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The value of the routine analyses, applied until present, of whole blood, serum and urine for bioelements is limited. The blood mineral level does not often correspond to the content of minerals in the whole body because the composition of plasma results from supplementation of deficiencies by different homeostatic mechanisms. Moreover, the blood concentration of bioelements is relatively low and depends on a current diet, therefore the diagnostic value of such analytical results may be fairly small. Studies have shown that the analysis of hair and nails are an appropriate alternative for blood and urine tests or for biopsy. Chemical treatments in agriculture, animal production and food processing introduce many food contaminants into the food chain. Organic methods in agriculture are safer and therefore very important. Nutrition based on organically produced foods and anthroposophic lifestyle can play an important role in health prophylaxis The objective of this study was to determine correlations between concentrations of 29 major and trace elements in cow’s milk and hair. The experimental material consisted of 33 cows of Polish Holstein-Fresian (HF) breed from three dairy organic farms. All the farms were located in one climatic zone and under similar soil conditions. The cows were kept in traditional tiedup barns. The feeding was traditional, with ration components given separately. The cows were grazed from May to October. Depending on pasture yield and availability of other feeds, the feeding ration was supplemented with hay, straw, silage and cereals. Samples of milk and hair for analyses of minerals were collected in September, i.e. during the pasture feeding. The hair was taken from the poll. The concentration of Ca, K, Mg, Na, P, S, B, Ba, Co, Cr, Cu, Fe, Ge, I, Li, Mn, Mo, Ni, Se, Si, Sn, Sr, V, Zn, Al, As, Cd, Hg, Pb was determined. The content of toxic elements in milk was low and below the admissible level. The statistically significant positive correlations between concentration in milk and in hair were detected for such elements as Ba, Ge, Mo and Pb. In the case of major elements K and Mg and trace elements Al, As, Co, Fe, Hg, Se, Sr, positive correlations were observed but they were not statistically significant. Negative correlations occurred for such elements as Cr, Cu, I, Li, Ni, S, Si, Sn, V and Zn. It was only for V and Zn that they were statistically significant. Very low values (near zero) of coefficient r were observed for Ca, Cd, Li, Mn, Na, Ni, P, S and Sn. It seems that broader investigations of mineral composition of cow’s hair could be useful for establishing reference values for some elements and would make a contribution to better animals’ welfare.
Field experiments were conducted in two localities: Prusy (50°07’ N; 20°04’ E – one experiment) and Wierzbica (50°29’ N; 19°45’ E – two experiments) in 2003. The objective of this study was to analyse the influence of agronomic factors on the grain yield and on the content of macroelements in grain of different forms of naked oat. In Wierzbica the grain yield was determined statistically by the genotype, the phosphorus and potassium fertilization and the application of the plants growth regulator Moddus. In Prusy grain yield was determined only by the genotype (cultivars, strains). A concentration of macroelements in forms of oat was statistically different. In both localities the phosphorus and potassium fertilization and foliar application of urea, in general, had not the statistical influence on the content of the macroelements. An exception is the influence of the foliar application of urea on the content of potassium. Plant growth regulator Moddus caused changes in the content of macroelements. These changes were not always statistically significant, but always increased the concentration of macroelements. The second plant growth regulator Promalin did not cause changes in the concentration of macroelements.
In the first two years of study, method of cultivation did not affect the emergence of cucumber seedlings. In the third year, a drought occurring during the spring was the cause of poor seedling emergence on no-tilled plots. Six weeks after seed sowing, the shoots of cucumbers grown on the no-tilled plots were much shorter, especially in the last study year. At the time of cucumber seed sowing, no-tilled soil contained less phosphorus and potassium and in the middle of the fructification period the content of these elements in cucumber leaves was higher under no-tillage cultivation. Additional spring fertilization of rye with ammonium nitrate resulted in a higher N-NO3 content in soil and later in a higher nitrogen content of cucumber leaves. The content of calcium and magnesium in soil and than in cucumber leaves was independent of the cultivation method. In the first two years, method of cultivation did not affect the yield of cucumber fruits and in the third year the yield was much lower under no-tillage because of poor seedling emergence. Moreover, in the third year the fruits were smaller and dry matter content of the fruit was significantly higer under no-tillage cultivation.
