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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.
W pracy przedstawiono wyniki badań dotyczących zbilansowania energetyczne-białkowego dawek pokarmowych, stosowanych w żywieniu krów mlecznych rasy Brown Swiss oraz Holsztyńsko-Fryzyjskiej w certyfikowanym gospodarstwie ekologicznym. Oceny zbilansowania dawek dokonano, porównując zawartość energii oraz białka ogólnego we wszystkich paszach, wchodzących w skład dawki pokarmowej, ze składem dawki obliczonej na podstawie zapotrzebowania produkcyjnego krów. Badania wykazały wyraźną sezonowość zmian w ilości produkowanego mleka, zawartości tłuszczu i białka. Stwierdzono wyraźny wzrost wydajności mlecznej krów w okresie pastwiskowym. Podkreślono, że w warunkach gospodarowania ekologicznego prawidłowe ułożenie, szczególnie w okresie żywienia pastwiskowego, musi być regularnie kontrolowane, w zależności od fazy rozwojowej roślin.
Skład mleka zależy głównie od sposobu żywienia i utrzymania zwierząt, odmiennego w systemie ekologicznym i konwencjonalnym. Mleko ekologiczne zawiera więcej korzystnych białek niż mleko konwencjonalne, takich jak: α-laktoalbumina, β-laktoglobulina i laktoferyna. Mleko od krów wypasanych lub karmionych świeżą paszą, bogatą w różne gatunkowo rośliny, ma znacznie wyższy stosunek nienasyconych (PUFA) do nasyconych kwasów tłuszczowych (SFA) i korzystniejszy stosunek PUFA Ω-6 do Ω-3. Mleko ekologiczne ma większą zawartość PUFA, CLA cis-9, trans-11, kwasu t-wakcenowego (TVA) i kwasu α-linolenowego (LNA) w porównaniu z mlekiem konwencjonalnym. Profil kwasów tłuszczowych w mleku krów żywionych kiszonką z traw jest korzystniejszy w porównaniu z pozyskiwanym od zwierząt, którym podawano kiszonkę z kukurydzy. Czerwona koniczyna, siemię lniane, olej rzepakowy i rybny mają korzystny wpływ na skład kwasów tłuszczowych w mleku. Podczas okresu pastwiskowego mleko krów z gospodarstw ekologicznych miało większą zawartość witamin rozpuszczalnych w tłuszczach (A, D, E) od mleka zwierząt niekorzystających z pastwiska. Stężenie składników mineralnych w mleku krów z gospodarstw ekologicznych zależy od ich zawartości w glebie i w zielonce.
Influence of lactation stage on selected blood parameters and biological value of cow milk during pasture season in organic system of production. The disproportion between the cow's genetically determined ability to produce milk and the limits to improving the energy value of feed may be the cause of the metabolic stress of animals kept at organic farms. Negative energy balance has a major impact on the body's hormonal balance and the function of the organs; it also affects the content of basic components (protein, fat and lactose) in cows' milk. The aim of the study was to investigate changes in the biological value of organic milk obtained from high producing dairy cows at different stages of lactation during pasture season. The study was carried out on 68 Polish Holstein-Friesian primiparous. 272 milk samples were collected from cows which were in one of the following phases: the beginning of lactation (BL): 5-30 days postpartum); peak of lactation (PL): 60-90 days postpartum; full lactation (FL): 120-150 days postpartum); end/final phase of lactation (EL): 250 days postpartum. Stage of lactation had an overriding effect on the majority of analyzed milk constituents including: whey proteins, vitamins soluble in fat, phospholipids and fatty acids. The highest levels of lactoferin were found at the beginning of lactation (BL). At the same time, the β-hydroxybutyrate (BHBA) concentration increased, which confirmed that the fast growing milk yield at the peak of lactation is linked to an increase in energy demand. The lowest alanine aminotransferase and non esterified fatty acids activity was measured during BL. The study has shown a significant influence of lactation stage on the biological value of organic milk obtained from high producing dairy cows during pasture season. In addition, there is evidence that the organic production system has no influence on the metabolic profile of cows as the plasma parameters were within their standard norms. This might be the result of the positive effect of grass antioxidants.
The objective of the present study was to evaluate the fatty acid composition of cows milk, kept in a certified organic farm, independent of breed and season of nutrition. In the selected dairy farm, cows of two different breeds, i.e. Brown Swiss (BS) and Holstein-Friesian black and white (HF) between 45th–100th day of lactation, were managed under the same environment conditions. There were highly significant effects of the season on the SFA content in milk, where in SFA content were higher in the winter season compared with the summer season. The studies showed a significant influence of the season on the level of: BA, TVA, LA, CLA9, CLA10, EPA, DPA, DHA. Milk from BS cows was characterized by higher concentration of SFA, BA, AA, EPA and DPA during summer season of feeding. However, milk from HF cows was characterized higher concentration of MUFA, PUFA, OA, LA, TVA and CLA and lover of SFA. In the winter season milk from BS cows was characterized by a higher concentration of SFA, MUFA, BA, TVA and CLA compared with milk of HF breed. Finally, milk from HF breed in organic system during summer and winter season was characterized much higher nutritional value.
The aim of this study was to determine genetic effect of cow breed and feeding season on content of bioactive whey protein of cow's milk. In the selected biodynamic dairy farm, cows of two different breeds, i.e. Brown Swiss (BS) and Holstein-Friesian black and white (HF) were kept under the same environment conditions. The samples of milk were collected twice (in summer and winter) from 30 cows (in the same for number from BS and HF). Content of following whey protein: P-lactoglobuline (P-LG), a-lactoalbumine (a-LA), lactoferrin (Lf), lacto-peroxidase (Lp), lisozyme (Lz) and bovine serum albumine (BSA) were determined used RP-HPLC technique. The studies showed a significant effect of breed and feeding season on the content of whey proteins in milk. The average content of whey proteins in milk of cows ranged from 0.73% for the HF breed in winter to 0.84% for the BS breed in summer. Important differences weren't stated in the content of lactoferrin and lactopero-xidase in the milk, and for her the content fluctuated from 0.201 to 0.259 g/l and from 0.111 to 0.154 g/l appropriately at examined breeds. There were no statistically significant differences in the level of a-lactoalbumine in the milk of cows. Its content was ranged from 1.663 to 1.994 g/l. Statistically important differences were shown in conducted experience for the breeds and the feeding season (P < 0.01) for the content of P-lacto-globuline from BS cows in the period of summer feeding was 5.38 g/l, however reduced to the level herself by the winter 4.62 g/l. The similar trend was shown in the milk of HF cows in the summer season the concentration of this white was 4.60 g/l, and in the winter season underwent lowering up to 4.41 g/l. The experiment demonstrated statistically significant differences for the breed and feeding season for the content of P-lactoglobuline in cow's milk.
The objective of the present study was to evaluate the chemical composition and technological usefulness of cows milk kept in a certified organic farm. In the selected dairy farm, cows of two different breeds, i.e. (BS) and Holstein-Friesian (HF) between 45th–100th day of lactation, were managed under the same environment conditions. Results showed that in the summer and winter season milk yield, percentages of protein and fat, and also somatic cell score (SCC) were higher in milk of BS breed. However, protein to fat ratio, percentages of lactose and concentration of urea were higher in milk of HF breed. Only protein to fat ratio was higher in milk of BS breed during winter season. Milk from BS cows was characterized by a better usefulness of technological parameters, mainly lower coagulability time against the rennet and a higher of casein and beta-lactoglobulin content, which indicates that it is a better raw material for processors.
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