Eliton Chivandi

Fat absorption and deposition in Japanese quail (Coturnix coturnix japonica) fed a high fat diet

Dietary fat contributes significantly to the energy requirements of poultry. Not all species are able to increase their absorptive capacity for fats in response to a high fat diet. The effects of a high fat diet (10% canola oil) on the lipid absorption and deposition in the liver, breast and thigh muscles of male and female Japanese quail were investigated. Thirty-eight Japanese quail (Coturnix coturnix japonica) were randomly divided into a high fat diet (HFD) and a standard diet (STD) group. The birds were fed the diets for seven weeks after which half of the birds were subjected to oral fat loading tests (OFLT) with plant oils containing long-chain and medium-chain triglycerides. The remaining birds were included for the lipid deposition measurements. Thereafter the birds were euthanised, blood samples were collected and liver, breast and thigh muscle lipid deposition was determined. Female quail on both diets had significantly higher plasma triglyceride concentrations (p < 0.05) compared with their male counterparts. No significant differences in plasma triglyceride concentrations were observed after the OFLTs. Female quail had significantly heavier liver masses compared with the males but there was no significant difference in the liver lipid content per gram liver mass. Female quail on the HFD had higher lipid content (p < 0.05) in the breast muscle compared with their male counterparts whilst male quail on the HFD had higher lipid content (p < 0.05) in the thigh muscle in comparison with both males and females on the standard diet. Dietary supplementation with 10% canola oil did not alter gastrointestinal tract lipid absorption, but it caused differences between the sexes in muscle lipid accumulation, the physiological significance of which requires further investigation.

Use of Essential Oils as a Preservative of Meat

Abstract Historically the preservation of meat included use of the sun for drying of meat, smoking, and pickling. Currently, refrigeration and synthetic chemical preservatives are also used. Synthetic chemical preservatives have been implicated in the increased incidence of diseases such as cancer in consumers. Synthetic preservatives have a negative effect on the environment. Natural products, especially essential oils (EOs), are being targeted as potential meat preservatives due to their antimicrobial potential and their added beneficial effects on consumer health and the environment. EOs add to the nutritional value of the meat, and have antioxidant and anticancer properties. Large-scale use of EOs as meat preservatives should be preceded by more research around issues of allergies, product quality, and effective concentrations.

Potential Usage of African Ebony (Diospyros mespiliformis) Seeds in Human Health

Publisher Summary This chapter profiles the potential usage of Diospyros mespiliformis (DSM) fruit seeds in human nutrition and health. Research on the potential uses of DSM has focused largely on the ethno-medical potential of the trees leaf, bark, and root extracts. The bark, root, and leaf extracts are widely employed in ethno-medicine. A leaf decoction is reportedly used in the treatment of malaria and headaches, and as an anthelmintic. The bark extract reportedly provides good relief for coughing. Extracts from the plant have also been shown to have analgesic and antipyretic effects. DSM fruit pulp largely consists of carbohydrates; it has little protein but contains appreciable amounts of minerals as well as vitamin C. It also has low concentrations of oxalate, phytate, saponin, and tannin. As a human food resource, the soluble sugars and starch make DSM seeds a potential source of dietary energy. In drought years when conventional crops fail to thrive, the highly energy-dense seeds could be used to replace calories that would otherwise be derived from cereal grain. There is a need to fully characterize the anti-nutritional factor content of Diospyros mespiliformis seed and breed plant varieties with higher seed oil yields but maintaining the current fatty acid profile.

The response of male and female rats to a high-fructose diet during adolescence following early administration of Hibiscus sabdariffa aqueous calyx extracts

Metabolic syndrome is linked to the consumption of fructose-rich diets. Nutritional and pharmacological interventions perinatally can cause epigenetic changes that programme an individual to predispose or protect them from the development of metabolic diseases later. Hibiscus sabdariffa (HS) reportedly has anti-obesity and hypocholesterolaemic properties in adults. We investigated the impact of neonatal intake of HS on the programming of metabolism by fructose. A total of 85 4-day-old Sprague Dawley rats were divided randomly into three groups. The control group (n=27, 12 males, 15 females) received distilled water at 10 ml/kg body weight. The other groups received either 50 mg/kg (n=30, 13 males, 17 females) or 500 mg/kg (n=28, 11 males, 17 females) of an HS aqueous calyx extract orally till postnatal day (PND) 14. There was no intervention from PND 14 to PND 21 when the pups were weaned. The rats in each group were then divided into two groups; one continued on a normal diet and the other received fructose (20% w/v) in their drinking water for 30 days. The female rats that were administered with HS aqueous calyx extract as neonates were protected against fructose-induced hypertriglyceridaemia and increased liver lipid deposition. The early administration of HS resulted in a significant (P⩽0.05) increase in plasma cholesterol concentrations with or without a secondary fructose insult. In males, HS prevented the development of fructose-induced hypercholesterolaemia. The potential beneficial and detrimental effects of neonatal HS administration on the programming of metabolism in rats need to be considered in the long-term well-being of children.

