TOADS

Certain species of toads can be very poisonous to pets, including the Sonoran Desert or Colorado River toad (Incilius alvarius; formerly known as Bufo alvarius) and the Marine or Cane toad (Rhinella marinus; formerly known as Bufo marinus). These toads are very large in size, often reaching 8 or 9 inches when mature and are typically only found in certain parts of North America, including the region between Arizona and California and in Florida, Texas, Hawaii, and other tropical areas (respectively). The Marine toad is considered to be more poisonous, and most dogs poisoned by these toads will die if untreated. Just holding the toad in the mouth can result in poisoning and death. Dogs can even be poisoned by drinking the water out of the container that a toad sat in.

Poisoning is due to toxins called bufotoxins and bufodienolides and biogenic amines found in the toad’s parotid glands and skin. Mouthing, chewing or otherwise playing with the toad causes compression of the glands and secretion of the poison. Contact with the mucous membranes or ingestion can result in severe, immediate drooling, followed by an elevated temperature, brick red mucous membranes, abnormal heart rhythms, difficulty breathing, seizures, and even death.

NEWTS

These slimy creatures can cause serious health risks if consumed or chewed on by your pet. Not all newts are harmful to household pets and farm animals, but there are two newt species that can be particularly dangerous upon ingestion. The Red-Spotted Newt located in eastern USA and the Rough-Skinned Newt located north of Francisco Bay, California can both secrete tetrodotoxin. Tetrodotoxin is an extremely potent poison found in the white fluid-like secretions that these newts exude. Consumption of either of these newt species can lead to progressive muscle paralysis, respiratory distress, and seizures. Treatment typically involves rinsing the mouth, supportive measures provided by a veterinarian, and possible surgical removal of the newt if completely consumed.

SPIDERS

Spiders can create a serious health risk for your pet if they are bitten by a venomous species. Luckily, most spider species are minimally or non-venomous! However, species to be aware of are the female Black Widow located throughout North America, the female Brown Widow located in southern and western USA, and the Brown Recluse spider located in southern USA.

Female Black and Brown Widows can be very dangerous, because they have prominent venom glands and can deliver a large venom dose with their bite. The male spiders of this species rarely inflict significant venom with their bites due to their smaller fang size and the inability to effectively penetrate the skin barrier of humans and animals. If bitten by a female Widow spider, common clinical signs include muscle pain and redness at the site of the bite, weakness, tremors, seizures, and respiratory distress. Treatment for Widow spider bites includes anti-venom and supportive care provided by a veterinarian.

There is a large range of variability when it comes to envenomation from the Brown Recluse spider, also known as the violin spider. The majority of bites from this species are insignificant, however the presence of clinical signs indicates significant envenomation. If significant envenomation has occurred, common clinical signs include skin necrosis at the site of the bite, fever, vomiting, and weakness. There is no antidote for Brown Recluse spider bites, but treatment includes fluid therapy and supportive care provided by a veterinarian.