Lead Toxicity Evaluation in Rams Grazing on Pasture during Autumn and Winter: A Case Study.

A study was conducted to appraise the levels of lead (Pb) in soils, pastures, and plasma of 20 rams raised in a farm alleged to have metal contamination. Samples of soil, pasture, and ram blood were taken four times with a one-month interval during autumn and winter, from October to January, and analyzed for Pb by atomic absorption spectroscopy. Considerable statistically significant differences were found in soil, pasture, and plasma Pb contents as a function of sampling time. The mean Pb values in soil ranged from 17.9 to 28.8 mg/kg, in forage from 9.92 to 16.4 mg/kg, and in plasma from 0.058 to 0.086 mg/l with a steady dwindle with sampling times. Forage Pb concentrations found in the present study were higher than the decisive Pb level for animals, but lower than the toxic limits for forage, signifying no anticipation of toxicity present in rams grazing therein. A significant positive correlation also was found between soil and forage and between forage and blood plasma Pb during this study. Overall, soil, forage, and rams contained tolerable amounts of Pb, so there is no risk of Pb toxicity presently to the rams being reared at the animal farm under study. [ABSTRACT FROM AUTHOR]