bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increase in the ileal absorption rate of sodium taurocholate in germ-free or conventional rats given an amylomaize-starch diet
Authors: Riottot M. , Sacquet E. 
Published: May 2005

1. Twenty germ-free and twenty conventional male Fischer 344 rats, 3 months old, were fed ad lib. diets based either on normal or on amylomaize starch for 1 month. The absorption rate of sodium taurocholate. 25 mmol/l, was determined in vivo in jejunal or ileal segments. Each determination included five rats.2. Jejunal absorption rate was not modified either by the amylomaize-based diet or by the digestive microflora.3. Ileal absorption rate was slightly higher in germ-free than in conventional rats.4. Ileal absorption rate was largely increased by the amylomaize-based diet. This increase was slightly larger in germ-free rats than in conventional rats.5. It is suggested that dietary amylomaize starch has an action on the active absorption process of bile acid.
The effect of lumen conditions on oxygen uptake in perfused omasal laminae
Authors: Lozeman F. J. , Milligan L. P. 
Published: May 2005

1. The vascular anatomy of the bovine omasal lamina permitted perfusion of a discrete area of the tissue. As occurs in vivo, oxygen was provided through the vascular system, while the luminal sides of the tissue could be kept in an anaerobic environment, thus allowing study of foregut tissue metabolism under physiologically realistic conditions.2. O2consumption of perfused leaves in the presence of anaerobic buffer was 64.9 and 73.5 nmol O2/mg dry weight per h in Expts 1 and 2 respectively, and was elevated (P< 0.05) when the lumen side of the tissue was exposed to an atmosphere of nitrogen gas.3. In Expt 1, the rate of O2consumption was increased (P< 0.01) by 35% as a result of suspension of a boiled preparation of rumen micro-organisms and particles (< 1 mm) in the anaerobic lumen buffer. Replacement of the boiled preparation with an unboiled suspension increased O2consumption further by 11 %, but this was not statistically significant (P> 0.05).4. In Expt 2, sequential addition of the following substrates or preparations to the lumen chambers all resulted in stepwise increases (P< 0.05) in O2consumption; 8 mM-butyrate, boiled rumen micro-organisms and particles and, finally, unboiled rumen micro-organisms and particles.5. Identities of the heat-labile and heat-stable components of the microbial and particle suspensions that caused enhancement of O2removal across the perfused tissue are discussed.
Performance of dairy cows offered isonitrogenous diets containing urea or fishmeal in early and in mid-lactation
Authors: Oldham J. D. , Napper D. J. , Smith T. , Fulford Rosemary J. 
Published: May 2005

1. Sixteen Friesian cows were used in Expt 1 to measure the effect of substituting urea-N with fishmeal-N either in early lactation (Part 1) or in mid-lactation (Part 2).2. In Part 1 (days 15–84 of lactation) the major N constituent of the concentrate was urea (U), urea-N: fishmeal-N in the ratio 2:1 (UF) or 1:2 (FU), or fishmeal (F). In Part 2 (days 84–1 75 of lactation) only urea (UM) and fishmeal (FM) were used.3. Replacement of urea-N with fishmeal-N significantly (P < 0.05) increased yield of milk protein both in early and in mid-lactation. At both stages of lactation the cows were, by calculation, in positive energy balance. In mid-lactation replacement of urea-N by fishmeal-N significantly depressed (P < 0.001) the concentration of fat in milk.4. Blood urea concentration decreased with increasing fishmeal inclusion (P < 0.05) from U to FU.5. In Expt 2 the diets used in Expt 1, Part 1, were offered at a maintenance level of feeding to non-pregnant, non-lactating heifers in a 4 x 4 Latin square design experiment. Digestibility of dry matter, organic matter and cell-wall constituents increased progressively (P < 0.05) with the first two increments of fishmeal inclusion.6. A major effect of replacing urea-N with fishmeal-N was to increase digestible organic matter intake (DOMI) and differences in DOMI between treatments in Expt 1, Part 1, accounted for observed differences in performance.
Effect of dietary protein concentration and ambient temperature on the energy, protein and water metabolism of the rat
Authors: Harri M. , Brockway J. M. 
Published: May 2005