The aim of this study was to determine the content of basic nutrients as well as selected macroand micro-elements in the albumen and yolk of eggs produced at large-scale, commercial poultry production farms (10) as well as in organic (8) and courtyard farms (12). Ten eggs were randomly collected 3 times on each farm. For chemical analyses, the eggs were hard-boiled for 15 min and then stored at a temp. of 4°C until analyzed. The albumen and yolk of hard-boiled eggs were assessed for the content of dry matter, total protein, crude fat and crude ash, and for their energy value (net Atwater equivalents) as well as the concentrations of K, Na, Ca, Mg, P, Fe, Zn, Cu, Se and Mn. No differences were observed in the content of dry matter, total protein and crude ash. However, differences were demonstrated for the crude fat content, the highest (P < 0.05) level of which was found in eggs from the organic system (higher by 60% in albumen and by 17% in yolk than in the other eggs), which was accompanied by an increased energy value of these eggs. In all the analyzed eggs, similar concentrations were noted for Mg (egg white) and P (egg albumen and yolk). The albumen of eggs from the organic system was characterized by the highest (P < 0.05) content of K, Na, Ca, Zn, Se and Mn. In turn, the albumen of eggs from large-scale commercial poultry production farms contained the highest (P < 0.05) levels of Fe, Cu and Se. Yolks of the eggs from the organic system accumulated the highest (P < 0.05) levels of K, Na, Ca, Mg and Fe. In turn, the highest (P < 0.05) concentrations of Zn, Se and Mn were determined in yolks of the eggs produced in the homestead system, and that of Cu – in yolks of the eggs from large-scale commercial production. A highly positive correlation between concentrations of minerals in the albumen and yolk of the analyzed eggs was reported for the following pairs: K-Na, Se (0.998, 0.93); Na-Na (0.949); Ca-Mg, Mn (0.994, 0.951); Mg-Ca, Mn (0.986, 0.982); P-Ca, Mn (0.997, 0.961); Fe-K, Mg, P, Zn (0.999, 0.937, 0.988, 0.999); Zn-Ca, Mn (0.999, 0.945); Se-Cu (0.971) and Mn-Ca (0.902), whereas a negative correlation for: Ca-Fe, Cu (-0.974, -0.994); Mg-Cu (-0.921); P-Fe (-0.933); Zn-Fe (-0.912); Cu-Na (-0.951); Se-K, P, Zn (-0.960, -0.910, -0.962) and Mn-Se (-0.979).
Field trials were conducted in 1999 and 2000 to investigate the effect of Striga gesnerioides and Alectra vogelii on the grain mineral elements' concentration of five cowpea varieties at harvest: IT82D-849, IT86D-534, IT89KD-245, KANO 1696 and SAMPEA7. The mineral elements analyzed were: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn) and zinc (Zn). Obtained data showed that the concentration of most elements was generally reduced in the grains of the cowpea varieties IT82D-849 and IT89KD-245 on both Alectra and Striga inoculated plots. On the other hand, cowpea varieties KANO1696 and SAMPEA7 showed a tendency towards having increased concentration of about 50% of the element analyzed in each year on both Alectra and Striga inoculated plots. In both KANO1696 and SAMPEA 7 there was a tendency towards the increase in the grain concentration of Mg and Zn and the decrease in K and Mn on Alectra inoculated plots and the increase in P and Mg but the decrease in Ca and Zn on Striga inoculated plots. The concentration of P in all the varieties in 1999 and 2000 (except IT89KD245 in 2000) was increased on Striga inoculated plots. Also, the concentration of Mg and N was increased in IT82D-849 on both Striga and Alectra inoculated plots in 2000. This study showed that, Striga and Alectra infestation generally reduced the mineral elements' concentration in the grains of cowpea varieties
Chromium accumulation and its effects on other mineral elements in Amaranthus viridis L. were investigated using inductively coupled plasma atomic emission spectrometry (ICP-AES) and resin adsorption. The aim was to understand why A. viridis can grow well in soils heavily contaminated by Cr, what the forms of Cr in soils and residues are, and what effects Cr has on the distribution of Mn. Fe, Cu and Zn in the plant. The results indicated that A. viridis is not a hyperaccumulator, although it can grow well in soil containing a high concentration of Cr. The Cr concentration in plant tissues from a contaminated site was about 11 times higher than in those from an uncontaminated site. At both the contaminated and uncontaminated sites, Cr was accumulated primarily in its shoots, and in roots in much lower concentrations. The levels of Cr in A. viridis tissues were as follows: leaf > root > stem. Cr occurred predominantly as Cr(III). There was very little Cr(VI) in the polluted soil where A. viridis grew close to a waste heap discarded by a chromium(VI) production factory. The possible mechanisms for Cr accumulation of A. viridis and the effects of Cr on uptake and accumulation of the other mineral elements in A. viridis are briefly discussed.
Six types of rootstocks were planted at Warsaw-Wilanow, Central Poland in spring 2002: three originated from Pyrus communis – Caucasian pear seedlings, OHxF 333 and 'Pyrodwarf' and three from Cydonia oblonga – quinces S₁, MA and MC. In August they were budded with Conference and Erika pear cultivars. Mid-shoot leaves, taken at the end of August from rootstocks (in 2002) and from maidens budded on them (in 2003) were analysed for Ca, Mg, P and K content. Rootstocks differed significantly in the content of all mineral elements studied. They also affected the leaf mineral composition of maiden trees budded on them. The leaf Ca, P and K content depended on cultivar as well. A significant interaction of rootstock × cultivar on the leaf P and K content in maiden tree leaves was also noted. It has been suggested that the information about a specific abilities of rootstocks to absorb particular nutrients may serve as an additional indicator in selection of optimal rootstock for certain soil conditions.
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