Weather Forecast


Ask the Vet: Algae can pose threat to pooch

Dr. Amanda Bruce


It’s finally getting hot out there.

Heading to the lake is part of the summer routine that many dog owners enjoy. Swimming can be excellent exercise for your pet, and a great way to cool off. But as you look to beat the heat with your dog, I want to offer a word of caution about warm, stagnant waters.

As summer progresses, we see nutrient content increase in bodies of warmer water. These conditions are ideal for the formation of something called blue-green algae. The scientific name for blue-green algae is cyanobacteria. Though referred to as algae, it actually is a photosynthetic bacteria.

As nutrient content increases in water, so can the concentration of blue green algae. Several toxins in the algae bloom can be life threatening to dogs can be found during a blue-green algae bloom.

The types of toxins found include hepatotoxins, which are poisonous to the liver, and neurotoxins, which can cause neurological problems. Both toxins can enter the dog either from drinking water containing blue-green algae or from licking their skin following a swim in contaminated water.

Blue-green algae is most likely to be found in pools of warm, stagnant water. It typically has an odor and looks like a slick of paint. It also can have a pea-soup appearance. Strong winds can blow blue-green algae along shorelines, making it easily accessible to dogs.

Keep your pet out of areas of water that look stagnant or discolored, and rinse your animal with clean water if you have any question about whether it has come in contact with contaminated water.

Not all areas of water that have a pea-soup appearance contain blue-green algae toxins. But because of the extreme consequences of animals ingesting small amounts of this dangerous substance, it is best to avoid any areas of stagnant water with your dog.

There is no specific antidote for blue-green alga poisoning. Some of the signs of neurological impairment include seizures, disorientation, extreme salivation and muscle tremors. Signs associated with liver toxicity include vomiting, diarrhea and yellow discoloration of skin. Early and aggressive treatment is essential to increase a poisoned pet’s chances of survival.

When planning to head out for a day on the water with your dog, think about heading to areas with a current or strong wave action to significantly decrease your risk of encountering a potential blue-green algae bloom. And keep your eyes open for this substance, which can make playing in the water with your pet extremely dangerous.

Dr. Amanda Bruce of Superior is owner of PetCare of Duluth, 2701 W. Superior St., Suite 102, Duluth. You can reach her or ask questions for future columns at or 218-461-4400. For more information about this subject go to