Exercise prior to eating has repeatedly been shown to reduce postprandial lipaemia. The aim of the present study was to investigate whether this effect was manifest in the presence of two factors that independently mitigate postprandial lipaemia: eumenorrhoea and moderate fat intake. Eight healthy eumenorrhoeic rowers consumed a meal of moderate fat content (35% total energy, 0·66g/kg body mass) 14h after having either rowed at 55% of maximal aerobic power (81% of maximal heart rate) for 80min or rested. Both trials were performed during the luteal phase. Blood samples were drawn before the meal and for 8h postprandially for the measurement of individual fatty acids in the triacylglycerol and NEFA fractions, as well as of glucose, insulin and oestradiol. Plasma oestradiol concentrations were not significantly different in the two trials. The postprandial lipaemic response, expressed as either plasma triacylglycerol concentration or area under the triacylglycerol–time curve, was 35% lower (P<0·05) after exercise. The postprandial glycaemic and insulinaemic responses were also lower, indicating increased insulin sensitivity, whereas the NEFA response was higher, suggesting a lower entrapment of dietary fatty acids in adipose tissue after exercise. Finally, exercise increased the proportion of unsaturated:saturated NEFA during the postprandial period. In conclusion, aerobic exercise performed 14h before a moderate-fat meal reduced postprandial lipaemia in women in the luteal phase. This effect shows the potential of exercise to mitigate even moderate lipaemic responses in eumenorrhoeic women.

Peripheral vascular disease (PVD) is a manifestation of systemic atherosclerosis in the lower limbs, and PVD patients have a 3- to 5-fold increased risk of cardiovascular mortality compared with age-matched controls. Nevertheless, recent reports show how PVD patients are undertreated with regard to CVD risk-factor reduction and the use of lipid-lowering or antiplatelet drugs. There is appreciable evidence that demonstrates the beneficial effects of certain nutrients and dietary habits in the prevention of CVD, but there has been little attention paid to the role of nutrients in PVD. The purpose of the present review is to provide an overview of our understanding of how foods could possibly benefit PVD. In the last few decades, several nutrients have arisen as potentially health-promoting in PVD. While nutritional interventions in PVD show positive clinical effects for fish oil, carnitine or vitamin E, others such as olive oil or vitamin C seem to interact only at a biochemical level by decreasing risk factors. Moreover, only epidemiological associations exist for the potential role of fibre, folates or vitamin B6 in this disease. In all cases, the limited data available provide no clear-cut evidence in favour of the clinical benefit of nutritional interventions aimed at reducing risk factors and ameliorating symptoms in PVD patients. No practical recommendations can be given at this stage, and further studies are clearly needed.

Anecdotal evidence suggests the use of bolus tube feeding is increasing in the long-term home enteral tube feed (HETF) patients. A cross-sectional survey to assess the prevalence of bolus tube feeding and to characterise these patients was undertaken. Dietitians from ten centres across the UK collected data on all adult HETF patients on the dietetic caseload receiving bolus tube feeding (n 604, 60 % male, age 58 years). Demographic data, reasons for tube and bolus feeding, tube and equipment types, feeding method and patients’ complete tube feeding regimens were recorded. Over a third of patients receiving HETF used bolus feeding (37 %). Patients were long-term tube fed (4·1 years tube feeding, 3·5 years bolus tube feeding), living at home (71 %) and sedentary (70 %). The majority were head and neck cancer patients (22 %) who were significantly more active (79 %) and lived at home (97 %), while those with cerebral palsy (12 %) were typically younger (age 31 years) but sedentary (94 %). Most patients used bolus feeding as their sole feeding method (46 %), because it was quick and easy to use, as a top-up to oral diet or to mimic mealtimes. Importantly, oral nutritional supplements (ONS) were used for bolus feeding in 85 % of patients, with 51 % of these being compact-style ONS (2·4 kcal (10·0 kJ)/ml, 125 ml). This survey shows that bolus tube feeding is common among UK HETF patients, is used by a wide variety of patient groups and can be adapted to meet the needs of a variety of patients, clinical conditions, nutritional requirements and lifestyles.

