discussed.
Nutrient intakes during pregnancy, lactation and after the cessation of lactation in a group of Australian women
Authors: English Ruth M. , Hitchcock Nancy E.
Published: June 2005

1. The dietary intakes of twenty-six women were investigated during their first pregnancy, at 6–8 weeks post-partum and at 6 months post-partum or after the cessation of breast-feeding.

2. Of this group, sixteen subjects were apparently breast-feeding satisfactorily at 6–8 weeks post-partum, as judged by the average weekly weight gain of their infants (202 g).

3. Changes in food consumption and nutrient intake were studied, together with changes in body-weight and activity. The subjects did not consume more calories during pregnancy. It appeared that this was a result of dietary advice received plus some curtailment of activity during pregnancy. There was an increase in intake of nutrients during lactation.

4. Intakes of iron during the third trimester of pregnancy and of ascorbic acid during lactation were 1.9 ± 0.3 mg (16%) and 26 ± 7.3 mg (26%) respectively below the allowances recommended by the (Australian) National Health and Medical Research Council. The significance of these intakes is discussed.

5. No difference was detected in the diets during pregnancy of women who breast-fed compared with those who did not.
The determination of the true digestibilities of interesterified fats in young pigs
Authors: Freeman C. P. , Holme D. W. , Annison E. F.
Published: June 2005

1. The true digestibilities of esterified lauric, palmitic, stearic and oleic acids in lard, coconut oil and soya-bean oil were determined by incorporating the [1-14C]-labelled acids into the fats by interestification. The true digestibilities of the labelled fats also were compared with the digestibilities of their unlabelled counterparts, corrected for endogenous fat by the conventional procedure.

2. The true and corrected coefficients of digestibility of each of the fats were in good agreement, but there were significant differences between the true and corrected coefficients for individual fatty acids, particularly for palmitic and stearic acids.

3. The amount of endogenous fat produced with each of the fats calculated from the values found with the labelled fatty acids was greatest when the fat supplement was lard, when a disproportionately high level of palmitic acid was excreted.

4. Evidence was obtained of the extensive hydrogenation of oleic acid in the digestive tract of the pig.
Site differences in the fatty acid composition of subcutaneous adipose tissue of obese women
Authors: Pittet Ph. G. , Halliday D. , Bateman P. E.
Published: June 2005

1. Adipose tissue samples were obtained by needle biopsy from three subcutaneous sites (thigh, abdomen and upper arm) in twenty-two obese women. The fatty acid composition was determined using gas-liquid chromatography and the results presented relate to eleven component fatty acids.

2. The fatty acid composition of adipose tissue obtained from the arm and abdomen was remarkably similar, with the exception of the levels of lauric acid.

3. The analyses showed that the majority of the saturated fatty acids were present in smaller proportions whilist the majority of unsaturated fatty acids were present in larger proportions in the thigh than in the two other sites. Highly significant inter-site differences were demonstrated for six of the major fatty acids and also for both the total amounts of saturated and unsaturated fatty acids and their ratios.

4. No marked differences in the fatty acid composition of adipose tissue from obese subjects were revealed during this study when compared with previously reported results obtained from ‘normal-weight’ subjects.
The relationship between protein turnover and energy balance in lean and genetically obese (ob/ob)mice
Authors: Miller B. G. , Otto W. R. , Grimble R. F. , York D. A. , Taylor T. G.
Published: June 2005

1. Groups of lean and genetically obese (ob/ob) mice were adapted to varying energy intakes and the rates of total protein turnover in liver, gut and kidney were measured.

2. Lean mice gained less weight when fed above maintenance and lost less weight when fed below maintenance than obese mice.

3. Hepatic protein turnover (mg/d) was sigmoidally related to digestible energy intake in lean mice but showed no significant changes with dietary intake in obese mice.

4. The changes in protein turnover resulted from changes in both the half-lives of protein synthesis and catabolism and in tissue protein content.

5. In the lean mice, protein turnover in kidney and gut was not significantly changed with increasing energy intake until the highest level was reached.

