Rat bait: the background to this common poison for pets. Pete the Vet on Newstalk’s Pat Kenny Show

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Rodenticide – rat or mice poison – is a common cause of poisoning in dogs

This is because the poison agent is normally in a palatable, cereal-based formulation, so just as it is tasty to rodents, it’s also attractive to dogs
If the poison is not laid carefully so that it cannot be reached by dogs, there is a serious risk of dogs finding it, eating it, and being poisoned.
Cats do not find it palatable, so cats are only very rarely poisoned

Relay poisoning

There is a theoretical risk of cats being poisoned by eating rats or mice that have died of poisoning (this is known as “relay poisoning”)
In fact it is rare for this to happen – a cat would need to eat such a high number of poisoned rodents that it’s only seen in situations were rodents make up the majority of a cat’s diet (e.g. in a farm cat whose job it is to keep the rodent population down). If you think about it, only a small amount of poison is enough to kill a rodent, so to get a lethal dose, a cat would have to eat many small doses

Rat bait usually stops the blood from clotting

Most rodent bait works by stopping the blood from clotting, and that’s how it causes problems in dogs
High doses of Vitamin K are effective as an antidote to the poison, but this is not 100% effective, especially if dogs have consumed a large dose of rat poison

There are three situations where animals are presented to the vet with rat bait poisoning.

  1. When they have been seen to eat rat bait. In such cases, the vet will usually cause the animal to vomit (via an injection) and as long as this is done within an hour or so of the poison being eaten, it will successfully remove the rat bait from the stomach. The antidote – Vitamin K – will usually be given for a few weeks after in any case, to be double sure that there is not a problem.
  2. When the rat bait has been eaten more than an hour previously. The vet will then prescribe the antidote to the poison (which is Vitamin K) to prevent the onset of signs due to the blood not clotting. Other treatments – such as activated charcoal to limit absorption of the poison – may also be given.
  3. When it was not noticed that the poison had been eaten, and the dog is taken to the vet because of unexplained bleeding due to the blood not clotting.
    Sometimes this bleeding will be seen (e.g. from mouth, in vomit, in faeces or in urine) but sometimes it is internal (e.g. into thoracic cavity) and the animal just seems dull and unwell.
    In such cases, the vet will often find signs of internal bleeding (such as anaemia, with pale gums)

    This third group can be the most challenging to treat because all the vet knows is that the blood is not clotting properly and there are several possible causes of this:

  • Rat poison is the most likely cause
  • Lungworm is another possibility: dogs pick up this common parasite by eating slugs and snails (or just by eating grass). Lungworm causes coughing, but it also stops the blood from clotting, potentially causing crises like this.
  • The third possible cause is a type of haemophilia, an inherited or acquired deficiency of coagulation factors. These are rare, and are difficult to diagnose and treat.

Sometimes, with a bit of detective work, rat bait can be identified by the vet as the cause of the blood not clotting:
1) Detailed scrutiny of a patchwork of special blood tests such as Activated Clotting Time can strongly suggest rat bait poisoning
2) Sometimes blue granules or specks will be seen in the faeces: most rat bait is a bright blue colour and this is a clear sign that it has been eaten
3) Sometimes if people search around their neighbourhood, they will find a location where rat bait has been laid out

As well as Vitamin K dosing, many affected dogs need extra treatments, including a blood transfusion, a plasma infusion (blood with the cells spun down, but still containing clotting agents) and other intravenous fluids.
some dogs die despite all efforts to save their lives, especially if the poisoning is not noticed for a few days.
I recall cases where dogs have been seen to pass solid blue faeces because they have eaten so much rat bait: sadly, these cases have always died.

It is ALWAYS better to avoid rat bait poisoning of dogs by using such products carefully, well out of the reach of all pets.

Questions from listeners about pets

  • I took my Jack Russell to the vet over two weeks ago, he had a cyst that burst in his back. The Vet shaved the area and gave me Flamazine which I applied twice a day along with cleaning the area . I feel that he needs a powder of some sort to dry the area as it does not appear to be healing. What do you think we should do? Many Thanks Kate
  • I have a 4 month old Cocker Spaniel bitch (black). I have her since she was 8 weeks. She suffers from a ‘weak bladder’ i.e. when excited she urinates a little. So this means every time someone calls she drops a bit!!!! I have noticed she drinks a lot of water. I feed her dry nuts (Red Mill Puppy). I have had a number of cockers in the past and I have not come across this before. Regards Martin
  • Is there such a thing as training a kitten like you would a dog, I have a ten week old kitten and he just bites me all the time. Each morning as I am trying to get the kids ready for school he jumps up on the counter eats the kids toasts, bites the boys feet, constantly running around and hides in their school bags I know one day he will end up in the classroom with one of my boys. In other words is he just being a kitten and will he calm down. It’s like having a 3rd kid. Lucy
  • My dog Molly a 10 year old border terrier vomits bile like fluid. This happens at night time and is discovered in the morning. It happens about every three weeks. She is generally healthy. Fed twice daily on Royal Canin ( Skin care for small dogs) dose recommended for her size and Hypoallergenic feed for treats. She is 7.5 kgs in weight. Walked twice daily. Apart from this she is not very active. Any help appreciated.
  • My white westie has dry eye. It’s a common condition to them as far as I can ascertain. She’s 5 yrs old. I use cream which is 50 euro a tube…lasts about a month. Her eyes are always sticking shut. Any alternative treatment for her please!? Martin in Offaly
  • My collie has taken to her squeaky toy lately as if it’s a pup. She is 8. She sits on top of it and cleans ir and is mindful of it. She’s a bit quiet in herself since this started couple o weeks back? Normal or not? Ta. Colum Kildare
  • My dog likes bite at and catch flies as they pass her by, however sometimes I’m not sure there are any flies there and lately she has been snapping at the air for minutes at a time and quickly looking around her and staring at her paws. Any ideas? There are flies around but sometimes I honestly can’t see any. The other dog isn’t bothered at all!
  • One of my two dogs peed in the house yesterday for the first time. Weirdly they peed in the bathroom near the human toilet! They are indoors at night and indoors whenever we are home but if we are out they spend that time outside so they have lots of opportunity for toileting outside. I don’t know which dog peed indoors.. both are in great form and appear perfectly ‘normal’. Do I just ignore it…? Thanks Elaine

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