1. Antlers were removed in September from 2-4-year-old red deer (Cervus elaphus L.). Both well-fed penned stags and less. well-nourished grazing stags were studied.

2. For deer of the same age, both log antler weight and log antler specific gravity were related to body-weight in September and to body-weight gain between March and September. The antlers of 3- and 4-year-old stags were heavier and tended to be denser relative to body-weight and body-weight gain than those of 2-year-old stags.

3. For grazing stags of a given age, antler weight and specific gravity, and body-weight and body-weight gain, were progressively less in the three successive years of the study. This appeared to reflect increasing stocking rate over this period.

4. The composition of the antlers did not vary significantly between penned and grazing stags or with age. However the concentrations of ash, phosphorus and magnesium in dry matter showed significant positive correlations with specific gravity, that of zinc a significant negative correlation, while calcium, copper and manganese showed no significant correlation.

5. The antlers evidently provide a useful index of the changes in body-weight of the stags.

1. 1. To study the potential of the constant-infusion technique for measuring rates of protein synthesis in New Zealand White rabbits, animals were infused for up to 6 h with radioactively-labelled tyrosine.

2. 2. Labelled tyrosine from plasma and tissues was isolated from labelled metabolites by ion-exchange chromatography.

3. 3. Analysis of serial blood and muscle biopsy samples removed under anaesthesia showed that the specific radioactivity (SR) of the free tyrosine pools reached an approximately constant value within 2 h.

4. 4. Certain commercial preparations of L-[side-chain 2,3-3H]tyrosine were contaminated with 300 mg radioactive D-tyrosine/g. The D-isomer appeared to enter the muscle intracellular pool.

5. 5. In constant-infusion experiments L-[3H]tyrosine could replace the uniformly-14C-labelled L-isomer for the determination of rates of protein synthesis in muscle. L-[side-chain 2,3-3H]tyrosine may not be suitable for use as a precursor for measuring rates of liver protein synthesis.

6. 6. Evidence is presented that the precursor of liver protein synthesis may not be well defined by the SR for free tyrosine of the homogenate.

7. 7. The technique was used to measure the rates of protein synthesis in adult rabbits. The rates of protein synthesis in liver and muscle were measured and from measurements of tyrosine flux the mean rate of whole-body protein synthesis was calculated as 13.8 g/kg per d.

1. It has been observed previously that gastrocnemius muscles from rats rehabilitated after early nutritional stress have low endurance and oxidative capacity (Raju, 1974).

2. Exercise during rehabilitation reversed the effects of early malnutrition on muscle function and metabolism. The swimming performance of rehabilitated rats was poor and exercise during rehabilitation improved it.

3. The specific activity of gastrocnemius muscle myosin ATP phosphohydrolase (EC 3.6.1.3) was not altered by either early malnutrition or exercise.

1. Three groups of cockerels were reared from 3 to 11 weeks of age on increasingly severe quantitative food restriction treatments, resulting in body-weight values of 12, 19 and 27% below that of a control group which was fed ab lib.

2. The rate of uptake of L-arginine, glycine, L-lysine and L-phenylalanine was measured in vitro using intestinal rings, over a 5 min incubation period.

3. Uptake of L-arginine was significantly increased with increasing degrees of body-weight restriction. This amino acid and L-lysine were the only two to show a significantly enhanced uptake rate as a result of the restriction treatments.

4. No significant differences were noted in the case of glycine or L-phenylalanine uptake following food restriction, indicating a certain selectivity in the alteration of absorption rates following food restriction, when such tests are conducted in vitro.

1. 1. [75Se]selenite or [75Selenomethionine was injected into the coelomic cavity of fish. After 2 d or 14 d the muscle portion of the fish was removed and homogenized. The long-term fate in rats of an oral dose of each labelled homogenate was compared with that of an oral dose of [75Se]selenite or [75Se]selenomethionine mixed with unlabelled fish homogenate.

2. 2. Urinary and faecal radioactivity were measured during the 1st week and whole-body radioactivity was determined for 10 weeks. Rats were killed at weekly intervals for 4 weeks for analysis of tissue distribution of 75Se.

