Saturday, February 4, 2023



The good, the bad, and the algae

 Ask the RV Vet

With Dr. Deanna Tolliver, M.S., DVM

I’m currently at my favorite campground in Wisconsin. This morning I went to my (also) favorite coffee shop in Baraboo (Coffee Bean Connection – highly recommended) and I was curious as to why it was so crazy-busy. I asked the owner what was going on, and his response really surprised me. He said that most of the beaches on Wisconsin lakes in this area are closed because of blue-green algae. He surmised that the holiday crowds normally at the lakes were looking for other venues over the holiday.

Blue-green algae! That brought up some long-buried vet school lessons. Where I’ve practiced, it’s never been an issue. But it’s very dangerous for you and for your pets.

What it is
The technical name is cyanobacteria: They’re actually a bacteria rather than algae. They’ve been on this planet much, much longer than humans – like, around two billion years. For you botany fans, it’s thought that plant chloroplasts were originally cyanobacteria. They’re not all bad guys and are important parts of all aquatic ecosystems by providing nutrients to plants and releasing oxygen, to name a couple. If you’ve marveled at the colors of the hot springs in Yellowstone, you can thank cyanobacteria for that.

Even though they’re called blue-green, there can be many color variations of blue, green, brown or red. These microorganisms are always in the water. But when conditions are right – no wind (that would disperse them) and high temperatures (for growth) – there’s a population explosion. These “blooms” can look like large mats, scum or foam on the surface of the water.

Why it’s bad
It’s bad because it can produce two different toxins: microcystins and anatoxins. The first causes liver failure, and the second is a neurotoxin that can end in paralysis. 

Pets In The News–Famous dog in baked bean commercial dies; Huge cat found as a stray in Pasadena. And more! Click here to read.

The very ugly of the algae
Both of those toxins can cause death in as little as an hour in a dog that ingests the water containing them. If your dog has been in a lake or pond that may be contaminated, remove him from the water immediately and hose him off. It’s important that your dog does NOT ingest any of the pond water.

Because the symptoms can develop so quickly – literally within minutes – it might be prudent to head for a veterinary hospital right away. If you choose to wait, watch for these symptoms:

• diarrhea and vomiting
• blood in stool
• pale mucous membranes
• seizures, disorientation, coma 
• muscle tremors, rigidity, or paralysis
• difficulty breathing

Over 18 dogs have died in Minnesota from blue-green algae poisoning in the last ten years. One owner said, “We were playing fetch in the water when he went on shore, began vomiting and panting very hard, and just looked very sick.” They rushed their dog to a veterinarian, but once symptoms are present, the prognosis is very poor.

As long as conditions are right, the blue-green algae problem can exist no matter where you are. I’ve seen reports on dogs dying in Oregon, Minnesota, Wisconsin, Oklahoma, North Dakota, and Florida, among others.

If you take your dog with you to enjoy water sports – boating, swimming, fishing – don’t take any chances no matter how strong a swimmer she is. Put this life jacket on your pet. It’s available in several different sizes. The orange color helps you locate your pet faster if she’s in the water. Click here for more info.

There are also reports of dogs and cats dying from ingesting blue-green algae in water left in containers on decks and in yards! (ALWAYS have fresh water available outside for your pets.)

These toxins have no preference for species. There are many reported deaths in cattle, deer and other wildlife. Although there are no confirmed human deaths from cyanobacteria, people can become ill. For three days in 2014, Toledo, Ohio, residents were without municipal water: The system was shut down when microcystins from a huge algal bloom in Lake Erie were found in the water. Symptoms in people include abdominal pain, vomiting, diarrhea and skin rashes. Liver damage can occur with long-term exposure from drinking contaminated water.

The Centers for Disease Control recommend: “When in doubt, it’s best to keep out!” Don’t let your pets swim in, play in, or drink discolored or scummy water.

Now that you know, please share your knowledge with other pet owners who may not. Don’t let your dog drink or swim in any water containing algae!

Dr. Deanna Tolliver has been a full-time RVer for over 3 years, although she has been an RVer for several more. She travels with a fifth wheel and a 1-ton dually truck. Her travel companions include 4 small dogs and a 36-year-old Yellow-Naped Amazon Parrot. She has a BS and MS in biology and zoology, respectively, and a Doctorate of Veterinary Medicine from the University of Missouri, Columbia. She owned a veterinary hospital for many years and recently handed over the reins to a new owner. 


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