Forty-two crossbred lambs (33·4 kg initial body weight; twenty-four wethers and eighteen ewes) were used in a 42 d experiment with a 2 × 3 factorial treatment arrangement to determine effects of forage level and source on splanchnic tissue mass. Diets were 250 and 750 g/kg of chopped lucerne (Medicago sativa) (A), ryegrass (Lolium multiflorum)–wheat (Triticum aestivum) (RW) or bermudagrass (Cynodon dactylon) (B) hay, with the remainder being maize-based concentrate. Five lambs per treatment were slaughtered at the end of the experiment and measurements made of internal organs and contents of the gastrointestinal tract (GIT). Digestible organic matter intake (DOMI) on the 7 d preceding slaughter was 0·89, 0·83, 0·90, 0·83, 0·77 and 0·61 (SE 0·05) kg/d, and live-weight gain was 0·20, 0·17, 0·18, 0·10, 0·10 and 0·07 (SE 0·02) kg/d for diets A-25, RW-25, B-25, A-75, RW-75 and B-75 respectively. Total GIT mass (fresh) was higher (P < 0·05) for 750 than 250 g forage/kg and for B than RW (4·80, 4·57, 5·55, 5·84, 5·99 and 6·91 kg for diets A-25, RW-25, B-25, A-75, RW-75 and B-75 respectively). Nonfat organic matter was 259, 295, 292, 303, 277 and 264 g for the total GIT; 93, 102, 103, 106, 95 and 97 g for the reticulo-rumen (forage level × type (diet A v. diets RW and B) interaction; P < 0·05); and 204, 196, 202, 177, 156 and 127 g for the liver (SE 10) with diets A-25, RW-25, B-25, A-75, RW-75 and B-75 respectively. In summary, differences in properties of forage A and the grasses at 250 g/kg diet may have influenced GIT mass independent of energy intake and digesta mass. Conversely, with 750 g dietary forage/kg, higher digesta mass for diet B than diet RW appeared responsible for high reticulo-rumen mass relative to DOMI. Greater digesta mass for 750 than 250 g forage/kg may have elevated intestinal tissue mass/DOMI with diets A and B but not with diet RW, for which NDF digestibility was highest.

The effects of changing rumen osmotic pressure (OP) upon water kinetics and volatile fatty acid (VFA) absorption in the rumen of sheep were studied in two 4 × 4 Latin square experiments, each using four lambs with a rumen cannula and an abomasal catheter. In both experiments the lambs were sustained by the intragastric infusion of all nutrients (VFA, Ca, P, Mg and a buffer solution into the rumen, and casein, vitamins and trace elements into the abomasum). On experimental days, which were at least 1 week apart, drinking water and the casein infusion were withdrawn, and the ruminal OP was changed and held constant for 9·5 h, by incorporating NaCl at different concentrations in the buffer solution being infused. In Expt 1 the target OP values were 300, 340, 380 and 420 mosmol/kg, and in Expt 2 were 261 (no saline addition), 350, 420 and 490 mosmol/kg. Using soluble non-absorbable markers (PEG in continuous infusion and Cr-EDTA injected in pulse doses) rumen volume, liquid outflow rates, apparent water absorption through the rumen wall and VFA absorption rates were estimated at six sampling times corresponding to the 1·5 h intervals during the last 7·5 h following the change in rumen OP. Liquid outflow rate (F; ml/h) showed a significant and positive linear relationship with the rumen OP (mosmol/kg), resulting in the equation F = 1·24 OP (SE 0·096)–36·5 (SE 36·6) (r2 0·96). Similarly, water absorption rate (W; ml/h) was significantly affected by rumen OP, and this relationship was given by W = 395 (SE 39·9) −1·16 OP (SE 0·105) (r2 0·95), which means that for an OP of 341 mosmol/kg the net movement of water across the rumen wall would be zero, and either a net efflux or a net influx of water would be observed with lower or higher OP respectively. In Expt 2 there was a significant linear effect of OP on rumen volume (P <0·01), with higher OP being associated with increases in rumen liquid contents of about 10–20%. As rumen OP was increased there was also a decline in the absorption rate of VFA (from 232 mmol VFA/h for OP 350 to 191 mmol/h for OP 490 mosmol/kg), resulting in the accumulation of VFA (especially acetate) in the rumen and a consequent fall in rumen pH. Rumen OP seems to be important in defining water movement across the rumen wall and, hence, partitioning between absorption and outflow.