3. 3. Intestinal absorption of 75Se given as labelled fish homogenate was less complete than that of 75Se mixed with unlabelled homogenate, and the absorption of 75Se from the 14d-labelled fish homogenate derived from [75Se]selenite was less complete than that of 75Se from the other labelled homogenates.

4. 4. Urinary excretion of absorbed 75Se in the first 7 d was in the range 5-8 % absorbed dose and was slightly greater in the rats given 75Se as selenite or derived from selenite than in those given 75Se as selenomethionine or derived from selenomethionine. Endogenous faecal excretion of absorbed Se was similar in all groups, as also were tissue distribution of retained 75Se and long-term whole-body turnover rate.

5. 5. The results of these studies are compared with those of earlier studies of the metabolism in rats of [75Selenomethionine, [75Se]selenite, [75Sejselenocystine and 75Se incorporated in vivo into rabbit kidney. There were differences in the initial utilization of 75Se from these various sources but after the 1st week 75Se from all sources appeared to be metabolized similarly, suggesting that for rats dietary Se of all forms is ultimately incorporated into the same metabolic pool.

1. Milk-substitute diets, in which 330-360 (L) or 610-700 (H) g/kg milk protein was replaced by protein from a thermo-alkali-treated soya-bean flour (SF) or from fish-protein concentrate (FPC), were compared in an experiment involving fifty Friesian calves, of which half were supplemented with a growth promoter, Grofas, known to have bacteriostatic properties. The liquid diets were fed ad lib. from 48 h of age until 136 kg live weight.

2. Seven calves, given non-milk protein, died or were removed from the experiment. There was little difference between treatments in the incidence of diarrhoea or in other observations on health of surviving calves, but those given non-milk protein maintained a lower mean rectal temperature.

3. Weight gain was reduced, especially during the first 3 weeks of life, by inclusion of non-milk protein. The reduction was greater for SF than for FPC, and greater at the H level. Supplementation with Grofas improved weight gain for calves given non-milk protein, but tended to reduce that for calves given milk protein.

4. Apparent digestibility of dry matter and protein was reduced when non-milk protein was used. The reduction was greatest at a young age, greater for SF than for FPC and greater at the H level. Apparent digestibility of fat was most markedly reduced with FPC, especially at 1 week of age, and was increased by Grofas supplementation. Digestibility of the carbohydrate in SF was low at 1 week but increased with age. Grofas supplementation caused a marked reduction in the disappearance of SF-carbohydrate in the alimentary tract. Apparent absorption of ash and calcium were reduced by non-milk protein, especially by FPC. The reduction in absorption of ash from SF was moderated by Grofas supplementation. Although Ca retention for calves given SF at the H level was very low, no bone defects were observed.

5. Nitrogen retention was slightly lower for calves given non-milk protein, but the efficiency of retention of apparently digested N was greater for calves given non-milk protein because of the much reduced urinary N excretion associated with a lower apparently digested N intake.

6. Dressed-carcass weight and ‘killing out’ percentage were lower for calves given non-milk protein, especially SF at the H level. Adrenal weights were markedly increased by feeding SF especially at the H level. Pancreas weight was greater for calves given SF than for those given FPC.

7. Weight of abomasal contents at slaughter was much lower for calves given non-milk protein. Weight of intestinal tissue and of total tissue in the alimentary tract were markedly increased by non-milk protein, especially by SF at the H level, and reduced by Grofas supplementation. The increased weight was associated with increased thickening of the walls of both the small and large intestine, which was possibly associated with hypertrophy of muscle cells.

8. It is concluded that up to 360 g/kg milk protein could be replaced by protein from this thermo-alkalitreated SF, and up to 610 g/kg milk protein from this FPC without markedly affecting performance, especially if an effective growth promoter is included in the diet. The beneficial effect of Grofas appeared to result from the reduction in the fermentation of the oligosaccharides of SF, which was reflected in higher digestibility particularly of fat and absorption of Ca and in reduced thickness of the intestines.

