Cane toads (Rhinella marina) are large, heavy-bodied frogs that are native to Central and South America. They were introduced to many places around the world, including Australia, in misguided attempts to control agricultural pests. Cane toads secrete a potent toxin from glands on their back and shoulders that is very dangerous and sometimes fatal if ingested by dogs and other animals.
What is cane toad poisoning?
Cane toad poisoning occurs when a dog ingests or comes in contact with the toxins secreted by a cane toad. The poison is called bufotoxin and contains chemicals such as bufotenin and bufagins that are severely toxic to dogs. It is present in high concentrations in the toad’s skin secretions, egg yolks, ovaries, liver, and other organs.
The toxins affect a dog’s nervous system, heart rate, and blood pressure. Even small amounts can cause drooling, head shaking, vomiting, weakness, loss of coordination, paralysis, convulsions, coma, and sometimes death in worst case scenarios. The poison can be absorbed through the mouth, nose or eyes after coming in contact with the toad or its toxins.
What are the symptoms of cane toad poisoning in dogs?
The symptoms of cane toad poisoning in dogs can develop extremely rapidly, usually within 15-30 minutes after contact with the toad or its secretions. However, the onset of symptoms ranges anywhere from 5 minutes to a few hours depending on the dose of toxin absorbed.
Common signs and symptoms include:
- Excessive drooling and mouth irritation
- Repeated swallowing motions and excessive pawing at the mouth
- Head shaking
- Crying or whimpering in pain
- Vomiting and retching
- Loss of coordination and balance
- Wobbly gait or falling over
- Weakness, collapse or paralysis
- Dilated pupils
- Panting
- Rapid heart rate
- Bloody urine or stool
- Seizures or muscle tremors
- Coma
How long does it take for cane toad poisoning symptoms to appear?
In most cases, the first symptoms of cane toad poisoning begin within 15-30 minutes after a dog ingests or comes in contact with the toxins. However, the timing can range considerably depending on these factors:
- The amount of poison absorbed – larger doses cause faster onset of symptoms
- The specific toxins involved – bufotenin acts quickest
- The size and breed of the dog – smaller dogs tend to be affected sooner
- Method of contact – ingestion leads to faster absorption than skin contact
- Location of contact – mouth and nasal mucosa absorb faster than skin
While 15-30 minutes is average, symptoms can appear in some cases:
- Within 5-10 minutes if a large amount was ingested or made contact with the mouth/nose
- After 1-3 hours if only a small amount briefly touched the dog’s skin
- 12-18 hours later as a late-onset reaction in rare cases
Stages of cane toad poisoning symptoms
The symptoms of cane toad poisoning progress through several stages as the toxins take effect:
Stage 1 (5-30 minutes)
- Excessive drooling, repeated swallowing
- Pawing at the mouth
- Head shaking
Stage 2 (10 minutes – 2 hours)
- Vomiting, crying, whimpering
- Wobbly gait, incoordination, falling over
- Weakness, paralysis in the hind legs
Stage 3 (30 minutes – several hours)
- Tachycardia (elevated heart rate)
- Bloody urine or stool
- Dilated pupils
- Panting
- Muscle tremors, seizures
- Coma, death
Progression depends on the severity of poisoning. Mild cases may only show early signs like drooling and recover quickly. Severe cases rapidly advance through all three stages.
How long do cane toad poisoning symptoms last in dogs?
The duration of cane toad poisoning symptoms depends on factors like the toxin amount and how quickly treatment was received. With prompt veterinary treatment, symptoms may resolve within:
- 2-3 hours in mild cases
- 12-24 hours in moderate cases
- A few days in severe cases
In treated dogs, early symptoms like drooling and vomiting typically resolve first. More severe effects like bloody urine, seizures and coma can persist for longer. Dogs who survive the most critical 24-48 hour period often make a full recovery over a few days with supportive care.