1. All food was withdrawn from male weanling rats until a 40% loss of body-weight was attained. Another group of animals was treated similarly and then refed a stock diet until the original body-weight was attained.

2. The body-weight loss caused a significant reduction in the weight of the heart, kidney, liver and epididymal fat pads. Refeeding produced a return to the control weight of the heart and kidney, an increase in the weight of the liver and a deficit in the weight of the epididymal fat pads.

3. Body-weight loss caused a decrease in the weight of the three different muscles studied, and in the number and diameter of the fibres in each muscle. Refeeding restored the weight and cellularity of two of the three muscles to that of the control animals. The soleus muscle was heavier in the refed animals when compared to controls due to an increased fibre diameter.

4. It is concluded that the decrease in the number and diameter of muscle fibres during starvation in the rat can be restored on refeeding a stock diet.

Oxidative stress is a physiological condition that is associated with atherosclerosis, and it can be influenced by diet. Our objective was to group fifty-seven individuals with dyslipidaemia controlled by statins according to four oxidative biomarkers, and to evaluate the diet pattern and blood biochemistry differences between these groups. Blood samples were collected and the following parameters were evaluated: diet intake; plasma fatty acids; lipoprotein concentration; glucose; oxidised LDL (oxLDL); malondialdehyde (MDA); total antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing ability power assays. Individuals were separated into five groups by cluster analysis. All groups showed a difference with respect to at least one of the four oxidative stress biomarkers. The separation of individuals in the first axis was based upon their total antioxidant activity. Clusters located on the right side showed higher total antioxidant activity, higher myristic fatty acid and lower arachidonic fatty acid proportions than clusters located on the left side. A negative correlation was observed between DPPH and the peroxidability index. The second axis showed differences in oxidation status as measured by MDA and oxLDL concentrations. Clusters located on the upper side showed higher oxidative status and lower HDL cholesterol concentration than clusters located on the lower side. There were no differences in diet among the five clusters. Therefore, fatty acid synthesis and HDL cholesterol concentration seem to exert a more significant effect on the oxidative conditions of the individuals with dyslipidaemia controlled by statins than does their food intake.

1. An experiment was designed to provide information on the alterations in body metabolism which would account for the loss of body-weight in cattle due to the specific effect (factors other than reduced food intake) of the tick Boophilus microplus.

2. Two groups of British (Shorthorn × Hereford) and Africander × British calves, each approximately 6 months old, were used: one group (treated) of each breed was tick-infested and the other (control) was tick-free. Within breeds, calves in the control group were pair-fed to calves in the treated group.

3. In both breeds, the effect of ticks: (a) depressed packed cell volume, serum alkaline phosphatase (EC 3.1.3.1) and amylase (EC 3.2.1.1) activities, plasma cholesterol and phospholipid levels, serum iron and albumin levels. (b) increased the plasma levels of urea-nitrogen and γ-globulin (c) increased rectal temperature, water intake, urine volume, urinary and faecal total N, urinary urea-N and α-amino acids, the excretion of water, sodium and potassium in the faeces and (d) reduced N balance, N and dry-matter digestibilities.

4. In the British breed, ticks increased the excretion of K with a corresponding decrease in the excretion of Na in the urine and inreased the plasma clearance of bromsulphthalein.

5. A second experiment showed that the specific effect of tick infestation increased the flow of organic matter (OM) from the abomasum and the fractional turnover of rumen fluid of Hereford steers. It was also shown that the decrease in OM digestibility in the gastrointestinal tract was largely due to a decrease in OM digestibility in the rumen and that the increased urinary urea excretion and plasma urea concentration was caused by higher production rates of urea despite a tendency for lowered urea degradation in the gastroinestinal tract.