6. The findings suggest that protein turnover may be an important cycle for the regulation of energy balance in mice and that this cycle is impaired in the genetically obese (ob/ob) mice.
Relation between erythrocyte selenium concentrations and glutathione peroxidase (EC 1.11.1.9) activities of New Zealand residents and visitors to New Zealand
Authors: Rea Heather M. , Thomson Christine D. , Campbell Dianne R. , Robinson Marion F.
Published: June 2005

1. Erythrocyte, plasma and whole blood selenium concentrations and glutathione peroxidase (EC I.11. 1.9; GSHPx) activities were measured (1) in 104 healthy New Zealand residents living in Otago, a low-soil-Se area (2) in sixty-four surgical patients, including nineteen patients on total parenteral nutrition and twenty-three cancer patients (3) in fifty-two ‘overseas subjects’ (twenty-five visitors to Otago from outside New Zealand and twenty-seven Otago residents on return from overseas travel).

2. Blood Se concentrations reflected dietary Se intake; means for Otago patients, healthy subjects and overseas subjects were different (0043, 0.059, 0.136 μg Se/ml blood respectively) and mean for overseas residents was greater than for New Zealand overseas travellers.

3. Erythrocyte Se concentration was always greater than plasma Se, and plasma Se was a smaller pro- portion of erythrocyte Se for patients compared with the controls.

4. GSHPx activities were different in the three groups, and vaned directly with erythrocyte Se until a plateau was reached at approximately 0.14 μg Se/ml erythrocytes.

5. Overseas subjects showed no relationship between erythrocyte Se and GSHPx activity. This agrees with some overseas studies and the significance of this finding is discussed.

6. Plasma Se concentration remained the most sensitive index of short-term changes in Se status, and erythrocyte Se and GSHPx activities for long-term changes in New Zealand subjects. Use of these measure- ments for overseas subjects with higher blood levels is discussed.
Protein quality in cereals and pulses
Authors: Ford J. E. , Hewitt D.
Published: June 2005

1. Polyethyleneglycol (PEG 4000) was examined for its influence on relative nutritional value (RNV) and available methionine in sorghum (Sorghum ulgare Pers.), field beans (Vicia faba L.) and barley, as measured microbiologically with Streptococcus zymogenes. The results were assessed in relation to the content of tannins in the test samples.

2. In grain of hybrid sorghum the RNV averaged 87 (range 79–92) for six low-tannin varieties and 41 (30–53) for eleven high-tannin varieties. The corresponding available methionine values averaged 17.0 (15.7–18.9) and 8.9 (6.7–11.0) g/kg protein. Addition of PEG 4000 to the test samples increased the average RNV of the high-tannin varieties from 41 to 78, and the average available methionine content from 8.9 to 16.2 g/kg protein.

3. With seed of ten coloured-flowered varieties of field beans, treatment with PEG gave a small but consistent increase in the available methionine content, which resulted from the inactivation of tannins in the testa.

4. In twenty-three samples of barley grain, treatment with PEG had no effect on the values obtained for available methionine.

5. Treatment of high-tannin sorghum grain with ammonia has been reported to inactivate the tannins and increase the nutritional value for rats and chicks. This finding was confirmed. The present study showed that ammonia and PEG 4000 were equally effective in enhancing the nutritional quality as measured in the microbiological tests.
Protein quality in cereals and pulses
Authors: Ford J. E. , Hewitt D.
Published: June 2005

1. Two preceding papers in this series describe the application of microbiological and other in vitro tests in the evaluation of sorghum (Sorghum vulgarePers.), field beans (Vicia fabaL.) and barley, and in assessing the influence of polyethylene glycol (PEG 4000) on the nutritional availability of the methionine. The present paper gives for comparison the results of bioassays on some of the same test samples. Net protein utilization (NPU) in rats was measurd by the nitrogen balance method, and N digestibility in chickens by the ileal analysis procedure.

2. In rat tests on sorghum, N in grain of high-tannin varieties was poorly digested. Supplementation of the test diets with 0.1 g PEG 4000/g protein gave a large improvement, which was partly offset by an apparent decrease in biological value (BV). With chickens N digestibility was even lower, and was similarly improved with PEG 4000. Treatment of high-tannin grain with ammonia solution was also effective in improving N digestibility.

3. With low-tannin sorghum the amino acid digestibilities were uniformly high and were not affected by addition of PEG to the test diet. With high-tannin sorghums they were low and less uniform, and were much improved by PEG 4000.

