Anticoagulant Rodenticides Flashcards
What are the 1st generation Anticoagulant Rodenticides?
Warfarin
Pindone
Chlorphacinone
What are the 2nd generation Anticoagulant Rodenticides?
Brodifacoum
Diphacinone
Bromodialone
How are animals exposed to Anticoagulant Rodenticides?
Ingestion
Relay (Secondary) toxicosis
Malicious poisoning
Secondary Toxicosis
eating poisoned rodents
What is special about the toxicity of 1st generation Anticoagulant Rodenticides?
most toxic when ingested daily for about a week
What is special about the toxicity of 2nd generation Anticoagulant Rodenticides?
effective after one dose
Anticoagulant Rodenticide Properties
Odorless
Colorless
Resistant to the environment for weeks to months
What are the factors enhancing toxicity of Anticoagulant Rodenticides?
Vitamin K deficiency
Liver disease
enzyme inhibitors
concurrent use of drugs that may displace the anticoagulant from protein binding sites
Concurrent factors that cause hemorrhage, anemia, hemolysis, trauma, surgery
Administration of steroids or thyroxine may increase receptor site affinity
Anticoagulant Rodenticides toxicokinetics
largely bound to plasma proteins Higher concentrations in the liver Metabolized in the liver by hydroxylation Crosses the placenta excreted in milk
When do Anticoagulant Rodenticides reach peak blood levels?
6-12 hours
What is the half life of the 1st generation Anticoagulant Rodenticides?
19 hours
What is the half life of the 2nd generation Anticoagulant Rodenticides?
108-144hours
What is the mechanism of action of Anticoagulant Rodenticides?
Inhibit vitamin K epoxide reductase
Reduced carboxylation and activation of precursors of clotting factors II,IV, IX, X (1972)
What factors are affected by Anticoagulant Rodenticides?
Factors X,IX,VII, II
“1972”
When do you see clinical signs of Anticoagulant Rodenticides?
1-5 days
What are the clinical signs of Anticoagulant Rodenticide toxicosis?
Signs of hemorrhage: Epistaxis, bloody discharge from orifices, hematuria, bleeding from venipuncture, hematomas, weakness, shock, tachypnea, anorexia, lethargy
What does Anticoagulant Rodenticide toxicosis cause in cattle?
Abortion (placental hemorrhage)
What are the lesions seen in Anticoagulant Rodenticide toxicosis?
Intrapulmonary, intrathoracic/abdominal hemorrhage, petechiation, ecchymosis
Where do you detect Anticoagulant Rodenticide toxicosis in live animals?
blood
plasma
serum
Where do you detect Anticoagulant Rodenticide toxicosis in a dead animal?
Liver
GI contents
vomitus
sample of bait
What are the clinical pathology signs seen in Anticoagulant Rodenticide toxicosis?
Prolongation of: ACT PTT PT PIVKA
ACT
Activated Clotting time
PT
One stage prothrombin time
APTT
Activated partial thromboplastin time
PIVKA
Proteins induced by vitamin K antagonists
What are other laboratory signs seen with Anticoagulant Rodenticides?
Anemia
Thrombocytopenia
Hypoproteinemia
Radiographic changes from hemorrhage
How do you treat Anticoagulant Rodenticide toxicosis?
Oral Vitamin K 1 therapy
Decontamination: Emesis if recently ingested
Administering clotting factors (Fresh Frozen Plasma)
How do you treat a patient with bleeding and a PCV greater than 15-20% and stable from Anticoagulant Rodenticide toxicosis?
Vitamin K therapy
Clotting factors
Fresh Whole Blood
How do you treat a patient with bleeding and a PCV less than 15% and unstable from Anticoagulant Rodenticide toxicosis?
Give clotting factors
Fresh Whole Blood or Fresh Frozen Plasma
Vitamin K
Supportive Care
How long should the treatment continue for?
Warfarin = 1 week
2nd generation = 4 weeks
What is the prognosis for Anticoagulant Rodenticide toxicosis?
Generally treatable depending on where the hemorrhage is