1. 1. The concentrations of serum protein albumin, prealbumin and transferrin were determined in twentyeight cases of protein-energy malnutrition (PEM) with infection, together with the levels of serum proteinase inhibitors (PI), α1-antitrypsin (AT), α1-antichymotrypsin (Ach), α2-macroglobulin (α2M) and inter-α-trypsin inhibitor (IαI).

2. 2. Albumin, prealbumin and transferrin concentrations, as well as the levels of PI, IαI and α2M were found to be lower in cases of PEM associated with infection than the corresponding values for a group of healthy Thai preschool children and a group of newborn Thai children, but despite starvation AT and Ach values generally were increased.

3. 3. The results provide support for the hypothesis that PI, especially AT and Ach might limit the synthesis of albumin, prealbumin and transferrin in PEM associated with infection, via the inhibition of the mobilization of body's own protein.

1. The nutritional value of fish protein oxidized with different levels of hydrogen peroxide, and the utilization of oxidized sulphur-amino acids in the rat were investigated.

2. The results showed that the biological value (bv) and protein efficiency ratio (per) of the fish protein were significantly decreased by the treatment with H2O2, and although there were no significant differences between samples treated with 20, 40 or 80 g H2O2/kg, there was a gradual decrease of BV at higher concentrations. Digestibility was not affected by the treatment.

3. Supplementation with 1 g L-methionine/kg or 1 g L-cystine/kg significantly increased the BV for all H2O2-treated samples. With the exception of the sample treated with 80 g H2O2/kg, the BV was increased by L-methionine supplementation to the level for the untreated fish protein.

4. Treatment with H2O2 led to the formation of methionine sulphoxide, methionine sulphone and cysteic acid. The availability of these compounds was studied as supplements to the untreated fish protein as well as to the H2O2-treated fish protein. The results showed that L-methionine DL-sulphoxide was as available as methionine, but that L-methionine sulphone and cysteic acid had no supplementary effect.

5. The availability of lysine in fish protein was not affected by treatment with 20 g H2O2/kg as judged by its effect as a supplement to wheat flour.

6. The plasma amino acid pattern for rats given a diet with H2O2-treated fish protein was identical to that for rats given an untreated fish protein, with the exception of the presence of the two isomers of L-methionine DL-sulphoxide and L-methionine sulphone. The oxidized S-amino acids were also found in liver, kidney and gastrocnemius muscle from the rat.

7. Only traces of L-methionine DL-sulphoxide were found in the urine. About half the ingested L-methionine sulphone was found in the urine and almost all was present as an acid-labile conjugate.

1. Fatty liver and kidney syndrome (FLKS) was induced in young broiler chickens by giving them a diet composed principally of wheat and meat meal.

2. FLKS resulted in reduced growth and increased liver weight; fasting for 18 h increased mortality, liver lipid and the specific activity of hepatic ATP-citrate lyase compared with birds fed on a commercial diet. The specific activities of hepatic fructose-l,6-diphosphate-l-phosphohydrolase and pyruvate carboxylase were reduced in birds suffering from FLKS and fasted for 18 h.

3. Feeding of the FLKS-inducing diet supplemented with 150 g animal tallow/kg for 54 h considerably reduced mortality while restoring liver composition and enzyme activities towards those observed in birds fed a commercial diet. Investigations indicated that the glycerol component of the fat was not responsible for the observed responses.

4. The present results suggest that in FLKS insufficiencies of biotin are induced in specific enzyme systems, but the syndrome may be alleviated without the use of supplementary biotin.

5. The evidence indicates that, when stressed, birds affected by FLKS die from the hypoglycaemia occurring as a result of a reduced capacity for gluconeogenesis.

1. 1. Six groups of rats were given diets containing protein at three levels (SO, 100 and 200 g/kg), with and without nicotinic acid. After 4 weeks on these diets some key enzymes of the tryptophan and nicotinic acid-NAD pathway, liver nicotinamide nucleotide concentration, and urinary metabolites of tryptophan and nicotinic acid were studied.

