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81.
BACKGROUND: A national survey found that micronutrient deficiencies are prevalent in South African children, particularly calcium, iron, zinc, riboflavin, niacin, vitamin B6, folate, vitamin A, E and C. Mandatory fortification of maize meal and wheat flour were introduced in 2003 to combat some of the deficiencies found in children. To date however, there has not been a national survey on dietary intake in adults. OBJECTIVES: The main objectives of this study were to evaluate the micronutrient intake of the diet consumed by the average adult South African by means of secondary data analyses and secondly to evaluate the effects of fortification on selected nutrient intakes. STUDY DESIGN: Secondary data analysis was carried out with numerous dietary surveys on adults to create a database that included sampling (and weighting) according to ethnic/urban-rural residence in line with the population census, of which 79% were black Africans and the majority resided in rural areas. The effect of fortification was evaluated by substituting fortified foods in the diet for the unfortified products. SUBJECTS: The combined database used in this study comprised 3229 adults. RESULTS: Mean calcium, iron, folate and vitamin B6 intakes were very low particularly in women. Mean intakes of most micronutrients were lower in rural areas. Fortification of maize meal and wheat flour (bread) raised mean levels of thiamine, riboflavin, niacin, vitamin B6 and folate above the recommended nutrient intakes (RNIs). In women, despite fortification, mean iron intakes remained below the RNIs, as did calcium since it was not in the fortification mix. CONCLUSION: The average dietary intake of adults was of poor nutrient density, particularly in rural areas. Fortification of maize meal and wheat flour (bread) considerably improved mean vitamin B6, thiamine, riboflavin, niacin, folate and iron intakes as well as the overall mean adequacy ratio of the diet.  相似文献   
82.
Green labeled pectins were extracted by an environmentally friendly way using proteases and cellulases being able to act on proteins and cellulose present in cell walls. Pectins were isolated from different plant byproducts, i.e., chicory roots, citrus peel, cauliflower florets and leaves, endive, and sugar beet pulps. Enzymatic extraction was performed at 50 degrees C for 4 h, in order to fulfill the conditions required for microbiological safety of extracted products. High methoxy (HM) pectins of high molar mass were extracted with three different enzyme mixtures. These pectins were subsequently demethylated with two pectin methyl esterases (PMEs), either the fungal PME from Aspergillus aculeatus or the orange PME. It was further demonstrated that high molar mass low methoxy (LM) pectins could also be extracted directly from cell walls by adding the fungal PME to the mixture of protease and cellulase. Moreover, health benefit pectic oligosaccharides, the so-called modified hairy regions, were obtained after enzymatic treatment of the residue recovered after pectin extraction. The enzymatic method demonstrates that it is possible to convert vegetable byproducts into high-added value compounds, such as pectins and pectic oligosaccharides, and thus considerably reduce the amount of these residues generated by food industries.  相似文献   
83.
We investigated the influence of arbuscular mycorrhizae (AM) and dark septate fungi (DSF) colonisation on cadmium (Cd) accumulation in Arrhenatherum elatius from heavy metal-contaminated sites. AM colonisation disappeared when Cd concentrations in soil increased, while DSF infection was weak but constant throughout the experiment indicating that soil heavy metals are toxic to AM but not to DSF. AM colonisation was greatest when plant Cd concentrations were highest providing evidence that AM colonisation may influence Cd accumulation. In addition, the disappearance of AM and the concomitant reduction of Cd in shoots during seed maturation result in our suggestion that seasonal variation in AM may play a role in protecting developing seeds from soil pollution.  相似文献   
84.
Blastomyces dermatitidis is a common etiologic agent of fungal pneumonia in dogs. Definitive diagnosis is based on cytologic demonstration of the organism in affected tissues. Fluid obtained through transtracheal aspiration has previously been reported to have a low diagnostic yield for B. dermatitidis organisms. This retrospective study identified B. dermatitidis organisms in 76% of samples when transtracheal aspiration was performed in 17 nonsedated dogs with pulmonary blastomycosis. Transtracheal aspiration is a noninvasive and simple procedure that should be considered as an early diagnostic test whenever blastomycosis is a differential diagnosis in dogs with pulmonary disease.  相似文献   
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86.