The current systematic review and meta-analysis were conducted to evaluate the effects of oral Mg supplementation on glycaemic control in type 2 diabetes mellitus (T2DM) patients. Related articles were found by searching the PubMed, SCOPUS, Embase and Web of Science databases (from inception to 30 February 2020). A one-stage robust error meta-regression model based on inverse variance weighted least squares regression and cluster robust error variances was used for the dose–response analysis between Mg supplementation and duration of intervention and glycaemic control factors. Eighteen eligible randomised clinical trials were included in our final analysis. The dose–response testing indicated that the estimated mean difference in HbA1c at 500 mg/d was −0·73 % (95 % CI: −1·25, −0·22) suggesting modest improvement in HbA1c with strong evidence (P value: 0·004). And in fasting blood sugar (FBS) at 360 mg/d was −7·11 mg/dl (95 % CI: −14·03, −0·19) suggesting minimal amelioration in FBS with weak evidence (P value: 0·092) against the model hypothesis at this sample size. The estimated mean difference in FBS and HbA1c at 24 weeks was −15·58 mg/dl (95 % CI: −24·67, −6·49) and −0·48 (95 % CI: −0·77, −0·19), respectively, suggesting modest improvement in FBS (P value: 0·034) and HbA1c (P value: 0·001) with strong evidence against the model hypothesis at this sample size. Oral Mg supplementation could have an effect on glycaemic control in T2DM patients. However, the clinical trials so far are not sufficient to make guidelines for clinical practice.

Knowledge about metabolisable energy (ME) intake is crucial for various experimental settings in rodent studies. ME considers faecal and renal energy losses. In particular, faecal energy excretion can vary considerably between differentially composed diets. Thus determination of faecal energy losses, i.e. apparent energy digestibility, is the most important experimental approach to determine ME. Predictive equations for ME such as Atwater factors or an equation for pigs, which are frequently employed for rodent feed, consider an average energy digestibility for nutrients and average renal losses for protein. Both equations, however, were never validated for rat feed. We therefore determined experimentally the digestibility of energy (experimentally determined digestible energy − 5·2 kJ/g digestible protein) and nutrients of eleven natural and five purified rat diets and compared the present results with the predicted values. Compared with natural diets, digestibility of gross energy (GE) and nutrients was higher by about 20 % in the purified diets (P < 0·0001). Mean GE digestibility in natural diets amounted to 71·4 % (range 53·3–83·5 %; n 11). Atwater factors predicted ME with satisfactory accuracy in purified diets. In contrast, for natural diets, only the equation for pig feed gave acceptable estimates of ME. Choosing an inappropriate predictive equation for ME resulted in considerable error. For prediction of ME in mixed rat feed, we propose to use the equation for pig feed for natural diets and Atwater factors for purified diets. If the equation for pig feed cannot be applied we suggest using the lower modified Atwater factors instead of the ‘original’ Atwater factors to estimate the ME of a diet.

We recently characterised Sprouty1 (Spry1), a growth factor signalling inhibitor as a regulator of marrow progenitor cells promoting osteoblast differentiation at the expense of adipocytes. Adipose tissue-specific Spry1 expression in mice resulted in increased bone mass and reduced body fat, while conditional knockout of Spry1 had the opposite effect with decreased bone mass and increased body fat. Because Spry1 suppresses normal fat development, we tested the hypothesis that Spry1 expression prevents high-fat diet-induced obesity, bone loss and associated lipid abnormalities, and demonstrate that Spry1 has a long-term protective effect on mice fed a high-energy diet. We studied diet-induced obesity in mice with fatty acid binding promoter-driven expression or conditional knockout of Spry1 in adipocytes. Phenotyping was performed by whole-body dual-energy X-ray absorptiometry, microCT, histology and blood analysis. In conditional Spry1-null mice, a high-fat diet increased body fat by 40 %, impaired glucose regulation and led to liver steatosis. However, overexpression of Spry1 led to 35 % (P < 0·05) lower body fat, reduced bone loss and normal metabolic function compared with single transgenics. This protective phenotype was associated with decreased circulating insulin (70 %) and leptin (54 %; P < 0·005) compared with controls on a high-fat diet. Additionally, Spry1 expression decreased adipose tissue inflammation by 45 %. We show that conditional Spry1 expression in adipose tissue protects against high-fat diet-induced obesity and associated bone loss.

1. The biological evaluation of solvent and prepress-solvent processed rapeseed meals RM(S) and RM(PS) was carried out with the weanling (phase 1) and the mature (phase 2) rat. The nutritional indices measured were compared with those for diets containing soyabean meal SM and casein CS.

