Ileal digestibility of amino acids of cassava, sweet potato, cocoyam and erythrina foliages fed to growing pigs

Dietary intake of sulfur amino acids and risk of kwashiorkor malnutrition in eastern Democratic Republic of the Congo

BACKGROUND

Kwashiorkor is an often-fatal type of severe acute malnutrition affecting hundreds of thousands of children annually, but whose etiology is still unknown. Evidence suggests inadequate sulfur amino acid (SAA) status may explain many signs of the condition but studies evaluating dietary protein intake in relation to the genesis of kwashiorkor have been conflicting. We know of no studies of kwashiorkor that have measured dietary SAAs.

OBJECTIVES

We aimed to determine whether children in a population previously determined to have high prevalence of kwashiorkor [high-prevalence population (HPP)] have lower dietary intakes of SAAs than children in a low-prevalence population (LPP).

METHODS

A cross-sectional census survey design of 358 children compared 2 previously identified adjacent populations of children 36-59 mo old in North Kivu Province of the Democratic Republic of the Congo. Data collected included urinary thiocyanate (SCN), cyanogens in cassava-based food products, recent history of illness, and a 24-h quantitative diet recall for the child.

RESULTS

The HPP and LPP had kwashiorkor prevalence of 4.5% and 1.7%, respectively. A total of 170 children from 141 households in the LPP and 169 children from 138 households in the HPP completed the study. A higher proportion of HPP children had measurable urinary SCN (44.8% compared with 29.4%, P < 0.01). LPP children were less likely to have been ill recently (26.8% compared with 13.6%, P < 0.01). Median [IQR] intake of SAAs was 32.4 [22.9-49.3] mg/kg for the LPP and 29.6 [18.1-44.3] mg/kg for the HPP (P < 0.05). Methionine was the first limiting amino acid in both populations, with the highest risk of inadequate intake found among HPP children (35.1% compared with 23.6%, P < 0.05).

CONCLUSIONS

Children in a population with a higher prevalence of kwashiorkor have lower dietary intake of SAAs than children in a population with a lower prevalence. Trial interventions to reduce incidence of kwashiorkor should consider increasing SAA intake, paying particular attention to methionine.

Sweet potato vines in diets for growing rabbits on performance, carcass characteristics and meat quality

The use of residues as substitutes for conventional ingredients in animal feed is a promising alternative able to reduce both costs and environmental pollution. This study aimed to evaluate the viability of using sweet potato vines (SPV) as a replacement for alfalfa hay in diets for growing rabbits. The performance, carcass characteristics, meat composition and metabolic parameters of the liver were evaluated in 30 New Zealand rabbits weaned at 35 days old and an average weight of 900 g. The animals were allotted into three dietary groups: 0SPV, control diet without SPV; 50SPV, diet with 50% replacement of alfalfa hay by SPV; 100SPV, diet with 100% replacement of alfalfa hay by SPV. The animals were slaughtered at 77 days of age. The liver was collected for analysis of glucose and hepatic glycogen and meat samples were collected for analysis of the chemical composition. The data obtained were statistically compared by analysis of variance followed by the Tukey test (0.05). None of the analyzed variables presented differences. It can be concluded, therefore, that SPV may be used as a substitute for alfalfa hay up to 100% in diets for rabbits without impairing the performance and meat composition.

Effect of sweet potato vines on performance parameters and some carcass characteristics of rabbits

Conventional feedstuffs in Brazil are expensive, which has led to the search for less conventional cheaper and locally available feedstuffs. Thus, this study was carried out to determine the dietary effect of dry sweet potato vines (SPV) on the performance and some carcass characteristics of rabbits. A total of twenty-seven weaned White New Zealand rabbits (14 male and 13 female) 35 days old with an average initial weight of 755 g were allocated into three treatments. Nine rabbits were assigned to each treatment in a completely randomized design. Three diets were formulated to similar protein and energy levels: 0SPV - diet without inclusion of dry sweet potato vines; 10SPV - diet with 10% alfalfa hay replaced by dry sweet potato vines; and 15SPV - diet with 15% of alfalfa hay replaced by dry sweet potato vines. The experiment lasted for 49 days during which data for feed intake and body weight were recorded. The daily feed intake ranged from 73.17 to 78.02 g; daily weight gain from 22.32 to 23.17 g; feed conversion ratio (FCR) from 3.16 to 3.49 and final live weight ranged from 1839.44 to 1880.55 g. None of the evaluated performance parameters as well as carcass weight, heart weight and percentages of fat and protein in meat were significantly affected by any of the tested dietary treatments. However, the liver weight was statistically lower in animals fed the diets containing 10% of SPV, mainly due to lower glucose content. Glycogen within the tissue, did not differ significantly among treatments. It was therefore concluded that up to 15% of SPV can successfully be included in the diet of rabbits as a cheaper replacement for alfalfa hay without adversely affecting performance.

Forage plants as an alternative feed resource for sustainable pig production in the tropics: a review

Globally, pressure on concentrate feed resources is increasing, especially in the tropics where many countries are net importers of food. Forage plants are a possible alternative, but their use as feed ingredients for pigs raises several issues related to their higher fibre and plant secondary metabolites contents as well as their lower nutritive value. In this paper, the nutritive value of several forage species and the parameters that influence this nutritive value in relationship to the plant family, the physiological stage, the plant part and the preservation method (fresh, hay and silage) are reviewed. The influence of the breed and the physiological status of the animal on animal voluntary intake of fibre-rich ingredients, digestibility as related to gastrointestinal volume and transit time and growth performances are also discussed. The final section highlights the advantages and drawbacks of forage plants in pig diets and stresses the need for proper economic evaluation to conclude on the benefits of the use of forage plants in pig feed.