Violent spasms of pain, muscular contraction and twitching of the limbs, which become increasingly violent. The legs become rigid, the head thrown back, teeth clenched, and eyes staring, with great difficulty in breathing during the spasm.
Strychnine is the most usual poison as it is readily available. Dog owners should try to take precautions to lessen the risk to their pets.
The common vehicle for the poison is some form of meat, usually cooked and cut into small pieces. Sausages and chicken carcasses have been used also in the past.
Where possible the dog should be confined at night and before letting it out in the morning inspect the property for the presence of any unusual food substances or parcels which may contain meat. If any are found collect them and inform the police.
What symptoms does strychnine cause?
Symptoms of strychnine poisoning appear rapidly after the dog has eaten the poison. Depending upon the fullness of the stomach, the first signs can be detected from 30 minutes to one hour after swallowing it.
At first the dog appears restless, apprehensive and might walk stiffly. If handled, the muscles of its neck and abdomen are very tense. Soon violent muscular spasms occur, which causes the dog to extend its legs rigidly and arch its neck.
It tends to fall on its side during these episodes and while affected by violent contractions, it will stop breathing and its pupils will dilate. Loud noises, bright lights or handling of the dog stimulate further seizures.
The intervals between the episodes of muscular contractions become shorter and shorter. Eventually the heart and respiration are completely depressed and death follows while the animal is in a prolonged spasm.
How to treat strychnine poisoning in dogs
Treatment of strychnine poisoning is usually successful but is dependent on getting the dog to a veterinarian before the heart and respiration are irreversibly affected.
First-aid treatment should be aimed at keeping the dog as quiet as possible. Any attempt to make it vomit by forcing emetics into its mouth will only trigger more violent spasms.
The dog’s ability to swallow is impaired, so liquids are liable to find their way into the air passages. The dog should be handled very gently and be as quiet and calm as possible.
Ring your veterinarian to make sure he is able to see the dog, as rushing to the premises unannounced only to find he is away will only waste valuable time.
Veterinary treatment consists of giving an intravenous injection to counteract the muscle spasms. When these are under control, measures are taken to eliminate the poison from the stomach. The dog is then hospitalized so that more anti-convulsive drugs can be given should muscle spasms recur.
Snail bait poisoning in dogs
Each spring brings with it cases of snail bait poisoning in dogs. Puppies in particular find snail bait irresistible, but even old animals can become poisoned. Defender and Baysol are two popular types of snail bait.
Defender which contains metaldehyde, and Baysol which contains a poison upsetting the nervous control of the intestine. Both poisons can be fatal if a large amount is eaten, but of the two, Defender poisoning is the most difficult for the veterinarian to treat.
Metaldehyde (Defender) is a poison that causes no gastric irritation and therefore only when massive amounts have been eaten will the dog vomit. The first sign of poisoning is a lack of coordination in the dog’s movements. The dog will often be unable to climb stairs and will remain sitting.
On trying to get up tremors will be observed in the muscles of the legs. Depending on the amount of poison eaten these symptoms may take up to an hour to intensify. Eventually the muscle tremors become very marked and the dog will lie on its side with its muscles continually twitching.
These symptoms are similar to strychnine poisoning but with strychnine the muscle spasms are far more violent and tend to be intermittent, spasms often being induced by a loud noise or sudden movement.
Treatment of Metaldehyde poisoning
Treatment of Metaldehyde poisoning must be undertaken by a veterinary surgeon.
Attempts to make the dog vomit by giving emetics such as mustard and water are not successful. Where severe muscle spasms are present the dog may not be able to swallow and anything given by mouth can find its way into the dog’s lungs.
The veterinarian in these cases first anesthetizes the animal to counteract the nervous spasms. A stomach tube is passed and the stomach washed out to remove any free poison.
Of course by this time quite large quantities of the poison have been absorbed and it is necessary to maintain anesthesia until no further nervous spasms occur. This often is for a period of 36 to 48 hours.
Whilst the animal is unconscious for such a prolonged period its body temperature must be maintained. Fluids are given by transfusion and the animal’s position changed regularly.
The success rate of this treatment is high but is dependent on the amount of poison absorbed before treatment was begun. Large dogs have a greater chance of survival from massive poisoning than small dogs.
The margin of safety between the anesthetic dose and the lethal dose of the anesthetic used to counteract the effects of the poison is much greater in a large heavy dog than in a tiny dog weighing only a few kilos.
Poisoning with Baysol
Poisoning with Baysol pellets produces a completely different picture. Baysol causes violent gastroenteric symptoms.
In quite a short time the dog becomes very quiet, salivates profusely and soon starts to vomit. This is followed by severe purgation and straining, with the dog eventually passing only clear mucus.
If untreated the animal becomes very cold, depressed and weak and may die. Fortunately there is a specific antidote to the effects of this poison. Injections of Atropine sulfate quickly stop the violent muscular spasms of the intestinal tract and the animal rapidly recovers with apparently no lasting ill-effect.
How do I get rid of slugs and snails without harming my dog?
Snail baits can be used where there are pets quite safely if certain precautions are followed.
- First lock your pets up before spreading the snail killer. Puppies will be encouraged to investigate if they see their owner busily spreading something in the garden.
- Avoid leaving the preparation in piles and follow the manufacturer’s recommendation as to the rate of application. It is almost impossible for even the most addicted pet to pick up a dangerous amount if the pellets are spread evenly and thinly.
- Be careful to store the packet well out of reach of the pet. Many dogs are poisoned by eating massive amounts of pellets from a spilled package.
- Seek veterinary advice if you see your pet eating the pellets. The veterinarian can make the animal vomit quite easily before serious symptoms develop.