4. With field beans, the influence of the seed-coat tannin on protein utilization was much less pronounced than with sorghum. In chickens there was a significant effect (P< 0.05) of PEG 4000 on N digestibility in a high-tannin variety. With rats the effect was smaller and not significant.

5. In four samples of barley, N digestibility was high (0.87–0.96) and was not further improved by PEG 4000. The BV of a high-lysine cultivar proved marginally inferior to that of a normal variety. Possible reasons for this are discussed.

6. Over all, the results were closely consistent with those from microbiological tests withStreptococcus zymogenes.
Effect of zinc deficiency on muscle fibre type frequencies in the post-weanling rat
Authors: Maltin C. A. , Duncan L. , Wilson A. B. , Hesketh J. E.
Published: June 2005

1. Male weanling rats were maintained on diets either deficient or adequate in zinc for a period of 4 weeks. The rats on the deficient diet showed a reduction in food intakesand growth.

2. After 4 weeks both soleus muscles and the lateral portion of the diaphragm were studied histochemically to examine the relative frequencies of the fibre types.

3. The soleus muscles of the deficient animals showed a significant change in the proportion of slow and fast fibres. The diaphragm muscles of the deficient animals had a significant increase in the proportion of fast-twitch oxidative glycolytic fibres and a significant decrease in fast-twitch glycolytic fibres compared with the controls.

4. Stainable lipid increased in the diaphragm muscle of the deficient animals with respect to their pair-fed controls.
Nt-methyl histidine excretion by poultry: not all species excrete Nt-methyl histidine quantitatively
Authors: Saunderson C. Linda , Leslie S.
Published: June 2005

1. The rate of elimination of administeredNτ-[14CH3]methyl histidine was used to assess the validity ofNτ-methyl histidine excretion as an index of muscle protein breakdown in poultry.

2. Broiler chicks (2–3 and 4–5 weeks old), laying hens, adult quail (Coturnix coturnix japonica), adult cockerels and turkey poults (2–4 weeks old) were tested.

3. All except the turkey poults showed quantitative recoveries ofNτ-[14CH3]methyl histidine within 1 week.

4. Turkeys showed a different pattern ofNτ-[14CH3]methyl histidine output; the mean total recovery after 14 d was less than 50% of the injected dose. The majority of the label remaining after this time was found in breast muscle.

5. All birds tested excretedNτ-methyl histidine unchanged, although a small amount sometimes appeared as another metabolite.

6. No significant oxidation ofNτ-[14CH3]methyl histidine by broiler chicks, turkey poults or adult quail was found.

7. The results show that excretion ofNτ-methyl histidine is a useful measure of muscle protein breakdown in the domestic fowl and quail but not in turkeys.
Calcium and phosphorus requirements of the ewe during pregnancy and lactation
Authors: Braithwaite G. D.
Published: June 2005

1. Mineral balance and radioisotope studies have been carried out to test the adequacy of recent Agricultural Research Council (1980) recommendations for calcium and phosphorus for pregnant and lactating ewes. At the same time, Ca metabolism was compared throughout pregnancy and lactation in ewes restricted to these recommendations and in ewes given a plentiful supply of dietary Ca and P.

2. Irrespective of their Ca intake, ewes were unable to absorb enough dietary Ca in late pregnancy and early lactation to meet the high demands, and skeletal stores of Ca were mobilized to make good the deficit.

3. Whereas ewes given the plentiful intake absorbed enough dietary Ca in mid- to late lactation to replace their lost skeletal Ca stores, ewes given the restricted Ca and P intake did not and, at the end of lactation, were still in deficit of about 10% of their total body Ca.

4. Since Ca absorption in the restricted ewes occurred at the maximum efficiency (66%) expected from a hay and concentrates diet, the Agricultural Research Council (1980) recommendations for Ca, particularly in mid-to late lactation, must be inadequate.

5. It is suggested that in calculating requirements, allowance must be made for the inevitable loss and subsequent replacement of skeletal stores.

6. The endogenous faecal loss of Ca was found to vary in direct relation to the food intake, and the significance of this finding to calculations of Ca requirements is discussed.
Calcium and phosphorus requirements of the ewe during pregnancy and lactation
Authors: Braithwaite G. D.
Published: June 2005

1. Mineral balance and radioisotope studies have been carried out to test the adequacyof the recent Agricultural Research Council (1980) recommendations for calcium and phosphorus for pregnant and lactating ewes. At the same time, P metabolism was compared throughout pregnancy and lactation in ewes fed according to these recommendations and in ewes fed a plentiful supply of dietary Ca and P.

