Metaldehyde Poisoning in Dogs

Slug bait is most commonly used in wet, coastal areas around the world. Toxicity manifestation to our canine friends usually occurs within a thirty minute to three hour time period. In most cases, poisoning results when a dog has access to stored slug bait, or when the application produces piles of bait over the garden or yard. The metaldehyde is available in liquid, dust, granular or pellet form, with the efficacy remaining for approximately ten days over the area where it was placed.

Slug bait poisoning is a very real threat to canines. The primary ingredient of the molluscicide, used to control slugs and snails, is metaldehyde. Because bran and molasses are often added to the bait in order to attract the garden inhabitants, the palatability is a danger to dogs and to other domesticated animals and wildlife. Ingestion of slug bait can be fatal.

The symptoms indicating that your dog may have ingested slug bait are listed below.

• Anxiety
• Asthma
• Drowsiness
• Cyanosis (bluish or purplish mucus membranes)
• Weakness of hind quarters
• Loss of body movement control (ataxia)
• Rapid heart rate (tachycardia)
• Excessive physical sensitivity (hyperaesthesia)
• Severe muscle tremor
• Body spasms and rigidity with arched back (opisthotonos)
• Excessive panting and drooling
• Vomiting
• Diarrhea
• Fever
• Loss of bowel and urinary control
• Seizure or convulsion
• Collapse and death

Types

Metaldehyde poisoning can occur through inhalation of the vapors (which causes serious injury to mucus membranes), ingestion (the most prevalent occurrence with dogs, which can lead to kidney and liver damage), and dermal absorption (can cause skin and eye irritation).

Poisoning by metaldehyde can result in eventual death if left untreated. Do not delay in taking your canine family member to the veterinarian if you suspect a case of ingestion. Irritation to mucus membranes and the lining of the gastric system can occur rapidly after exposure.

• Gastric acidity assists in the rapid chemical breakdown and subsequent production of acetaldehyde, both which are readily absorbed into the gastrointestinal tract
• The stomach contents that are present at time of ingestion, and the rate of gastric emptying will both have an effect on the toxicity of the slug bait
• The metaldehyde will be absorbed from the intestines, carried to the liver, and passed in the urine
• Slug bait alters enzyme activity
• Neuronal degeneration and swelling may be seen
• Also affected is the central nervous system, due to electrolyte disturbances
• The toxicity will decrease the threshold for convulsions
• The organ systems will experience necrosis (tissue death) when body temperatures rise dangerously high
• Liver, kidney and lung congestion can occur
• Profuse bleeding and hemorrhage is possible
• Summer months see more cases of slug bait poisoning because the use is more frequent than in other months

If you suspect that your furry family member may have eaten a portion of slug bait, it would be very helpful to the veterinary team to have the empty package or container of bait. Every bit of information available is a plus. If possible, as you make your way to the veterinary clinic, and you have not used snail bait yourself, have a member of your household call your neighbors to inquire if they have snail bait on their property.

Your dog may be vomiting; it could be likely that the stomach contents will have an odor similar to formaldehyde, or even an apple cider like smell. Blue pellets may be seen in the vomitus. It is possible that the stomach contents will be analysed for snail bait poisoning. This is the most accurate form of diagnostic confirmation.

Blood tests like biochemical profile and complete blood count, along with urinalysis could be done, but these tools do not always give your veterinarian a clear picture of the problem in this case.

Time is of the essence when treating slug poisoning in dogs. Because of this important factor for successful treatment, we must stress again the emphasis of bringing your dog to the clinic as soon as you become aware of the bait ingestion, or if unaware, as soon as symptoms appear.

Your pet will need to be hospitalised because rapid, aggressive treatment with careful monitoring will ensure the most positive outcome. Expeditious treatment, within 24 hours at the very most, can bring a full recovery within two to three days.

Your veterinarian will commence with a regimen including the following medical aids.

• If your pet is still in fairly good condition, vomiting may be induced
• If your dog is very ill, he will be given sedation and a gastric lavage will be done, once he is stabilised
• Careful monitoring will accompany intravenous therapy in order to correct electrolyte imbalances and metabolic acidosis (which is when the kidney produces too much acid that is not being removed from the body)
• Dehydration, if present, will be resolved
• Medication to reduce neurological implications, control seizures, aid in muscle relaxation, and to help tremor reduction will be given
• Nausea medication may be necessary
• Oxygen will be available if needed
• A warm water enema could be done to aid in the removal of metaldehyde from the gastrointestinal tract
• Active charcoal and cathartics (medication that increases the motility of the intestine and accelerates bowel movement) may be used

Though there is no antidote for slug bait poisoning, studies show that both metaldehyde and acetaldehyde are rapidly removed from the body.

When your much-loved pet returns home from the hospital, be sure to provide a quiet, serene resting area. Your veterinarian will have given you instructions on immediate home care and follow up. Caution must be used when storing snail bait in the future. Despite his ordeal, your pet may have developed a taste for the bait and ingest it again at the first opportunity.

You may decide to check with your local garden center for advice on natural deterrents for snails and slugs. There are alternatives like biological control, such as worms, or hand picking snails and slugs in the early morning, to remove them from your yard or garden.