2. The true nitrogen digestibility (td(N)) for RM(S), RM(PS), SM and CS in the weanling rat was (%) 78.9 f±1.2, 77.9±2.7, 90.4±0.9 and 96.0±0.6 (P < 0.01) respectively. Net protein utilization was (%) 68.9±10.1, 65.6±3.5, 80.6±4.8 and 81.7±3.1 (P < 0.05) respectively. Biological value was (%) 83.0±7.9, 84.1±5.6, 8.90±5.1 and 85.0±3.4 (P < 0.05) respectively. The same indices when measured in the mature rat showed an increase over those obtained in the weanling rat.

3. The growth-promoting effects of the test diets were evaluated over a period of 8 weeks with ad lib. feeding between phases 1 and 2. Protein efficiency ratio averaged 2.0±0.14, 1.9±0.35, 2.4±0.39 and 2.3±0.25 for the RM(S), RM(PS), SM and CS treatments respectively.

4. The daily endogenous urinary N excretion was 1.58±0.14 mg N/basal kcal or 254 mg N/kg body-weight for the weanling rat and 0.16 mg N/basal kcal or 18 mg N/kg body-weight for the mature rat. Metabolic faecal N excretion was 98.0±9.3 mg N/kg body-weight, or 27.9% of the total N output for the weanling rat, and 37.9±7.2 mg N/kg body-weight, or 67.3% of the total N output for the mature rat during the ‘protein-free’ feeding periods.

5. The fresh weight of the thyroid gland per kg metabolic body size was 70, 90, 40 and 40 mg respectively for the RM(S), RM(PS), SM and CS dietary treatments.

6. The moisture content of the carcasses was 66.9±3.1, 63.6±2.3 and 64.2±2.2 and the protein content on a dry-matter basis was 55.9±9.6, 50.2±6.4 and 53.1±4.9 for the RM (S and PS), SM and CS diets respectively. The results suggest an increased lean body mass in the rats receiving the rapeseed meal treatments.

7. Under the conditions of this experiment solvent-extracted rapeseed meal was superior to prepress-solvent meal on the basis of rat growth response and of results for nutritional indices. Both rapeseed meals were inferior to soya-bean meal and casein.

Uniformly 14C-labelled primary cell walls (14C-PCW) were purified from suspension-cultured cells of spinach (Spinacia oleracea L.) grown in a medium containing D-[U-14C]glucose. The approximate polymer composition of the 14C-PCW preparation (% total 14C) was homogalacturonan 30,rhamnogalacturonan 23, xyloglucan 10, other hemicelluloses 3, cellulose 21, lignin 0,14C-labelled protein < 3 and [14C]starch < 2. The degree of methyl esterification of the pectic polysaccharides was about 25%. The 14C-PCW contained about 4% O-acetyl and 3% non-volatile ester-linked residues. When tracer levels of these 14C-PCW were fed to rats, only about 18% of the 14C appeared in the faeces;negligible levels of 14C (0.07%) remained in the gut contents 4 d after feeding. Some 14C was present in the carcass. The results show that U-14C-labelled primary cell walls can be purified and radiochemically analysed by the methods developed here, and that primary cell walls are extensively fermented by the gut microflora of the rat.

The net absorption of amino acids (AA) in young pigs fed a barley-based control diet (C) and diets where barley was replaced by 200 g/kg fresh weight of dried lucerne (Medicago sativa; L20), white clover (Trifolium repens; W20) or perennial ryegrass (Lolium perenne; PR20) meal was studied. Castrated male pigs were fitted with permanent catheters in the hepatic portal vein and mesenteric artery, and the hepatic portal net absorption of AA was estimated from the porto–arterial plasma concentration differences and the hepatic portal-vein blood flow. In general, the essential AA (EAA) concentrations in the hepatic portal vein reached peak levels 90 min after feeding and thereafter exhibited a transient decline. Maximum porto–arterial differences were reached between 1 and 3 h postprandially for most of the AA. The cumulative net absorption of non-essential AA (NEAA) and EAA did not differ significantly between the barley-based diet and diets W20 and PR20. Due to a lower intake of AA on diet L20, the cumulative net absorption of NEAA and EAA was significantly (P<0·05) lower than diet C. With the exceptions of the EAA arginine, cystine and valine, and the NEAA glutamic acid + glutamine and glycine, there were no significant differences in the absorption coefficients for the EAA and NEAA between the diets. In addition, the pattern of the total EAA in the mixture absorbed postprandially did not differ significantly between the diets. The present study gives support to the contention that the replacement of barley AA with forage meal AA in a barley-based diet for growing pigs should be expected to result in minor differences in the net portal flux of AA.

