Rodenticide toxic to pets

By Adelle Ellis, Times Reporter

Rodents can be extremely problematic to farmers, landowners and homeowners as mice seek refuge in outbuildings and homes, and gopher populations rise as new pups are born.
Local veterinarians are warning about the use of rodenticides and the effects they can have on pets.
“We understand that rodents can be problematic. Hiding rodenticides well and proper disposal of the rodenticides are extremely important (as) they retain their effectiveness for years,” said Dr. Jodi Viste, owner of Animal Care Centre of Strathmore.
Three common rodenticides that both users of the products and pet owners should be aware of include strychnine, anti-coagulant rodenticides and bromethalin rodenticides.
Strychnine induces potent convulsions that lead to the inability to breathe because of rigidity of the respiratory muscles. Although very effective at controlling rodents, very low doses of ingested strychnine are lethal to pets. Pets do not need to ingest strychnine directly, but can instead die due to strychnine poisoning by ingesting a gopher that has ingested strychnine. Within minutes of ingestion, the affected pet is likely to die due to the seizures, and since gophers do not restrict themselves to property lines, neighbouring pets of people who use strychnine are also at risk.
Anti-coagulant rodenticides such as Warfarin work through interfering with the clotting cascade, causing the affected rodent to die through bleeding out over the course of approximately one to four weeks. These rodenticides are very tasty for pets but are also lethal, although not immediately upon ingestion. Fatal amounts differ per animal size. The effects can be offset by giving your pet oral vitamin K1 and activated charcoal, and it is best to induce vomiting immediately after ingestion of a rodenticide to clear it out of the system before it reaches the small intestine.
One of the newest rodenticides on the market are bromethalin rodenticides. They are neurotoxic and very lethal in small doses. Signs of toxicity can be seen immediately with ingestion of a large amount of the rodenticide but can be delayed one to two weeks with ingestion of a small dose. Cats can ingest a lethal dose through eating an affected mouse. Symptoms can include excitation, muscle tremors and seizures, and when symptoms start to show, prognosis for recovery is very poor.
If you believe your pet has consumed a rodenticide, induce vomiting by giving the pet three tablespoons of hydrogen peroxide (which does not harm the animal except for causing vomiting) within a couple hours of rodenticide ingestion. From there a trip to their local veterinarian to administer activated charcoal and vitamin K1 ensures the best possible treatment.
“Pet owners need to contact a veterinarian immediately if they know of rodenticide ingestion. Induction of vomiting as soon as possible is usually in the pet’s best interest,” said Viste, who added poisoning can occur both through direct consumption of the rodenticide or through ingestion of the rodent that consumed the rodenticide.
Pet owners who are concerned their pets may have consumed rodenticide need to watch for signs, such as lethargy, weakness, pale mucus membranes, problems breathing, coughing up blood, bruising on the belly and bloody nose, and for tremors or seizures. It is not likely that poison can be transferred to another pet as they cannot receive poisoning through absorption.
If you purchase a property, inspect all outbuildings and sheds well for rodenticides before allowing pets to roam free, and dispose of them properly. Animals can be resourceful so it is warned that even poison placed out of reach can still be sought out by pets if they want to find it bad enough.
If you are concerned about the effects of rodenticides, seek alternative solutions to pest control such as having cats and dogs, setting rodent traps, hiring a professional exterminator, responsible gopher hunting, environmental controls such as keeping grass cut short and through smart storage of food and feed products to deter rodents.
“Before you purchase rodenticides make sure you know how it works, the risks involved and how it can potentially affect your pet,” said Viste.
Predatory birds and other wildlife are also susceptible to receiving poisoning through consumption of rodents who have ingested rodenticides.
Although rodenticides can be an effective measure of rodent control, local veterinarians warn to either use rodenticides with extreme caution or to seek out alternative pest control measures.
In Strathmore, Dr. Miguel Moncayo from the Strathmore Veterinary Clinic said it is not unusual for him to treat several pets a year that have ingested mouse poison, and that usually owners had the rodenticide hidden away and did not think it was accessible to their pets.
“If you don’t have to use mouse poison then just don’t have it on your premises; the best way to prevent it is just don’t have it. It’s not a reason to panic, it’s not an epidemic. But some people just need to be reminded once in a while,” said Moncayo. “Certainly, it’s much easier to prevent it than to treat it.”