2. Bone mineral stores were mobilized in late pregnancy and early lactation, irrespective of the rate of P absorption. These stores were then replaced in mid- to late lactation in ewes given the plentiful Ca and P intake but not in the ewes given the restricted intake.

3. Results suggest that these changes in bone stores occurred as a result of changes in Ca requirements rather than in P requirements, and that accretion of P into bone or resorption of P from bone occurred merely as a conseqence of this change in Ca requirements.Immediate demands for P for maintenance and fetal or milk production do not reflect net Pdemands, which also take into account changes in bone P metabolism.

4. The rate of P absorption was directly related to net demands and the rate of endogenous excretion was inversely related to net demands.

5. Absorption and endogenous faecal loss of P were also both directly related to P intake.

6. A lack of dietary Ca, particularly in mid- to late lactation, makes it impossible to draw conclusions on the adequacy of the Agricultural Research Council (1980) recommendations for P. Results do suggest, however, that P requirements ought to be calculated according to net demands for P rather than immediate demands.
Minerals and trace elements in total diets in The Netherlands
Authors: Dokkum W. Van , De Vos R. H. , Muys TH. , Wesstra J. A.
Published: June 2005

1. During a period of 2·5 years, every 3 months 221 different food items forming a ‘market basket’ were purchased, prepared and divided into twenty-three food-commodity groups. The ‘market basket’ was based on a study of the dietary intake of 18-year-old male, Dutch adolescents. In the (homogenized) food groups various minerals and trace elements were determined.

2. The mean daily amounts of cadmium (21 μg), mercury (0·7 μg), lead (32 μg), tin (0·65 mg), arsenic (38 μg) and bromine (8 mg) in the diet of adolescents, as calculated from the concentrations analysed in the food groups, were all (well) below the Food and Agriculture Organization/World Health Organization acceptable daily intake (ADI) value (Codex Alimentarius Commission, 1984).

3. The mean daily amounts of zinc (14 mg) and selenium (72 μg) seemed to be adequate compared with the Dutch recommendations, (Voedingsraad (Dutch Nutrition Council) 1986). The amounts of copper (mean value 1·5 mg/d) and iron (mean value 14 mg/d) in the total diet were marginal. Contents of calcium (1340 mg/d), magnesium (433 mg/d) and iodine (402 μg/d) were all well above the Dutch recommendations for male adolescents. Sodium intake, corresponding to 11 g sodium chloride/d, was higher than advised.

4. It is concluded that the amounts of As, Br and toxic heavy metals in Dutch total-diet samples of male adolescents are of little concern as regards health aspects. Among the essential trace elements, Fe and Cu contents seem to be marginal. Some concern regarding the salt content is indicated.
Effects of guar gum on plasma urea, insulin and glucose in the growing pig
Authors: MalmlÖf Kjell , Nunes Carlos Simoes , Askbrant Stefan
Published: June 2005

1. Six growing pigs fitted with portal and arterial blood cannulas were given a barley-fishmeal diet, either alone or supplemented with guar gum at 60 g/kg basal diet. Blood samples were taken during 8 h following test meals given at 08.00 hours.

2. Ingestion of the guar-gum-supplemented diet appeared to increase systematically portal and arterial levels of plasma urea. At peak values, 4 and 5 h after the test meal, this effect was statistically significant (P <0.05).

3. Irrespective of which diet was given, portal and arterial blood samples, withdrawn at the same time, were found to have about the same concentration of urea. This was found throughout the 8 h studied and implies that no net exchange of urea between the circulation and the gastrointestinal tract, as a whole, took place.

4. In the time-period 30–60 min following the test meal, guar gum significantly reduced the postprandial hyperglycaemia and hyperinsulinaemia in portal blood.
Associative effects between two fibre sources on ileal and overall digestibilities of amino acids, energy and cell-wall components in growing pigs
Authors: Laplace J. P. , Darcy-Vrillon Beatrice , PÉrez J. M. , Henry Y. , Giger Sylvie , Sauvant D.
Published: June 2005

1. The associative effects of two fibre sources on ileal and overall digestibility of amino acids, energy and cell-wall components were studied by comparing wheat bran and soya-bean hulls in semi-purified diets given to growing pigs.