Without treatment, symptoms will progressively get worse and can lead to death in as little as 6-12 hours. Dogs who survive may have lasting effects like impaired coordination or seizures.
What factors influence the onset and duration of cane toad poisoning?
The speed of onset and overall duration of cane toad poisoning depends on several key factors:
- Amount of toxin exposure – larger doses act faster and cause more severe, longer-lasting symptoms
- Route of toxin exposure – ingested toxin is absorbed more quickly than skin contact
- Dog’s size and breed – smaller dogs tend to be more rapidly affected
- Health status – dogs with underlying issues may experience more severe, persistent symptoms
- Speed of treatment – fast veterinary treatment limits absorption and duration of toxicity
How is cane toad poisoning treated in dogs?
There is no antidote for cane toad poisoning. Treatment focuses on supporting the dog through the effects while limiting toxin absorption and excretion. Key elements may include:
- Inducing vomiting if ingestion just occurred
- Gastric lavage under anesthesia to flush toxins from the stomach
- Activated charcoal to bind toxins in the GI tract
- IV fluids to maintain blood pressure and kidney function
- Medications to control heart rhythm disturbances
- Seizure control medications if needed
- Respiratory support such as oxygen therapy
- Monitoring of kidney function, electrolytes, blood cell counts
With aggressive veterinary treatment and supportive care, most dogs recover fully within 2-3 days, though severe cases may take longer. Dogs who develop kidney damage or other secondary issues may need extended care.
How can I prevent cane toad poisoning in dogs?
Prevention is the best way to avoid this life-threatening toxicity. Steps to help safeguard dogs include:
- Being aware of areas populated with cane toads
- Keeping dogs indoors or leashed in high-risk zones
- Avoiding walking near creeks or wetlands after dark when toads are most active
- Teaching dogs to avoid toads and their secretions
- Blocking off garden ponds or water features where toads may gather
- Checking your yard carefully and removing or humanely relocating any invading toads
- Using fencing around your property to prevent toad access
Prompt action is also key if poisoning does occur – seek veterinary treatment immediately at the first signs of drooling or distress after any suspected contact.
What is the prognosis for dogs with cane toad poisoning?
With appropriately timed veterinary treatment, dogs have an excellent prognosis after cane toad poisoning. The vast majority (over 90%) will make a full recovery within 2-3 days. However, the outlook depends on these key factors:
- How rapidly treatment was started – delay worsens absorption of toxins
- The severity of clinical signs – more advanced symptoms indicate higher toxin levels
- How the dog responds to initial therapy – lack of improvement is a concern
- Whether kidney damage or other secondary complications develop
- The dog’s overall health status prior to poisoning
Even with treatment, mortality rates from cane toad poisoning range from 10-25%. Death usually occurs within 6-12 hours due to cardiovascular collapse or respiratory paralysis. Dogs who survive the initial critical period generally recover well and leave the hospital within 2-3 days.
Key points about cane toad poisoning in dogs
- Cane toad toxins can cause life-threatening poisoning in dogs with drooling, vomiting, weakness, collapse, seizures, coma, and sometimes death
- Onset of symptoms typically occurs within 15-30 minutes but can range from 5 minutes to a few hours based on toxin dose and route of exposure
- Prompt veterinary treatment is vital – supportive care limits toxin absorption and allows most dogs to recover fully in 2-3 days
- Prevention through awareness and blocking toad access is key to avoid this serious toxicity
Conclusion
Cane toad poisoning is a rapidly progressive and potentially fatal toxicity that dogs are extremely sensitive to. Timely veterinary care is absolutely crucial for survival and recovery. While most dogs exhibit symptoms within 15-30 minutes after contact, onset can vary from just minutes to a few hours based on toxin dose and absorption factors. With appropriate treatment, symptoms usually resolve after 12-24 hours but may persist for 2-3 days in severe cases. Public education on prevention is vital, as these introduced toads pose an ongoing threat to the lives and health of our canine companions.