2. 2. Liver nicotinamide nucleotide levels were lower in rats given the diet with 50 g protein/kg as compared to those in rats given diets with 100 and 200 g protein/kg. The addition of nicotinic acid to the diet resulted in a significant increase in the levels of nicotinamide nucleotides only in rats given 50 g protein/kg diet but not in those given either 100 or 200 g protein/kg diet.

3. 3. Liver tryptophan oxygenase (EC 1.13.1.12) activity increased with increasing dietary protein level. Nicotinic acid in the diet had no effect on its activity.

4. 4. Quinolinate phosphoribosyltransferase (EC 2.4.2.a) activity in liver was inversely related to dietary protein level, and nicotinic acid in the diet had no effect on its activity.

5. 5. Liver nicotinate phosphoribosyltransferase (EC 2.4.2.11) activity and kidney picolinate carboxylase (EC 4.1.1.45) activity were not altered either by dietary protein level or nicotinic acid in the diet.

6. 6. The addition of nicotinic acid to the diet resulted in increased excretion of W-methylnicotinamide at all dietary protein levels.

7. 7. The inverse relationship between protein level in the diet and liver quinolinate phosphoribosyltransferase activity, the rate-limiting enzyme of the tryptophan-NAD pathway suggests that the efficiency of conversion of tryptophan to NAD is related to protein level in the diet, the efficiency decreasing with an increase in the level of dietary protein.

1. Mixed bacteria were obtained from the rumen contents of steers and were taken at different times after the animals had been given different feeds. The feeds contained [15N]urea and in some experiments Na235SO4 so that the bacteria were labelled with these isotopes.

2. Samples of labelled bacteria were subjected to a simulated abomasal digestion with pepsin and the digests were infused with a non-absorbed marker, polyethylene glycol, into the duodenums of test steers equipped with re-entrant ileal cannulas. Except for samples taken after a 24 h fast, which sometimes gave somewhat lower values, mean values for digestibilities of 15N and 35S in the small intestine were 0.79 and 0.85 respectively.

3. The corresponding value for the digestibility of 15N in similarly-treated wheat-leaf protein concentrate was 0.86.

4. Net digestibilities of total N in the small intestine of the test steers when they were given either a mainly protein-free diet of straw, tapioca and urea or a diet of flaked maize and hay were approximately 0.62.

5. From these and other values it was calculated that approximately 5.2g intestinally-secreted endogenous N/d flowed through the ileum of a 100 kg steer.

1. Fatty liver and kidney syndrome (FLKS) was induced in a proportion of a group of 4-week-old chickens by giving a diet of meat meal and wheat; inclusion in the diet of animal tallow for 54 h substantially reduced the occurrence of FLKS.

2. Measurements of dynamic aspects of glucose metabolism were made with single injections of [2-3H]glucose which indicated that birds given the ‘FLKS-inducing’ diet and showing physical symptoms of FLKS had significantly lower rates of synthesis of glucose than birds given either the same diet supplemented with tallow or a commercial diet.

3. In a second series of experiments glucose metabolism was studied in birds (1) with or without physical symptoms that were given the ‘FLKS-inducing’ diet and (2) birds given the same diet supplemented with tallow or biotin. Affected birds fed the ‘FLKS-inducing’ diet had significantly lower plasma glucose concentrations, pool sizes and synthesis rates than birds fed the same diet and not showing symptoms, or birds fed the supplemented diets.

4. It is suggested that the cause of death in birds with FLKS is a low rate of gluconeogenesis during periods without feed which results in a lack of glucose to meet essential functions.

1. The production rates of bacteria in the rumen of buffalo (Bos bubalis) calves were estimated using an isotope-dilution technique. A series of fifteen experiments was done with animals given green maize and nine experiments with animals given cowpea (Vigna unguiculata).

2. The turnover time ranged from 205 to 567 min in the group given green maize and from 330 to 648 min in animals offered cowpea. The production rates of bacteria were (mean±SE; g/d) 145.77±7.240 and 237.09±11.847 in animals given green maize and cowpea respectively.

3. There was a significant correlation between bacterial production rates and dry matter intake, digestible organic matter and total volatile fatty acids formed in the rumen.