A comparison of the proximate, fibre, mineral content, amino acid and the fatty acid profile of Marula (Sclerocarya birrea caffra) nut and soyabean (Glycine max) meals

BACKGROUND As a result of shortages and the cost of the currently utilized conventional dietary protein sources in the Sub-Saharan Africa feed industry, the chemical evaluation of available non-conventional sources for feed is imperative. One such source is Marula nut meal (a by-product of Marula oil extraction). The present study chemically characterized the nutritional composition of two differently processed Marula nut meals (MNMs) and compared them with that of solvent extracted soyabean meal (SBM). RESULTS The MNMs had higher dry matter, ether extract and gross energy but lower crude protein and ash contents compared to SBM. The cold press produced Marula nut meal (MNM2) had higher arginine than the hydraulic filter press produced Marula nut meal (MNM1) and SBM. The meals had similar neutral and acid detergent fibre contents. The MNMs had higher phosphorus, magnesium and copper concentrations than SBM. Although the total saturated fatty acid proportion was similar across the meals, total monounsaturated and polyunsaturated fatty acid proportions were higher in MNMs and SBM, respectively. Oleic acid was higher in MNMs than in SBM. CONCLUSION The low crude protein content in MNMs compared to SBM is comparable with other conventional dietary protein sources. Thus, the MNMs could be used as protein and energy feed ingredients.

Insulinotropic Effect of S-Allyl Cysteine in Rat Pups

S-Allyl cysteine (SAC) is found in garlic and has been reported to exert antidiabetic and antiobesity properties in drug-induced adult experimental models of metabolic dysfunction, but its potential beneficial effects in high-fructose diet neonatal rat models have not been determined. This study investigated the potential prophylactic effects of SAC in high-fructose diet fed suckling rat pups modelling human neonates fed a high-fructose diet. Four-day-old male (n=32) and female (n=32) Wistar rat pups, were randomly assigned to and administered the following treatment regimens daily for 15 days: group I, distilled water; group II, 20% fructose solution (FS); group III, SAC; group IV, SAC+FS. The pups’ blood glucose, triglyceride, cholesterol, plasma leptin and insulin concentration, liver lipid content, and liver histology were determined at termination. In female rat pups, orally administered SAC prevented FS-induced hypoinsulinemia but significantly increased (P≤0.05) liver lipid content. Oral administration of SAC significantly increased (P≤0.05) plasma insulin concentration and homeostasis model assessment for insulin resistance in the male pups. The potential sexually dimorphic effects of SAC (insulinotropic effects in male pups and protection of female pups against fructose-induced hypoinsulinemia) suggest that SAC could be potentially exploited as an antidiabetic and insulinotropic agent. Caution should, however, be exercised in the use of SAC during suckling as it could result in excessive liver lipid accumulation and insulin resistance.

Nitrogen leakages and vegetable dry matter yield in a subtropical wetland soil amended with cattle manure and mineral nitrogen fertiliser

The response of nitrous oxide emission and nitrate leaching to increased nitrogen (N) fertiliser and cattle manure applications to wetland vegetable cropping in subtropical Africa have significant impacts on the atmospheric and terrestrial environments. Two field experiments were carried out in a wetland in central Zimbabwe in order to determine the effects of N fertiliser and cattle manure applications on emissions of N2O, nitrate leaching and dry matter yield of rape and tomato. The static chamber and gas chromatography techniques were used to capture and measure fluxes of N2O. A station of buried lysimeters was employed to collect leachate for determining nitrate leaching losses. The experiments were in completely randomised block designs. The loss of N in nitrate leaching increased significantly with increasing rates of manure and mineral fertiliser applications. When the application rates of N fertiliser and manure were increased, the emissions of N2O per unit harvested dry matter yield significantly decreased. Losses of N in N2O emissions can be reduced by adopting agronomic practices that enhance N uptake and higher dry matter yield. The loss of N from applied fertilisers in nitrate leaching was 6–20 times greater than the loss of N in N2O emissions in wetland vegetable production.