The present study focuses on the digestion and absorption of milk and fermented milk (FM) reflected by gastro-ileal N and electrolyte movements in six healthy volunteers. The N and electrolyte content of the intestinal effluents were analysed both at the beginning of the jejunum and in the distal ileum. The gastric half-emptying time of the liquid phase was significantly (P < 0·05) shorter for milk (35 (SE 2) min) than for FM (60 (SE 2) min). The N balance showed that 58 and 50 % of ingested proteins, milk and FM respectively were absorbed between the stomach and the proximal jejunum and that 91 and 90% respectively were absorbed between the stomach and the terminal ileum in 240 min. Evaluation of mineral absorption indicated that 44 and 67% of Ca was absorbed in the duodenum after milk and FM ingestion respectively, and 41 and 11% of Ca disappeared between the jejunum and the ileum respectively. With regards to N and Ca intestinal availability, the present study confirms that FM products represent an interesting source of N as well as minerals for man. This confers on FM a beneficial effect compared with milk especially for lactase (EC 3.2.1. 108)–deficient subjects and children with persistent diarrhoea.

Pectin is known as a cholesterol-reducing dietary fibre, and in the present study we addressed the question whether pectin affected the quantity of lipid in droplets in the myocardial cells and of lipid in the liver cells. Male Wistar rats received either a diet containing cholesterol or a standard diet without cholesterol with 0, 50 or 100 g pectin/kg incorporated for 10 d. The fractional volume of lipid droplets in the myocardial cells decreased as a function of pectin dose in both the standard-fed and the cholesterol-fed rats. Serum cholesterol was significantly reduced in both groups after addition of 100 g pectin/kg diet. The cholesterol diet increased the liver cholesterol level, and 100 g pectin/kg diet resulted in a lower concentration of liver cholesterol in the cholesterol-fed animals, but the influence on standard-fed rats was modest. Hydroxymethylglutaryl-CoA reductase (EC 1.1.1.88; HMG-CoA reductase) activity-increased when pectin was given in the standard diet. Liver triacylglycerol level increased after cholesterol and pectin feeding. Mitochondrial fatty acid oxidation and phosphatidate phosphohydrolase (EC 3.1.3.4) activity tended to decrease, whereas the peroxisomal fatty acid oxidation and acyl-CoA oxidase activity were unchanged. Increased hepatic triacylglycerol content by cholesterol and pectin treatment may be due to inhibited mitochondrial fatty acid oxidation along with increased availability of fatty acid for esterification and triacylglycerol synthesis. The presence of pectin in the diets of cholesterol-fed rats resulted in increased hepatic concentration of triacylglycerols and increased mitochondrial fatty acid oxidation. In this case the hepatic accumulation of triacylglycerol may be mediated by a reduced efflux of triacylglycerols from the liver.

A correlation between dietary lipids and cellular enzyme activities is a problem that has only been partially addressed by nutritionists. Therefore, changes in the fatty acid composition and the activities of some key metabolic enzymes (ubiquinol-2-cytochrome c reductase (EC 1.10.2.2), cytochrome oxidase (EC 1.9.3.1) and ATPase (EC 3.6.1.3)) in the mitochondria of liver, heart and brain of rats fed on diets differing extensively in their polyunsaturated fatty acid compositions have been investigated. The results showed that fatty acid compositional changes brought about by the dietary differences were associated with extensive changes in the activities of these key enzymes in the mitochondria. The extent of the influence differed considerably with the period over which the diets were fed. The role of dietary lipids to effect changes through the preservation of membrane structural integrity is discussed.

The absorption of 59Fe from preparations of FeSO4 and the ferric hydroxypyranone complexes maltol and ethyl maltol was studied by whole-body counting in normal subjects and patients with Fe deficiency. Fe in the Fe3+ complexes was in general absorbed almost as well as Fe2+. It is concluded that the absorption of Fe3+ from hydroxypyranone complexes is much greater than that from simple Fe3+ salts; this may prove an efficient and less toxic form of Fe for the treatment of deficiency.

