Assessment of Levels of V, Cr, Mn, Sr, Cd, Pb and U in Bovine Meat

Pollution of the environment with heavy metals can be a serious problem. In South Africa, particularly, there are many sources of heavy metals, often due to smelter and mining activities. This has led to toxic metals in the environment that directly affect air, water and food. The presence of heavy metal residues in foodstuffs is potentially hazardous to humans and animals. Heavy metals accumulate in certain organs, particularly in the liver and kidney. The objective of this study was to determine the levels of V, Cr, Mn,Sr, Cd, Pb andUin bovine organs and tissues obtained from polluted areas of North West Province, South Africa. Bovine liver, kidney, muscle, fat and bone samples were freeze-dried, homogenized and mineralized using a microwave-assisted digestion system. The levels were quantified using dynamic reaction cell inductively coupled plasma mass spectrometry(DRC-ICP-MS).A bovine muscle (NIST-RM8414) and bovine liver, reference material (NIST-RM1577b), were also analyzed and results agreed with certified values. The study revealed accumulation of Sr in bone, Cd, Pb and U in kidney and bone, Mn in liver and, V and Cr in kidney tissues of cattle.Keywords: Bovine meat, heavy metals, DRC-ICP-M

Standardization of cassava mahewu fermentation and assessment of the effects of iron sources used for fortification

Cassava root is the main staple for 70% of the population in Mozambique, particularly in inaccessible rural areas, but is known to be low in iron. Anaemia is a public health problem in mothers and preschool children in Mozambique and up to 40% of these cases are probably due to dietary iron deficiency. The World Health Organization (WHO) and Food and Agriculture Organization of the United Nations (FAO) recognize the fortification of foodstuff as an effective method to remedy dietary deficiencies of micronutrients, including iron. Cassava mahewu, a non-alcoholic fermented beverage is prepared at subsistence level from cassava roots using indigenous procedures. The aim of the study was to standardize mahewu fermentation and investigate if the type of cassava fermented, or the iron compound used for fortification affected the final product. Roots of sweet and bitter varieties of cassava from four districts (Rapale, Meconta, Alto Molocue and Zavala) in Mozambique, were peeled, dried and pounded to prepare flour. Cassava flour was cooked and fermented under controlled conditions (45°C for 24 h). The fermentation period and temperature were set, based on the findings of a pilot study which showed that an end-point pH of about 4.5 was regularly reached after 24 h at 45°C. Cassava mahewu was fortified with ferrous sulfate (FeSO4.7H2O) or ferrous fumarate (C4H2FeO4) at the beginning (time zero) and at the end of fermentation (24 h). The amount of iron added to the mahewu was based on the average of the approved range of iron used for the fortification of maize meal. The mean pH at the endpoint was 4.5, with 0.29% titratable acidity. The pH and acidity were different to those reported in previous studies on maize mahewu, whereas the solid extract of 9.65% was found to be similar. Lactic acid bacteria (LAB) and yeast growth were not significantly different in mahewu fortified with either of the iron compounds. There was no significant difference between cassava mahewu made from bitter or sweet varieties. A standard method for preparation and iron fortification of cassava mahewu was developed. It is recommended that fortification occurs at the end of fermentation when done at household level.Keywords: Cassava mahewu, fermentation, ferrous fumarate, ferrous sulfate, iron fortification, Mozambiqu

Prevalence of Brucella antibodies in sheep and springbok (Antidorcas marsupialis) reared together in the Karas region, Namibia

An outbreak of brucellosis in sheep in 2009 on a farm in the adjacent Hardap Region of Namibia and the lack of information on the brucellosis status of springbok prompted a serological investigation of brucellosis in sheep and springbok in the Karas Region, Namibia as these two species are utilized for meat. The main aim of the study was to find out if springbok reared with sheep are infected with brucellosis. Sera collected from sexually mature naïve sheep (n=332) and from springbok (n=345) on 11 randomly selected commercial farms and from adult sheep (n=472) and springbok (n=9) on eight commercial farms identified as positive for Brucella melitensis between 2008 and 2010 tested negative for Brucella antibodies. However, 10% (95% CI: 2.78-26.0) of the tested sheep on one farm tested positive for B. ovis antibodies confirming the presence of this agent in the region. On the eight exposed farms, both sheep and springbok tested negative for Brucella antibodies, providing evidence that control measures that were implemented following the detection of the disease had been effective. It was concluded that sheep and springbok on the eleven farms had not been exposed to Brucella melitensis and B. abortus infections and that on previously positive farms the infection had been eliminated in sheep and had not spread to springbok.Key words: springbok, sheep, Brucella melitensis, Brucella abortus, Brucella ovis, Namibi