Sixteen Friesland heifer calves aged between 96 and 157 days were removed from a dairy farm that had been polluted with
vanadium and randomly allocated into two equal groups (n = 8). The objective of the trial was to determine whether
calcium disodium ethylenediaminetetraacetate (CaNa(2)
EDTA) could be used as a treatment for cattle running in environments high in background
vanadium. The treatment group received 80 mg CaNa(2)
EDTA per kg
body weight intraperitonealy (i.p.) twice a week over a 10-week period. The control group received
normal saline i.p. over the same period. During the trial calves were exposed to a daily intake of
vanadium in the form of contaminated tef hay derived from the farm of origin. In addition, the total mixed ration was spiked with a further 20 mg V(2)O(5)/kg feed to compensate for possible on-farm inhalation exposure. A stochastic model was used to estimate daily intake of
vanadium as a distribution function. The model estimated that the daily intake of
vanadium varied between an absolute minimum of 33 mg/day to an absolute maximum of 124 mg/day. The average intake of
vanadium was 71.8 mg per day per calf. Various chemical pathology parameters were measured throughout the trial as well as urine excretion rates of
vanadium and lymphocyte stimulation counts. All calves were slaughtered and necropsied in cohorts of 4-6 animals at monthly intervals after completion of the trial and withdrawal of
vanadium from the ration. Tissue concentrations of
vanadium were determined and necropsy findings were noted. The study found that CaNa(2)
EDTA appears to enhance the excretion of
vanadium in calves, but could not prove that the treatment had a protective effect against
vanadium exposure. Calves were able to tolerate the prolonged treatment with CaNa(2)
EDTA without side-effects.