To investigate diurnal changes in large-bowel metabolism rats were fed once daily on a cooked maize-based diet without or with 200 g wLeat bran/kg diet and containing Cr2O3 as an indigestible marker. After 17 d four rats on each diet were killed at 4, 10, 16 and 22 h postfeeding. Emptying of dry matter (DM) from the stomach occurred by an apparently zero-order process at about 0·5 g/h in both diet groups. Feeding wheat bran had little effect on caecal pH or total short-chain fatty acid (SCFA) concentration but was associated with a marked increase in molar proportion of butyrate and a fall in propionate. There were substantial changes in caecal total SCFA concentration and in the molar proportions of individual SCFA throughout the day but no evidence of an interaction between diet and time interval after feeding. Caecal transit time (TT) was significantly reduced by feeding wheat bran whilst colonic TT was unaffected. Although when averaged across both diets there were no significant time effects on caecal or colonic TT, there was a significant diet × time interaction for caecal TT. The extent of coprophagy was measured. The proportion of stomach DM derived from ingested faeces increased with time interval after feeding but it was always a minor contribution so that in these circumstances coprophagy is unlikely to result in significant bias in estimates of digesta flow-rates or TT.

Infants born to atopic parents have been found to be at high risk of allergy development. The present study investigated the effect of a maternal milk-free diet during late pregnancy and lactation on the immune response and allergy incidence in at-risk and control infants. Atopic mothers were randomly allocated into an intervention group (n 12) or an unrestricted-diet group (n 14) and compared with non-atopic mothers following an unrestricted diet (n 12). The intervention involved a maternal milk-free diet during late pregnancy and lactation. Infants were followed up for 18 months postnatally. A significant fall in maternal serum β-Iactoglobulin (β-Lg)–immunoglobulin G (IgG) antibody levels (P < 0.05) was observed after a 7-week milk-exclusion diet. In maternal and cord serum samples the levels of β-Lg–IgG and α-casein–IgG antibodies were significantly correlated (r 0.89, P < 0.0001 and r 0.71, P < 0.001 respectively). Higher levels of β-Lg–IgG (P < 0.05) were observed in the cord serum samples compared with paired maternal serum samples. Single-blind allergy assessment by a paediatrician at 12 and 18 months showed that the infants born in the non-atopic group had a significantly lower allergy incidence compared with the infants born in the atopic group following an unrestricted diet (P < 0.008 and P < 0.02 respectively). The allergy incidence in the infants born in the atopic diet group was significantly lower compared with that of the atopic group following an unrestricted diet (P < 0.04). It was observed that the atopic nature of the parents significantly affected the allergy incidence in their children. A trend towards a beneficial effect of a maternal milk-free diet during late pregnancy and lactation was also observed in infants born to atopic parents.

Thirty-two calves were studied to determine the effects of level of nutrition (400 and 1000 g (air-dry matter) milk substitute per d) and age at weaning (5, 9 and 13 weeks) on humoral immune responses measured in serum and bronchoalveolar washings (BAW). All calves were immunized with Keyhole limpet haemocyanin (KLH) at 3 weeks of age, and with horse erythrocytes (HRBC) 1 d after weaning. Feeding the higher level of nutrition compared with the lower level decreased anti-HRBC titres and serum IgG2 and IgA responses to KLH (P < 0·05). Weaning at 5 compared with 9 weeks of age decreased serum anti-HRBC responses (P < 0·05), but weaning age had no effect on anti-KLH responses (P > 0·5). Feeding the higher level of nutrition increased total protein (P < 005) and IgG2 concentrations (P < 0·01) in BAW. The results showed that variation in husbandry conditions that is within conventional limits affects humoral immune responses in young, artificially-reared calves.