1. Groups of rats (n 8) were offered, to appetite, diets containing 10 (LP), 25 (MP) and 45 (HP)% of gross energy as protein energy from 45 d of age to slaughter 50 d later. At 53 d of age, half the rats on each diet were left at 22°while the other half were transferred to 6°. Water balances were measured daily, and digestibilities of energy and nitrogen and the metabolizability of the diets were measured for each rat over a 7 d period at some stage between the age of 74 and 95 d. The rats were slaughtered at day 95 and their carcasses were analysed for protein, lipid, energy and ash contents. Energy expenditure was calculated as the difference between metabolizable energy intake and energy retained.2. Growth performance was best on the MP diet at both temperatures. At 22° the rate of gain of body-weight and of energy retention, although not of protein, were slightly reduced on the HP diet while overall performance was markedly inferior on the LP diet. At 6° the LP diet, while not so good as the MP diet, led to significantly better all-round growth performance than did the HP diet. Cold increased the energy expenditure of the rats by 50% (109–138 kJ/d); the increase was greater for the LP group than for the HP group.3. Intrascapular brown adipose tissue hypertrophied in response to cold and to the LP diet.4. Adrenal gland size was significantly increased by cold exposure and by increasing level of dietary protein concentration.5. Urine volume was more closely related to the intake of protein than to that of energy. Urinary N concentration for the HP rats was approximately double that for those on the LP diet. Cold-exposed rats had a high water content in their fat-free carcasses, but there were no differences between the dietary treatments.
The relation between food intake and abomasal emptying and small intestinal transit time in sheep
Authors: Gregory P. C. , Miller S. J. , Brewer A. C. 
Published: May 2005

1. The relation between the level of food intake and gastrointestinal motility and digesta flow in the abomasum and small intestine was studied in sheep fitted with nichrome-wire electrodes in the gut wall, an abomasal and a duodenal catheter and a terminal ileal cannula.2. Abomasal volume and outflow were calculated from CrEDTA dilution in six sheep and small intestinal transit time by the passage of Phenol Red in ten sheep.3. The frequency of the migrating myoelectric complex of the small intestine was not altered by the level of food intake but the duration of the periods of irregular spiking activity, the amplitude of abomasal activity and the frequency of duodenal rushes were decreased as the level of food intake was decreased.4. There was a linear relation between the level of food intake (FI) and abomasal outflow (mean with SEM: 327 (69) ml/h for each kg FI/d; P < 0.01), and abomasal volume (mean with SEM: 344 (50) ml/kg FI per d; P < 0.001), without any significant change in the half-time of marker dilution in the abomasum. Small intestinal transit time decreased with an increase in food intake (mean with SEM: - 54.9 (5.6) min/kg FI per d; P < 0.001).5.It is concluded that abomasal volume and the rate of digesta flow from the abomasum and along the small intestine are linearly related to the level of food intake.
The utilization by pigs of methionine from five protein concentrates compared with synthetic methionine
Authors: Leibholz Jane , Kirby A. C. 
Published: May 2005

1. Pigs (n 100) between 28 and 56 d of age were given diets containing one of five protein concentrates ad lib.2. The utilization of methionine from the protein concentrates was compared with synthetic methionine.3. Increasing the methionine content of the diets from 1.5 to 2.2 g/kg diet increased the weight gains of the pigs from 61 g/d to 198–292 g/d. The feed conversion efficiencies decreased from 2.56 to 1.34– 1.56.4. The utilization of methionine from the protein concentrates for weight gain, as compared with synthetic methionine, was meat meal A 0.89, meat meal B 0.97, soya-bean meal 1.02, cotton-seed meal 0.87 and dried skim milk 1.04.
Adsorption of soluble proteins to rumen bacteria and the role of adsorption in proteolysis
Authors: Wallace R. J. 
Published: May 2005

