An Episode of Zinc Toxicosis in Milk-Fed Holstein Bull Calves: Pathologic and Toxicologic Considerations
The potentially severe effects of Zn deficiency in mammals are documented; however, amounts of Zn required to induce toxicosis and signs of toxicosis are poorly understood.1–6 Though reports indicate that there may be a wide margin of safety in Zn supplementation of feeds for ruminants,5,6 other investigators have found that dietary Zn supplementation used to increase rates of gain and feed efficiency, to prevent footrot in sheep and infectious pododermatitis in cattle can result in death, fetal loss or reduced performance. The purposes of this investigation were to describe clinical signs associated with a natural outbreak of Zn toxicosis as well as tissue mineral concentrations, gross and histopathology.
KeywordsZinc Formalin Toxicity Manganese Paraffin
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