1. Details are given for the construction and use of an apparatus for the incubation of rumen liquor in semi-permeable sacs inside the bovine rumen. It was found practicable, using one animal, to incubate simultaneously samples of strained diluted rumen liquor in three identical vessels, each of 100–120 ml capacity, for periods of up to 23 h.

2. The optimal conditions for experiments of this type were investigated. It was shown that, under the conditions used, the pH value of the reaction mixtures varied little compared with the pH changes that occurred inside the rumen, and that the sampling technique was satisfactory.

3. The effects of the size and type of inoculum were also investigated. The microbial growth, measured by increases in turbidity and in concentration of protein, was greatest when the rumen liquor inoculum constituted about 20% of the reaction mixture and when the protozoa and large food particles were removed.

4. The apparatus was used to study microbial growth and hydrogenation of fatty acids in rumen liquor.

Riboflavin deficiency interferes with the growth and multiplication of malaria parasites as well as the host response to malaria. The objective of the present work was to determine the effects of riboflavin deficiency on erythrocyte glutathione peroxidase (EC 1.11.1.9; GPx) and superoxide dismutase (EC 1.15.1.1; SOD) in rats infected with Plasmodium berghei malaria. Riboflavin in its co-enzyme form, FAD, is required by glutathione reductase (EC 1.6.4.1) to regenerate GSH and GSH is an important cellular antioxidant both in its own right and also as a substrate for the enzyme GPx. Weanling rats were deprived of riboflavin for 8 weeks before intraperitoneal injection of 1 × 106P. berghei parasites. Control animals were weight-matched to the respective riboflavin-deficient group. At 10d post-infection, parasite counts were higher in the weight-matched control group than the riboflavin-deficient group (P = 0.004). GPx activity was higher in erythrocytes of rats parasitized with P. berghei than comparable non-infected rats regardless of riboflavin status (P < 0.05). As mature erythrocytes do not synthesize new protein, the higher GPx activities were probably due to the presence of the parasite protein. In erythrocytes from riboflavin-deficient rats, GPx activity tended to be lower than in those rats fed on diets adequate in riboflavin (weight-matched controls) whether parasitized or not, but the difference was not significant. Neither riboflavin deficiency nor malaria had any effect on erythrocyte SOD activity. It was concluded that riboflavin deficiency has no marked effect on erythrocyte GPx or SOD activity in the rat.

1. Rhode Island Red and Light Sussex poultry attained their full size in about 6 months.

2. When they were held back by undernutrition so that they weighed only about 170g at 6 months of age and were then given unlimited food, they grew—like the normal birds—for about 6 months, i.e. till they were 1 year old, but still they did not attain the same stature as normal birds. 3. The pullets more nearly attained the size of their controls than did the cockerels. 4. On rehabilitation after the period of undernutrition poultry frequently suffered leg weakness which in its extreme form could be diagnosed as perosis. 5. Rehabilitated pullets began to lay large eggs after a comparatively short period of growth and when they were still a small size.

The WHO has called for governments to improve children’s food environment by implementing restrictions on the marketing of ‘unhealthy’ foods to children. Nutrient profiling (NP) models are used to define ‘unhealthy’ foods and support child-directed food marketing regulations. The aim of the present study was to assess the suitability of the South African NP model (SANPM), developed and validated for health claim regulations, for child-directed food marketing regulations. The SANPM was compared with four NP models specifically developed for such regulations. A representative list of 197 foods was compiled by including all foods advertised on South African free-to-air television channels in 2014 and foods commonly consumed by South African children. The nutritional information of the foods was sourced from food packaging, company websites and a food composition table. Each individual food was classified by each of the five NP models. The percentage of foods that would be allowed according to the different NP models ranged from 6 to 45 %; the models also varied considerably with regard to the type of foods allowed for marketing to children. The majority of the pairwise comparisons between the NP models yielded κ statistics >0·4, indicating a moderate agreement between the models. An almost perfect pairwise agreement (κ=0·948) existed between the SANPM and the UK Food Standards Agency model (United Kingdom Office of Communication nutrient profiling model), a model extensively tested and validated for such regulations. The SANPM is considered appropriate for child-directed food marketing regulations in South Africa.

