Resumen

DEPABLOS, Luis; GODOY, Susmira; CHICCO, Claudio F  y  ORDONEZ, Jorge. Mineral nutrition in cattle production systems in central savannas of Venezuela. Zootecnia Trop. [online]. 2009, vol.27, n.1, pp.027-038. ISSN 0798-7269.

To evaluate mineral nutrition in cattle production systems in the central plains of Venezuela, in well drained (WDS) and poorly drained (PDS) savannas as well as intermediate savannas (IS), nine cattle production units were selected in the municipal district of Pao de San Juan Bautista of Cojedes state, Venezuela, corresponding to a dry tropical forest. Soil, forage, animal blood serum, bone and liver samples were taken for chemical analysis. Ca, K, and Mg cations were higher than the critical levels required for forage production. Phosphorus content (ppm) was adequate in PDS (12.5), slightly lower in IS (9.0), and deficient in WDS (6.8). In forage, P was found to be adequate with values of 0.26 and 0.21% for PDS and IS, respectively, being deficient in WDS (0.12%). Calcium was higher in PDS (0.56%), followed by IS (0.39%) and PDS (0.26%) Magnesium, K, Na, and Cu content in forage was higher than the suggested critical levels for cattle, while Fe and Mn were very height. In blood serum, P was low with higher values in younger animals (4.16, 3.44, 3.34 mg/dL for calves, heifers, and cows, respectively). Hepatic Cu (98 ppm), Zn (129 ppm), and Mn (9.7 ppm) were adequate, while Fe (287 ppm) was high, in line with forage and blood concentrations. In bone tissue, Ca (21.7%, 243 mg/cm3) and P (9.9%, 106 mg/cm3) concentrations were deficient. It is concluded that P deficiency is present in the soil-plant-animal system, eventually Ca in some components of the system (blood serum, bone and forage) and high concentrations of Fe, Mn and Zn are present and may be involved in some antagonistic relationships.

Palabras clave : mineral nutrition; cattle; savannas.

        · resumen en Español     · texto en Español     · Español ( pdf )