• 2014-wvma-conv-logo

  • projectbreathe
  • wvma continuing ed
  • Find-a-Vet
  • animal-owners

Donation Banner

August 2010

Stay Healthy, Swim (and Drink) Clear of Algae

The Wisconsin Veterinary Medical Association reminds pet and livestock owners to steer clear of algal blooms when allowing animal access to water sources during the summer.

Blue-green algae, also known as Cyanobacteria, are a group of photosynthetic bacteria that many people refer to as "pond scum." These microorganism blooms occur any time from late spring to early fall, but are most prevalent in July and August and can be found in both large and small water bodies, fresh and brackish.

Blooms occur in warm, sunny weather with temperatures ranging from 50 to 86 degrees Fahrenheit and where higher levels of phosphorus and water nitrogen are found.

“We don’t know why, but sometimes (fortunately rarely) the blue-green algae bacteria produce toxins that can affect the skin, the gastrointestinal tract, the liver, the central nervous system and other organs, says Dr. Linda Sullivan, a clinical instructor in the UW School of Veterinary Medicine Pathobiological Sciences Department.  “These toxins can be deadly when ingested by people or pets.”

Animals most commonly affected include dogs and cows since they are most likely to come in contact with blue-green algae.  And they usually don’t care as much about that yucky slime layer on the water as people do! 

What can you do to keep your animals safe? 

Don’t let animals drink or submerse themselves in water that has blue-green algal blooms. For livestock, clean water collection vessels regularly and restrict access to water sources containing algal blooms.   

“Be sure to rinse off or bathe dogs that have been swimming in algae-infested water before they groom themselves,” adds Dr. Sullivan. Individuals washing or handling the dog should wear protective gloves and avoid direct contact with algae.

Clinical signs of poisoning in dogs can vary from anorexia, lethargy, vomiting, diarrhea, and even seizures and death. 

In cattle, toxins can affect the liver and the nervous system. Similar to dogs, clinical signs include salvation, excess tear production, urination, diarrhea, tremors, convulsions and death.

See your local WVMA member veterinarian right away if your animal displays any of these signs after coming in contact with an algal bloom.

Additional information on blue-green algae and its implications on human and pet health can be found on the Wisconsin Deptartment of Natural Resources website,

For more information contact your local WVMA member veterinarian or visit

2014 Convention

Find a Vet

Site Login

NOTE: The login required here is the GENERAL WEBSITE login that will allow you access to the PROFILE LOGIN section. We have set up dual login pages for your security. DO NOT try and use your PROFILE login here. After three failed login attempts, your IP address may be blocked, preventing you from accing the website. If this happens, please visit and email WVMA your IP so that we may verify you and unblock it. The security of your information is of the utmost concern for us. We apologize for any inconvenience that our security measures may have caused you.