4. Regression equations obtained for the two foodstuffs were different suggesting that the bacterial growth rate may vary depending upon the quantity and quality of foodstuff digested and possibly the ratio nitrogen: energy of the foodstuff.

1. 1. As most of the studies on the regulation of renal 25-hydroxycholecalciferol-1-hydroxylase (25-HCC-1-hydroxylase) activity have been done in marginally-vitamin D-defieient animals and as it is known that vitamin D administration suppresses the specific activity of the 25-HCC-1-hydroxylase, it was decided to study the effect of dietary calcium on the activity of 25-HCC-1-hydroxylase and on Ca absorption in vitamin Dreplete chicks.

2. 2. Chicks, 10 d old, were given diets differing in their Ca contents (65 nmol cholecalciferol/kg diet) for 10 d and the activity of 25-HCC-1-hydroxylase in kidney homogenates, Ca absorption from the duodenum, Cabinding protein (CaBP) activity in the duodenal mucosa and plasma Ca and phosphate concentrations were all determined.

3. 3. The CaBP activity and the efficiency of Ca absorption both decreased with increasing dietary intake of Ca. Ca absorption and CaBP activity were significantly correlated (r 0.995, P < 0.01).

4. 4. The activity of 25-HCC-1-hydroxylase decreased as the dietary level of Ca increased and was significantly correlated with Ca absorption (r0.900, P < 005). The plasma Ca concentration and the activity of 25-HCC-1-hydroxylase were inversely related (r-0.940, P < 0.01).

5. 5. It is concluded that in the vitamin D-replete chick the efficiency of duodenal Ca absorption is regulated by the renal 25-HCC-1-hydroxylase activity via production of 1,25-dihydroxycholecalciferol and CaBP synthesis.

1. Serial estimations of plasma (PAA) and leucocyte (LAA) ascorbic acid concentrations were made in geriatric patients in a stable phase of their illness, and compared with a similar (‘unstable’) group suffering from acute illness.

2. In the ‘unstable’ group, though PAA levels were unchanged, LAA levels were reduced.

3. In the ‘follow-up’ period of 7-8 d there was much greater variation in both PAA and LAA levels in the ‘unstable’ group.

4. Acute illness was often accompanied by an increase and then a decrease in LAA levels. Recovery was associated with an increase in LAA levels.

1. The galactolipids of heat-treated, 14C-labelled rye grass S24 administered intraruminally to a sheep fed on an autoclaved diet were rapidly catabolized.

2. When grass was homogenized with rumen contents devoid of higher plant lipases the grass galactolipids were rapidly metabolized, but were not metabolized when the rumen contents were boiled to destroy microbial galactolipases.

3. 14C-labelled monogalactosyldiglyceride, digalactosyldiglyceride and triolein were metabolized, with the release of 14C-labelled fatty acids when incubated with a homogenate (100 g/l) of grass or clover in rumen fluid from a starved sheep, but not when the rumen fluid was heat-treated to destroy microbial enzymes.

4. It is concluded that in the sheep the lipases of rumen micro-organisms play a major part in the ruminal degradation of ingested complex lipids of pasture.

1. 1. A total of 179 duplicate diets were collected by twenty-three women consuming their habitual diet. Twelve of the subjects were living in a residential hall for students, the others were living in their own homes or in flats. Collection periods varied from 3 to 21 d.

2. 2. Average daily intakes were: manganese 2.7 mg; copper 1.5 mg for diets not containing liver, 7.6 mg for fifteen diets containing liver; zinc 10.0 mg; cadmium 21 μg for diets not containing liver, 27μg for fifteen diets containing liver.

3. 3. The intakes were compared with values for adults from other countries and with current recommended dietary allowances or estimated minimum requirements. Mn intakes were typical for non-vegetarian Western diets. Cu and Zn intakes may have been marginally low. The intakes of Cd were low.

4. 4. Daily intakes of protein (71 g), fat (83 g), carbohydrate (224 g) and energy (8.1 MJ) from 129 of the diets were similar to recent values obtained for New Zealand women.

5. 5. Subjects living in the residential hall had higher intakes of all nutrients than subjects living in their own homes or flats.