Abstract
Five experiments were conducted to study the effect of molybdenum upon molybdenum and copper metabolism in the guinea pig. An excess of dietary molybdenum resulted in poor growth, excessive mortality and achromotrichia in colored animals. Copper was effective in alleviating the achromotrichia but only partially effective in overcoming growth depression. Molybdenum ingestion increased the molybdenum content of blood, liver, kidney and hair and decreased the copper content of hair. The addition of copper to molybdenum supplemented diets increased the copper content of kidney and hair. There are many similarities between the effects of molybdenum and the molybdenum copper interrelationships observed here for the guinea pig and those reported in the literature for ruminant animals. It is thus suggested that the guinea pig is a reasonably suitable experimental animal for basic work in this area which may have application to ruminants.