Effect of Pasture Trace Mineral Supplementation on Liver Mineral Levels and Feedlot Morbidity and Mortality

Abstract

Thirty-one Debouillet ewe lambs were exposed to elevated dietary copper (Cu) after being fed pelleted alfalfa from two separate feed mills which contained 33 and 45 ppm Cu. After consuming about 5.5 lb/day of this diet for approximately 50 days, signs of Cu poisoning became apparent (hemoglobinemia, hemoglobinuria). Cu toxicity was confirmed by a liver Cu concentration of 439 ± 36 (mean± SE) ppm in five dead animals. During the course of Cu exposure, eight of 31 ewe lambs died. Serum was collected from 10 ewe lambs showing extreme signs of Cu poisoning. Total, direct, and indirect bilirubin, and creatine kinase ( CK) were elevated in ewes consuming Cu. Ten extremely affected ewe lambs that had stopped consuming any feed received gelatin capsules (gavage) containing about 2 oz of a livestock salt/gypsum (76% calcium sulfate) mixture (2:1, weight basis) daily for 10 days. After 10 days of calcium sulfate treatment, serum bilirubin and CK were at or near normal concentrations and neither hemoglobinemia nor hemglobinuria were observed. Calcium sulfate administered in gelatin capsules appears to aid in the treatment of acute Cu toxicosis in sheep.