Dog drinking from stream
Many dogs seem to love water the way I love a good peanut butter and jelly sandwich. During warmer months, I see them swimming in pools, splashing in lakes, hanging 20 on surfboards, and they always seem to be living it up.

There’s nothing wrong with that — in fact, water play is a wonderful way for dogs to stay cool in summer and wear themselves out at the same time — but bodies of water can hold hazards that might not be visible to the naked eye. Here’s what you should know about keeping your dog safe while he’s in the swim of things.

Microbial Soup

One water-borne risk is from Giardia, a microscopic protozoal parasite that infects the intestines when a dog ingests cysts (infectious offspring) shed in another animal’s feces. Often, dogs become infected through drinking contaminated water. Giardia is one of the most common intestinal infections we see in dogs (and cats).

Infected dogs may show no signs, but it’s not uncommon for dogs with Giardia — the condition is known as giardiasis — to get diarrhea, or “the squirts,” as it’s sometimes nicknamed. Other possible signs of giardiasis include vomiting, weight loss or lethargy (lack of energy).

Puppies are especially at risk, but older dogs can become infected as well. The best way to help prevent giardiasis is to ensure that your dog doesn’t drink potentially contaminated water, such as that from streams or other water sources where animals may have pooped. If you’re hiking or camping, carry fresh water for him, or filter or boil water before giving it to him. And just so you know, humans can also get Giardia, but they rarely get it from dogs.

Blue-green algae (cyanobacteria) is a toxic bacterial stew that can cause upper respiratory problems, affect the liver and neurological system, or even kill your dog if he drinks it. Found on lakes with poor water quality, the blue-green algal blooms can resemble green paint, pea soup, or thick blue or green foam. The water may stink or look scummy. Dogs can ingest the bacteria when they drink lake water or lick themselves after swimming in contaminated water. Keep your dog out of the water if you suspect a harmful algal bloom (HAB) and rinse him thoroughly with fresh water if he hops in before you realize there’s a problem.

Cyanobacteria are most common in mid to late summer, when water temperatures are likely to be high, but they can also occur in relatively cool water, too. Some cyanobacterial toxins can remain in water for days or weeks after the algal bloom disappears, so limit your dog’s lake outings for a while if you know a bloom has occurred.

Salty Dogs

Love tossing a bumper into the waves for your dog to retrieve? Just make sure he isn’t taking in a bumper full of salt water along with it. Drinking too much seawater can cause diarrhea, vomiting and the resulting dehydration. It’s not so good for his intestinal lining, either, which can become irritated by sand mixed in with the water. At the beach, be sure to offer your dog fresh water regularly, so he doesn’t try to quench his thirst from the ocean.

What about saltwater swimming pools at home? Their sodium content usually isn’t as high as that of ocean water. A dog who drinks a bit of this water isn’t likely to suffer salt poisoning, but you may notice that he drinks more and urinates more. It’s probably not harmful unless he has heart problems, in which case, it’s generally best to limit his exposure to salt.

Pool Pups

If you have a pool, your dog may spend more time in it than you do, especially if he’s a water-loving breed like a Labrador Retriever or Boykin Spaniel. The good news is that the occasional sip from a well-maintained pool is unlikely to cause your dog any stomach upset or other harm.

Of course, your pool shouldn’t be your pooch’s main source of water. Keep fresh water available indoors and out to help prevent him from taking in excess amounts of pool-cleaning chemicals or any bacteria or algae that may have taken up residence in the water.

Finally, to prevent skin and ear infections, rinse your dog with fresh water after a swim in any body of water. Treat the ears with a product recommended by your veterinarian, and make sure you dry the ears and skin thoroughly.

Splash away!

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