Page 460 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

Copper Chapter | 26 427

VetBooks.ir membranes. There may be hemoglobinuria, and death is to liver biopsy to assess liver copper concentrations. The
addition of elemental zinc to the diet (100 200 mg/day
common among severely affected animals. Postmortem
as the acetate) should be considered to reduce copper
findings include icterus, swollen liver, enlarged spleen,
and the kidneys appear dark, often referred to as gunmetal absorption.
blue or black kidneys. Antemortem testing of serum cop-
per often shows an elevation above normal, but this
CONCLUDING REMARKS AND FUTURE
decreases over time with a rapid decrease following fluid DIRECTIONS
therapy. Postmortem diagnostic testing for copper should
be performed on both liver and kidney. Mobilization of In trace amounts, copper is an essential element, but in
copper from the liver may reduce copper concentrations excess it is a toxicant. In general, sheep and certain breeds
to normal levels but the mobilized copper is then accumu- of dogs are more susceptible to copper poisoning. Copper
lated in the kidney. The ratio should be tested for both produces toxicity by multiple mechanisms. Poisoned ani-
copper and molybdenum. The close environment of the mals are usually treated with ammonium molybdate and
sheep should be inspected for extraneous sources of sodium thiosulfate. In addition, supportive care including
copper. fluid therapy and blood transfusion are beneficial.
Young dogs with genetic susceptibility to chronic cop-
per toxicosis may develop an acute syndrome of weak- REFERENCES
ness, vomiting, and anorexia. Older dogs may present
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