2. Castrated male pigs were prepared with ileo-rectal anastomosis to measure ileal digestibility, and overall digestibility was measured in pigs without anastomosis.

3. The three diets contained 190 g total fibre/kg dry matter (DM), derived from each fibre source or from a mixture of both fibre sources, so that each source provided half the amount of total fibre, and 170 g crude protein (nitrogen x 6·25)/kg DM by additions of casein.

4. The effects of fibre sources on the ileal digestibility of amino acids were additive for most amino acids; the only significant interactions were found for threonine, methionine and aspartic acid. In contrast with ileal digestibility, systematic negative interactions between fibre sources on overall digestibility of amino acids were noted.

5. There was no interaction between fibre sources in their effects on the digestibility of energy or of cell-wall components, irrespective of the site of digestion. The digestibility values were higher with soya-bean hulls than with wheat bran, especially at the faecal level.

6. It is concluded that ileal digestibility of amino acids provides a better estimate of amino acid availability, as ileal measurements allow a better discrimination between diets than faecal measurements when distinct fibre sources are used alone or in combination at the same total fibre content. In contrast, for energy, the measurement of digestibility at both faecal and ileal levels permits the estimation of the partition of available nutrients between the small and large intestines.
The importance of the form of nitrogen on microbial protein synthesis in the rumen of cattle receiving grass silage and continuous intrarumen infusions of sucrose
Authors: Rooke J. A. , Armstrong D. G.
Published: June 2005

1. In a 4x4 Latin square design experiment, four cattle were given grass silage in two meals per d to satisfy maintenance energy requirements. In addition, sucrose (170 g/kg silage dry matter (DM)) was infused intraruminally at a constant rate with no nitrogen supplementation; with the infusion intraruminally of either casein (23 g/kg silage DM) or urea (8 g/kg silage DM); or with soya-bean meal (64 g/kg silage DM) fed in two equal portions.

2. Samples of duodenal digesta representative of a 24 h period were obtained using chromium-EDTA and ytterbium acetate for flow estimation and35S as a marker of microbial N entering the small intestine. Samples of rumen fluid were also taken for estimation of rumen pH and concentrations of ammonia-N and volatile fatty acids. Estimates of apparent organic matter (OM) and N digestibility and of the rates of silage DM and N disappearance from porous synthetic-fibre bags incubated in the rumen were also made.

3. The N supplements had no significant effects on rumen pH, concentrations of volatile fatty acids, their molar proportions or the disappearance of DM or N from porous synthetic-fibre bags. N supplementation increased rumen ammonia-N concentrations (urea,P< 0.05; casein, soya-bean meal, not significant).

4. N supplementation had no significant effects on the digestion of OM, acid-detergent fibre or soluble carbohydrate.

5. Infusion of casein increased the quantities of total non-ammonia-N (not significant) and microbial N (P< 0.05) entering the small intestine daily and the efficiency of rumen microbial N synthesis (not significant). Giving soya-bean meal twice daily resulted in marginal increases in the quantities of non-ammonia-N and microbial N entering the small intestine, while infusing urea intraruminally had no effect.
Validity of a short food frequency questionnaire for estimating nutrient intake in elderly people
Authors: Horwath C. C.
Published: June 2005

Nutrient intakes estimated using a short self-administered semi-quantitative food frequency questionnaire (FFQ) were compared with results obtained from five 2 d diet records using household measures in a group of fifty-three elderly people (mean age 70 years) in Dunedin, New Zealand in 1989. Mean intakes for most nutrients were less than 5% different between the two methods. Correlations between the nutrient intake values (excluding supplements) from the diet records and those from the FFQ ranged from 0·34 for Zn in women to more than 0·75 for protein, Zn and Ca in men. For most nutrients, at least 70% of the subjects when classified by the food records fell into the same quintile or into the within-one- quintile category when classified by the FFQ. These data indicate that in elderly subjects a simple self- administered semi-quantitative FFQ can provide very similar information (for both group and individual intakes for many nutrients) to that obtained from 10 d of careful diet recording.