Poisoning of dogs and cats with Rodenticides

Rodenticides are most often from the group of haemorrhagic/anticoagulant poisons, which means that they are designed to kill rats, mice, and other rodents by internal bleeding. This is because they are Vitamin K antagonists and cause clotting disorders. Unfortunately, our pets are just as susceptible to these poisons as vermin, and seem to enjoy the taste!

Where do these toxins come from?

Easily accessible as it can be bought from any supermarket.

Poisoning usually occurs due to one of two reasons:

  • Animals get hold of poison that was not hidden correctly, or that has been carried around by rats.
  • Malicious poisoning.

Secondary (relay) toxicosis may occur in animals whose diets are composed mainly of poisoned rodents e.g. barn cats.

Examples of common products:

  • Efekto Supa-Kill  (Bromodiolone)
  • Rattex (Brodifacoum)
  • Finale (Difethialone)
  • Racumin (Coumatetralyl)
  • Mortein rat poison (Brodifacoum)
  • Muti-igundane Ratkiller (Coumatetralyl)

All of these products are so-called “superwarfarins”, compounds that were developed after rodents began to show signs of resistance to toxicity to first-generation compounds. What this means to pet owners, is that treatment with Vit K needs to be at much higher doses for a prolonged period of time to be effective, when compared to old poisons.

What are the signs of rodenticide poisoning? 

Depending on the dosage and the specific type of poison ingested, signs generally manifest 3-5 days after consuming the bait. Signs include:

  • Initial clinical signs are vague
    • Lethargy
    • Exercise intolerance
    • Decreased appetite
  • Sudden death is possible, without any clinical signs.
  • Generalised bleeding e.g. nosebleeds, blood in the urine, abnormal bleeding from any wounds (even minor ones) etc.
  • Pale mucous membranes such as the gums, which may contain blood spots.
  • Difficulty with breathing and/or coughing
  • Lameness and swollen joints

What should be done after an animal is poisoned?

An animal that is known to have ingested rat poison should immediately be taken to the veterinarian, as prompt treatment is necessary. The veterinarian will usually cause the animal to vomit – hopefully getting rid of most of the ingested toxin. Large doses activated charcoal will help prevent more poison being absorbed. And lastly Vit K1 treatment will be given depending on the type of rat poison that was ingested. Ideally the pet should be brought back to the vet practice after a period of time to check if its blood clots normally. This allows the veterinarian to see if the Vit K1 treatment should be prolonged or higher doses should be given.

Once clinical signs develop, treatment is extremely intensive and often animals need blood transfusions (to replace lost blood volume), plasma transfusions (for the clotting factors), oxygen supplementation and further supportive treatment.

Remember, a dog might seem perfectly fine for a few days after ingesting the poison, Therefore never wait to see if the dog gets ill before contacting your veterinarian!

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