Poor early nutrition may elicit long-term detrimental effects on adult health, including susceptibility to non-insulin-dependent diabetes mellitus. We investigated the impact of moderate maternal protein restriction during pregnancy and lactation on the action of insulin on adipocyte glucose uptake in female offspring during their own pregnancies. Offspring of dams provided with diets containing either 200 g protein/kg or 80 g protein/kg during pregnancy and lactation (termed C and EPR groups respectively) were weaned on to 200 g protein/kg diet at 24 d of age. At 9–12 weeks of age both groups were time-mated and studied at day 19 of gestation. Rates of glucose utilization (assessed using the 2-deoxy-d-- [1-3H- ]glucose technique) measured in five distinct adipose tissue depots (parametrial (PM), mesenteric (MES), perirenal (PR), subcutaneous (SC), interscapular (IS)) in vivo in the post-absorptive state were consistently lower in early-protein-restricted (EPR) pregnant rats compared with control (C) pregnant rats. In C pregnant rats, insulin significantly increased glucose utilization only in the IS depot. In contrast, significantly increased glucose utilization rates in response to hyperinsulinaemia were evident in all five adipose-tissue depots of the EPR pregnant group. Consequently, glucose utilization rates in PM and SC depots during hyperinsulinaemia were significantly higher in EPR pregnant rats compared with C pregnant rats. Adipocytes were isolated from PM and MES depots to determine whether altered responses to insulin in vivo were retained in vitro. Rates of insulin-stimulated glucose uptake at sub-maximal (15 μU/ml) and maximal (15 mU/ml) insulin concentrations were significantly higher in both MES and PM adipocytes from EPR pregnant rats, but the sensitivity of glucose uptake to insulin at low concentrations was blunted compared with adipocytes from C pregnant rats. The results demonstrate that early protein restriction enhances the capacity for adipocyte glucose uptake at high insulin concentrations, but dampens the response to insulin at low physiological concentrations.

Accumulation of homocysteine and S-adenosylhomocysteine in bone has been shown to be associated with reduced bone quality in rats. The aim of the present study was to investigate whether high bone concentrations of homocysteine and S-adenosylhomocysteine as well as a low methylation capacity are related to an impaired bone morphology in humans. Concentrations of homocysteine and its precursors S-adenosylhomocysteine and S-adenosylmethionine were measured in femoral bone samples of eighty-two males and females (age 71 (sd 8) years) who underwent elective hip arthroplasty. Cancellous bone structure was analysed by histomorphometry. In addition, blood was sampled to measure serum concentrations of homocysteine. Results of bone and serum analyses were grouped for individuals with high or low bone concentrations of homocysteine, S-adenosylhomocysteine and S-adenosylmethionine, as well as for individuals with a high or a low methylation capacity, which is indicated by a low or a high S-adenosylhomocysteine:S-adenosylmethionine ratio (n 41, each). Histomorphometry showed a higher trabecular separation and a lower trabecular thickness, trabecular number and trabecular area in individuals with high bone concentrations of homocysteine and S-adenosylhomocysteine compared with individuals with low bone concentrations of homocysteine and S-adenosylhomocysteine. There was no association between the S-adenosylhomocysteine:S-adenosylmethionine ratio and bone morphology. It was found that 48 % of bone homocysteine was bound to the collagen of the extracellular bone matrix. Blood analyses demonstrated a significant correlation between serum and bone homocysteine. The results of the present study indicate an association between altered bone morphology and elevated bone concentrations of homocysteine and S-adenosylhomocysteine, but not between altered bone morphology and methylation capacity.