1. Following the addition ofI4C-labelled casein to mixed rumen bacteria at 39°, some radioactivity was adsorbed to the bacteria before the casein was hydrolysed. At O°, the rate of hydrolysis was greatly diminished but adsorption still occurred, and this enabled a study of the adsorption mechanism to be made.2. The adsorption of14C-labelled casein to rumen bacteria was a saturable process. The maximum binding capacity was about 10 μI4C-labelled casein/mg bacterial protein.3. The ability of bacteria to adsorb14C-labelled casein was abolished when they had been boiled for 5 min. Boiling caused the release of material from the bacteria which rendered some undigested protein soluble in 50 g trichloroacetic acid/l.4. Adsorbed14C-labelled casein could be partly displaced by the addition of Triton XI00 or an excess of unlabelled casein, or by boiling, or by removal of capsular material by blending. Adsorbed14C-labelled haemoglobin could similarly be displaced by an excess of cold casein.5. When an excess of casein was added to bacteria to which glucose-6-phosphate dehydrogenase (EC I. I.I.49) and glucosephosphate isomerase (EC 5.3. I.9) had been adsorbed, little active enzyme was displaced.6. The susceptibility of different14C-labelled proteins to hydrolysis corresponded to their relative adsorption affinities.7. The pattern of sensitivity to inhibitors of the adsorption mechanism was the same as that for the inhibition of the bacterial hydrolysis of 14C-labelled casein, and the synthetic substrates leucine p-nitroanilide and benzoyl arginine p-nitroanilide.8. It was concluded that the adsorption site and the catalytic site for proteolysis by rumen bacteria are probably identical and so not likely to be subject to independent manipulation.
Breast-milk production and energy exchange in human lactation
Authors: English R. M. 
Published: May 2005

1. The milk production of one mother was determined post-partum for a period of 13 weeks, during which time breast milk was her infant's only source of food energy. The weight changes of both the mother and the male infant were recorded during this period.2. The food intake and activity pattern of the mother were also recorded for 4-week periods: at 2, 6, 10 weeks after birth and 2 weeks after the cessation of lactation, which was maintained for a period of 27 weeks.3. The infant regained his birth weight of 3310 g on the 14th day of life. His weight gain for the duration of the study, which averaged 233 g/week, was considered satisfactory.4. The daily milk production increased gradually from an average of 241 g during the 1st week post-partum to 995 g during the 12th week. The infant's maximum milk intake and hence food energy intake per kg body-weight was (range) 198–204 g milk and 550–560kJ/kg respectively during the 3rd to the 7th week, followed by a gradual decrease from the 8th to the 13th week after birth.5. The estimated efficiency of energy coversion for breast-milk production was consistent with other values reported in the literature.
Thiamin status in normal and malnourished children in Jamaica
Authors: Hailemariam B. , Landman J. P. , Jackson Alan A. 
Published: May 2005

1. Thiamin status has been measured using the erythrocyte transketolase (EC 2.2.1.1) assay in twenty-eight normal children and in twenty-five severely-malnourished children throughout the course of recovery.2. Subclinical thiamin deficiency was found in 7% of the normal children and 36% of the malnourished children on admission.3. There was no significant association between thiamin status and oedema, stunting or wasting, history of breast-feeding, pattern of weaning, age or sex.4. Five malnourished children, who died, all had a normal thiamin status on admission; however, two developed biochemical evidence of thiamin deficiency preterminally.
The digestion of fibre by pigs
Authors: Stanogias George , Pearcet G. R. 
Published: May 2005

1. The effects of the amount and the type of dietary fibre on the apparent digestibility (AD) by growing pigs of neutral-detergent fibre (NDF) and NDF components, on nitrogen balance and on the rate of passage of digesta were studied using a semi-purified basal diet and fibre in the forms of soya-bean hulls, lupin (Lupinus sp.) hulls, pea (Pisum sativum) hulls, wheat bran, maize hulls, maize cobs, oat hulls and lucerne (Medicago sativa) stems.2. Both the amount and the type of dietary fibre significantly influenced the AD of dietary dry matter, N and energy. The AD of NDF and of NDF components was markedly affected by the type and the amount of fibre in the diet. The proportion of NDF digested ranged from 0.016 to 0.905, of cellulose from 0.026 to 0.931 and of hemicellulose from 0.010 to 0.999.3. N retention by the pigs ranged from 12.9 to 25.8 g/d and with some fibres there was a tendency towards increased N retention with increasing intakes of NDF.4. Rate of passage of digesta, expressed as the 50 and 95% excretion times of stained feed particles, ranged from 22.2 to 85.1 h and 40.0 to 117.1 h respectively. Large individual variations in rate of passage occurred but, in general, the rate of passage tended to increase with increasing intakes of NDF. No strong associations between the rate of passage of digesta and apparent digestibility of NDF components were observed.5. The results suggest that the extent of fibre digestibility depends predominantly on the origin of the fibre and to a lesser extent on the amount of fibre in the diet.
Nutritional availability of methionine, lysine and tryptophan in fish meals, as assessed with biological, microbiological and dye-binding assay procedures
Authors: Hewitt D. , Ford J. E. 
Published: May 2005

