Levels of Minerals in the Blood Plasma of Cows and Their Calves Fed from Buckets

Jagos P., V. Dvorak, J. Bouda: Levels of Minerals in the Blood Plasma of Cows and their Calves fed from Buckets. Acta vet. Brno, 50, 1981: 33-41. The concentration in plasma of calcium, magnesium, inorganic phosphorus, zinc, copper and iron in 40 cows and their calves up to the age of three months was followed in winter season under conditions of large-scale technology. The statistically significant decrease in Ca concentration and the increase in Mg, inorganic P and Fe in blood plasma was found in pre-partum cows as compared with post-partum ones. No significant variations were found in Zn and Cu plasma levels both in preand post-partum cows. The concentration in urine of calcium, magnesium and inorganic phosphorus in post-partum cows when compared with the pre-partum levels was found to be insignificantly higher. The plasma levels of calcium, inorganic phosphorus, zinc, copper and iron in calves prior to colostrum intake were higher than in their dams. The lowest plasma Ca, Mg, inorganic P and Zn contents were determined in calves from two to three weeks of age. The lowest Cu and Fe concentrations were found prior to colostrum intake and on the third day after birth, resp. The highest mean values in calves, as determined during the three 1\lonths' lasting experiment, were: plasma calcium 2.91 ± 0.27 mmol/l (two months old), magnesium 0.95 ± 0.10 mmol/l (age 1 day), inorganic phosphorus 3.52 ± 1.0 mmol/l (prior to colostrum intake), iron 48.84 ± 14.44,amol/l (prior to colostrum intake), zinc 42.25 ± 29.34,amol/l (age 3 days), and copper 16.39 ± 3.24,amol/l (age three weeks). Cow, calf, blood plasma, macroelements, trace elements, metabolism. Both veterinary diagnostics, therapy and prophylaxis and rational management of animal production, mostly in large-scale cattle production, necessarily require elucidation of the metabolic processes. E. g. Dobsinsky (1975) reports that metabolic disorders in calves in Czechoslovakia had been observed in 5.02 %, this percent being in fact higher owing to diagnostic difficulties. The study of macroelement metabolism has not only a scientific but also a practical significance in veterinary medicine. Many authors have investigated this problem in ruminants. The findings of Rowlands et al. (1974) suggest that even blood composition can usefully complement the selection of animals, possibly of breeds, in order to help to improve the growth potential. Little et al. (1977) have found a significant correlation between the weight gains, feed consumption and concentration of some blood metabolites. The increased weight of these followed calves correlated with serum concentration of iron as well. Payne et al. (1970) have reported on mineral metabolism in connection with performance of dairy cows. At our department we have examined the mineral levels not only in blood but also in urine, bone and other tissues and their relation to metabolic disorders (J agos et al. 1975a, b, c). The modification of low magnesium intake in 800 cows reduced the calf mortality from 8 -12 %