Molybdenum Toxicity

Molybdenum is an essential nutrient for all animals and is used in the synthesis of enzymes called molybdenoenzymes. Lack of proper nutrition can lead to molybdenum toxicity.

Deficiency

Molybdenum toxicity in livestock occurs when there isn't a proper intake ratio with copper. The normal copper-to-molybdenum intake ratio is 6 to 1. Toxic levels are reached when the ratio drops below 2 to 1.

Cause

Soil that is alkaline ( pH < 7) as a result of industrial contamination and subsequently treated with fertilizers containing molybdenum and lime produces plants that contain higher levels of molybdenum. Livestock consume these plants and develop molybdenum toxicity.

Symptoms

Depigmentation of the hair coat and skin around the eyes of cattle are signs of molybdenum toxicity. Decreased fertility, joint pain and anemia are also observed.

Diagnosis

To confirm molybdenum toxicity, blood or liver levels of molybdenum and copper must be determined as well as confirmation that the diet contains an unusually high amount of molybdenum relative to copper.

Treatment

Adding copper sulfate to the diet will reduce the effects of molybdenum toxicity. Copper glycinate injections are used as well.

References

• The Merck Veterinary Manual: Molybdenum Poisoning: Introduction