Foliage of Afzelia africana, Pterocarpus erinaceus and Khaya senegalensis, from 10 trees per species, was collected every two weeks during the late dry, rainy and cool season to determine the seasonal effects on chemical composition. Fifteen rams of the Djallonké breed, weighing on average 20.0 kg, were used to evaluate the voluntary intake and digestibility of hay of A. gayanus, foliage of A. africana (as a sole feed), and A. africana, P. erinaceus and K. senegalensis offered with 30% of the diet as A. gayanus hay. The crude protein (CP) content of A. africana, and P. erinaceus decreased significantly from the late dry season to the cool season when that of K. senegalensis tended to increase. The mean CP of A. africana, P. erinaceus and K. senegalensis differed significantly (173 g, 139 g and 114 g/kg DM, respectively). The DM intake of A. africana offered with hay (571 g/d) or as a sole feed (598 g/d) were not significantly different, but was higher than that of P. erinaceus (428 g/d) and K. senegalensis (298 g/d). The digestibility calculated by difference of DM and CP of A. africana (582 g/kg DM and 795 g/kg CP, respectively) did not differ significantly from A. africana as a sole feed, but were higher than for the other species. The nutritive value of A. africana seems to justify the high preference of herders for this species.  相似文献   
87.
During the winter time in Finland, sunlight is inadequate for vitamin D synthesis. Many pet rabbits live as house rabbits with limited outdoor access even during summer and may therefore be dependent on dietary sources of vitamin D. The aims of this study were to report the serum 25‐hydroxyvitamin D concentrations in Finnish pet rabbits and to identify factors that influence vitamin D status. Serum 25‐hydroxyvitamin D concentrations from 140 pet rabbits were determined using a vitamin D enzyme immunoassay (EIA) kit. Eleven rabbits were excluded from the statistical analysis because of unclear dietary data. The remaining 129 rabbits were divided into groups depending on outdoor access during summer (no access n = 26, periodic n = 57, regular n = 46) as well as daily diet: little or no hay and commercial rabbit food ≤1/2 dl (n = 12); a lot of hay and no commercial food daily (n = 23); a lot of hay and commercial food <1 dl (n = 59); a lot of hay and commercial food ≥1 dl (n = 35). The range of serum 25‐hydroxyvitamin D concentration was from 4.5 to 67.5 ng/ml with a mean of 26.1 ng/ml. Statistical general linear model adjusted for weight, age and season indicated that diet was associated with vitamin D concentrations (p = 0.001), but outdoor access during summer was not (p = 0.41). Mean 25‐hydroxyvitamin D concentration was significantly higher in the rabbits receiving a lot of hay and commercial food ≥1 dl (33.9 ± 13.2 ng/ml) than in rabbits in other diet groups (24.0 ± 8.5 ng/ml, 21.7 ± 8.1 ng/ml, and 22.2 ± 18.0 ng/ml, respectively). This investigation showed wide variation in 25‐hydroxyvitamin D concentrations among Finnish pet rabbits. Diet remains a main source since outdoor access seems to be too limited to provide adequate vitamin D synthesis for most of them, and the use of vitamin D supplements is rare.  相似文献   
88.
89.

In the next two decades, the world population will increase significantly; the majority in the developing countries located in the tropics of Africa, Asia, Latin America, and the Caribbean. To feed such a population, it is necessary to increase the availability of food, particularly high-value animal protein foods produced locally, namely meat and dairy products. Dairy production in tropical regions has a lot of growth potential, but also poses a series of problems, particularly as dairy production systems were developed in temperate countries and in most cases are difficult to implement in the tropics. Drawbacks include hot weather and heat stress, the lack of availability of adequate feeds, poor infrastructure, and cold chain and the competition with cheap imports from temperate countries. This position paper reviews the major drawbacks in dairy production for the five major dairy species: cattle, water buffalo, sheep, goat, and camel, as well as the future trends in research and development. It also concerns the major trends in reproduction and production systems and health issues as well as environmental concerns, particularly those related to greenhouse gas emissions. Tropical Animal Health and Production now launches a topical collection on Tropical Dairy Science. We aim to publish interesting and significant papers in tropical dairy science. On behalf of the editorial board of the Tropical Animal Health and Production, we would like to invite all authors working in this field to submit their works on this topic to this topical collection in our journal.

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90.
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