The aim of the study was to investigate whether proposed dietary scores of atherogenicity and thrombogenicity predict ischaemic heart disease (IHD) risk in a community sample of men aged 45–59 years. Dietary scores were calculated from consumption of various fatty acids, estimated from 7 d weighed intake data obtained from 665 men. Investigation of associations with blood lipids, lipoproteins and haemostatic factors revealed positive associations with low-density-lipoprotein cholesterol (P < 0·05) and white cell count (P < 0·05), and a negative association with antithrombin III (P = 0·05), after taking into account the effects of age, body mass index and smoking. During a 5-year follow-up period, there were twenty-one new IHD events among the 512 men in whom there was no evidence of IHD at baseline. Men with higher atherogenicity or thrombogenicity scores at baseline tended to have a higher risk of subsequent IHD. The trend was consistent but not statistically significant. A similar trend was observed for total saturates, and an inverse trend for total polyunsaturates, expressed as a percentage of total fatty acids. It is, therefore, concluded that proposed dietary indices of atherogenicity and thrombogenicity may be weak predictors of IHD risk, but that these scores are unlikely to be substantially better predictors than more simple approaches such as intakes of total saturates. To enhance the predictive ability, more complex formulas which take into account other dietary factors as well as fatty acid intakes would probably be required.

The present study examines the influence of parental history of death from cardiovascular disease on dietary habits and nutritional status of a group of seventy-two Spanish elderly. Those with at least one parent who had died of cardiovascular disease (43·1% of the cases) had higher diastolic blood pressure (P < 0·05) and nutrient intakes less favourable from the cardiovascular risk point of view than those whose parents died of other causes. Descendants whose parents died of cardiovascular disease had higher total fat, animal fat, saturated fatty acids, myristic acid and palmitic acid intakes and a lower monounsaturated fatty acids: saturated fatty acids value than descendants of those who died from other causes (all P < 0·05).

Plasma cholesterol change, or ‘responsiveness’, to dietary saturated fat modification has long been acknowledged. The present study sought to determine the specific, predicted response of each cholesterol subfraction to known dietary manipulations. Two metabolically controlled diets, one with a low polyunsaturated:saturated fat (low P:S) ratio, and one with a high P:S ratio were fed in a crossover design to sixty-seven normolipidaemic subjects pooled from six foregoing metabolic studies. A series of statistical analyses was performed to identify the lipids and subfractions independently affected by the diet crossover. Multivariate analysis of variance revealed that the changes in total cholesterol (ΔTC), low-density-lipoprotein-cholesterol (ΔLDL-C), and high-density-lipoprotein-cholestero! (ΔHDL-C) were the only statistically significant diet-specific‘responsive’lipids. Multiple regression was performed to identify the independent predictors of ΔTC, ΔLDL-C and ΔHDL-C. It was found that age (years), extent of change in dietary saturated fat, and baseline LDL-C (mg/l) levels determine LDL-C change, while extent of change in saturated and polyunsaturated fat, and baseline HDL-C (mg/l) levels can predict HDL-C change. A series of equations to predict lipoprotein responsiveness to diet are derived for potential use in clinical practice.

Walker 256 carcinosarcoma cells (1 × 104) were injected into the right thigh muscle of Sprague–Dawley rats (125 g) consuming isoenergetic (200 g fat/kg) diets containing 20, 100 and 200 g maize oil/kg and 180, 100 or 0 g hydrogenated lard/kg respectively. Ten rats from each dietary regimen were killed every 4th day. Tumours grew rapidly from day 0 to day 8 post-transplant regardless of dietary regimen. However, after 8 d more tumours regressed and there were fewer deaths in animals fed on 200 g maize oil/kg compared with animals fed on 20 or 100 g maize oil/kg. Linoleic acid (LA) levels were higher in phospholipids (PL) of growing tumours than in regressing tumours whereas arachidonic acid levels in PL were lower in growing tumours indicating a possible alteration in the desaturation and elongation of LA. Serum prostaglandin E2 levels were slightly lower in rats with regressing tumours than in rats with growing tumours.

We compared anthropometric indices in samples of elderly people aged 65 years and over living in two French areas. The samples were divided into four age-groups (65–69, 70–74, 75–79 and over 80 years). We observed interregional differences in women aged 65–69 years and in men aged 65–74 years. Weight and anthropometric variables related to body fat percentage and to muscle mass showed a decline with age as already reported by others. We established anthropometric percentile values according to sex in pooled subjects when no integrated difference was found. The 50th percentile of arm circumference, muscle arm circumference and triceps skinfold was higher, and the 50th percentile of body mass index was lower than the one reported for the same indices from an elderly Welsh population. Our results show that an interregional difference in anthropometric indices exists in the elderly. The differences which are observed between our results and those reported from a British population emphasize the importance of establishing local values for the elderly population.