1. In vitro assay procedures were applied in the measurement of available amino acids in a selection of fish meals representing good- and poor-quality product. Results were assessed by comparing them with results from chick-growth assays.2. Available methionine and tryptophan were assayed microbiologically with Streptococcus zymogenes, after predigestion of the test samples with papain or pronase. Results for methionine were correlated with chick-growth assays (r 0.86 for papain, 0.91 for pronase; P < 0.01). Compared with the chick assays, papain tended to give lower, and pronase higher, results. Finer milling of the test samples did not influence the pronase values.3. Results for available tryptophan were also correlated with chick-growth assays (r 0.95 for papain, 0.96 for pronase; P < 0.001). Compared with the chick values, papain gave markedly lower results and pronasem marginally higher ones. Finer milling of the test samples increased the papain values by about 50% but had no effect with pronase.4. Available lysine was assayed microbiologically with Tetrahymena pyriformis and with a dye-binding procedure (DBL). The results correlated with the chick-growth assays (r 0.99 for DBL, P < 0.001; 0.85 for Tetrahymena, P < 0.01) but both methods overrated the poorer-quality samples.5. True nitrogen digestibilities and amino acid digestibilities were determined with chickens by the 'ileal analysis' procedure: the amino acid digestibilities were significantly higher and similar to the corresponding availabilities as measured in chick-growth assays.6. Ball milling a poor-quality fish meal caused a marked fall in its N digestibility, whereas similar treatment of a good-quality meal caused a slight increase. An explanation for this finding is proposed.7. Strep. zymogenes assays following pronase digestion of the test samples gave precise and acceptably accurate measures of the biologically available methionine and tryptophan in the test samples. For available lysine, Tetrahymena and DBL values for the poorer-quality samples were notably higher than the chick-growth assay; possible reasons for this are discussed. The ileal analysis procedure underestimated true N digestibility.
An evaluation of total and digestible lysine as a predictor of lysine availability in protein concentrates for young pigs
Authors: Leibholz Jane 
Published: May 2005

1. Forty pigs between 23 and 51 d of age were given,ad lib., diets containing 7.9 g lysine/kg. The diets contained wheat and one of five protein concentrates: milk, peanut (Arachis hypogaea) meal, cotton-seed (Gossypium herbaceum) meal, meat meal or lupins (Lupinus augustifolius).2. Twenty of the pigs were given an indigestible marker,103Ru-labelled Tris-(1, 10-phenanthro1ine)-rthenium(II) chloride, between 51 and 56 d of age and were killed at 56 d of age.3. A further forty pigs, between 23 and 51 d of age, were given the same diets supplemented with 3 g L-lysine hydrochloride/kg.4. The weight gains of the pigs given the diets containing 7.9 g lysine/kg (95–153 g/d) were significantly less (P< 0.05) than those of the pigs given the diets containing 10.9 g lysine/kg (274–340 g/d).5. Weight gains of pigs given the diets containing meat meal were less than those of pigs given diets containing milk, peanut meal or lupins.6. Feed conversion ratios decreased and N balances increased with increasing lysine content of the diets.7. Apparent digestibilities of dry matter (DM) and nitrogen of the diets containing meat meal and cotton-seed meal were less than those of the other three diets, but there was no effect of lysine content of the diets on these indices.8. The major site of DM and N absorption for the diet containing milk was the duodenum while for the other four protein concentrates the jejunum and ileum were the major absorption sites.9. Apparent digestibility of lysine from the five diets ranged from 0.54 to 0.75. The retention of the apparently absorbed lysine in weight gain was 0.8–0.94, and there was no significant (P > 0.05) difference between diets which suggested that the apparent digestibility of lysine could be an indicator of its availability.
Utilization of low-quality roughage byBos taurusandBos indicuscattle
Authors: Hunter R. A. , Siebert B. D. 
Published: May 2005

