Unit 1 - Cu, Mo, Se Flashcards
What are the sources of copper for toxicity?
Feed/premixes, mineral blocks, injectable products, forage, water, and footbaths
In regards to dietary sources of copper for toxicosis, when do we typically get into problems?
Mis-mixes, off-label use, combination rations, and ration sharing
What species is extremely sensitive to elevated feed Cu levels?
Sheep
What elements are antagonists to Cu?
Mo, Fe, S, Zn, P, and Cd
What does thiomolybdate (Mo + S) do to copper? Where is it located?
It chelates it and decreases absorption
Located in the rumen
What are the different forms of copper?
Organic vs inorganic
Why is the absorption of Cu so low in rumininants and high in pre-ruminant individuals?
Ruminants have thiomolybdate in the rumen which ties up Cu and thus it is not absorbed. Non-ruminants do not have that
Where is copper excreted?
in the bile and feces
What is the MOA of copper?
There is Cu accumulation over time - when there is excess copper, the liver is completely saturated and there are high levels
Then there is a stress event and there is a massive release of that copper into the system
Initially the liver is able to compensate and store the Cu but then there is necrosis and Cu is no longer stored
Cu enters the blood stream and there is a hemolytic crisis and lysis of RBCs
What does Cu do once it hits the kidney? (this is a terrible question)
Changes its color - gun metal kidney
What stressful events can cause the massive release of copper from the liver?
Transport, handling, disease processes, extreme weather, attacked or chased, hepatotoxins, and consumption of garbage
What acute clinical signs are associated with copper toxicosis?
diarrhea, liver damage, and shock
Mimics As, Fe, and Se
When, during the copper toxicosis process, are there no clinical signs?
During the accumulation phase
What clinical signs are associated with post copper release?
Anorexia, weakness, depression, icterus, and hemoglobinuria (red wine urine)
What is the optimal sample for Cu status?
The liver
Why would we want the kidney if we have the liver in Cu toxicosis cases?
If there was a massive release of Cu then the liver concentration should be normal, however it will go to the kidneys once it leaves the liver so you may have high levels of Cu in the kidney
What samples are used for histopath exam in Cu toxicosis cases?
Fixed liver and kidney
Aside from liver and kidney, what samples are collected in Cu toxicosis cases?
Feed and feed labels
When will kidney values be elevated in cases of copper toxicosis?
Following a hemolytic crisis
Should you be concerned if there is a newborn ruminant with high liver Cu?
Do not be alarmed, during the last period of gestation, the mom is mobilizing her Cu to her calf
What will your clin path results be in a patient with copper toxicosis?
Elevated liver enzymes, red colored urine, and hemoglobin casts
What gross lesions do you see in a patient with copper toxicosis?
Icterus in the mucus membranes, visceral tissue, and fat Gun metal to black kidney Friable +/- yellow liver Hemolyzed serum (dark red to brown) Hemoglobinuria
What microscopic lesions do you see in a patient with copper toxicosis?
Necrosis, fibrosis, and infiltration of the liver
Renal tubular necrosis and hemoglobin casts
How is copper toxicosis treated on the herd level?
Decrease or eliminate Cu with Na molybdate (SLOWLY) and increase Zn to 100-200 ppm