1. In a number of experiments voluntary food intake of three low-quality roughages, either alone or supplemented with rumen-degradable nitrogen and sulphur and minerals, was measured in Brahman (Bos indicus) and Hereford (Bos taurus) steers. The chaffed hays were Spear grass (Heteropogon conform) (6.2 g N/kg organic matter (OM)), Pangola grass (Digitaria decumbens) (7.9 g N/kg OM), and Pangola grass (12.0 g N/kg OM). Rumen characteristics relating to rate of fluid outflow from the rumen were also determined.2. There was no significant difference between breeds in the dry-matter intakes of the unsupplemented diets which ranged from 11.3 to 17.8 g/kg body-weight (BW) by Herefords and from 11.8 to 16.1 g/kg BW by Brahmans.3. Supplementation of Spear grass with N and S significantly (P < 0.05) increased intake by Herefords (24%) but not by Brahmans. When the lower-N Pangola grass was supplemented there was a significant increase in intake by both breeds with the magnitude of the response in Herefords (42%) (P < 0.001) being greater than that in Brahmans (15%) (P < 0.05). The intakes of both the supplemented Spear grass and the lower-N Pangola diets were significantly (P < 0.05) greater by Herefords than Brahmans. There was no breed difference in intake when the higher-N Pangola grass was supplemented. Both breeds recorded an 8% intake response to supplementation, although the increase was only significant (P < 0.05) in Herefords.4. The mean retention time of fluid in the rumen on the unsupplemented Pangola grass diet of lower N content was 12.7 h in Brahmans compared with 17.5 h in Herefords (P < 0.01). When the higher-N Pangola was fed, both alone and supplemented, the mean retention times were similar on both diets (10.5 and 9.9 h for Herefords; 9.5 and 8.1 h for Brahmans for unsupplemented and supplemented diets respectively).5. Plasma urea concentrations were higher in Brahmans than in Herefords on all diets. Rumen ammonia concentrations were significantly (P < 0.001) higher in Brahmans than Herefords when the lower-N Pangola grass diet was unsupplemented.6. The intakes and the variable intake responses to supplementation between breeds and diets are discussed in relation to a number of animal and dietary factors.
Plasma amino acids and tissue methionine levels in fruit bats (Rousettus aegyptiacus) with nitrous oxide-induced vitamin B12deficiency
Authors: Van Der Westhuyzen Justin , Van Tonder Suasn V. , Gibson Jayne E. , Kilroe-smith Terence A. , Metz Jack 
Published: May 2005

1. The effect of methylcobalamin inactivation by the gas nitrous oxide on plasma amino acid and tissue methionine levels in fruit bats (Rousettus aegyptiacus) was examined.2. Animals exposed to N2O-oxygen (1:1, v/v) for 90 min daily received a fruit diet with or without methionine or betaine supplements. Exposure and diets were continued for up to 17 weeks or until neurological impairment and muscular weakness was established.3. All the groups exposed to N2O had significantly lower liver, brain and plasma methionine concentrations except the methionine-supplemented animals which showed significantly raised levels. Plasma homocysteine, which was absent in controls, was present in all the N2O-exposed groups.4. Betaine supplementation resulted in reduced accumulation of homocysteine in plasma. However, plasma and liver methionine levels were only slightly increased compared with animals on the basal diet, and brain methionine levels were the lowest of all the groups studied.5. These results support the hypothesis that reduced methionine synthesis is an important contributor to the development of neurological impairment in this species and suggest that dietary supplementation with the methionine precursor betaine cannot replace the loss of vitamin B12-dependent methionine synthesis.
All-trans-retinoic acid inhibits retinol esterification by acyl-CoA: retinol acyltransferase (EC2.3.1.76) from rat and human small intestinal mucosa
Authors: Hanne Müller , Norum Kaare R. 
Published: May 2005

1. Formation of retinyl esters catalyzed by acyl-CoA: retinol acyltransferase (ARAT; retinol fatty- acyltransferase; EC 2.3.1.76) from intestinal mucosa has been studied in vitro in the presence of all-trans-retinoic acid.2. The incubation system contained microsomal preparations from the tissue tested, radioactive retinol and palmitoyl-CoA. The product formed was separated from the substrates by chromatography on alumina columns.3. All-trans-retinoic acid inhibited ARAT both from rat and human intestinal mucosa.4. Inhibition occurred instantly. At a concentration of retinol of 80, μM, a 50% inhibition was obtained with 50 μM- retinoic acid.5. The inhibition of ARAT by retinoic acid may be of importance for normal retinol absorption in patients receiving retinoid therapy.