For an active dog that regularly visits ponds, rivers and stagnant puddles — particularly in the water disciplines covered in our articles on water rescue or dock diving — water is a source of enjoyment but also a vector for sometimes serious diseases.

Leptospirosis: a serious, transmissible disease

Leptospirosis is a bacterial disease transmitted mainly through rodent urine contaminating stagnant water. Dogs become infected by drinking or swimming in contaminated water, with the bacteria entering through mucous membranes or a skin wound.

Signs to watch for

Fever, listlessness, loss of appetite, vomiting, increased or decreased urination, jaundice in more advanced cases — symptoms that warrant a prompt veterinary visit, since the disease can seriously affect the kidneys and liver.

A public health issue

Leptospirosis is a zoonosis: it can be transmitted to humans, a factor that reinforces the importance of prevention for the whole household.

Vaccination

A vaccine exists and is part of recommended protocols, particularly for active dogs exposed to aquatic environments — a point worth discussing with your vet, in line with our article on vaccinating your dog.

Other water-related risks

Cyanobacteria (blue-green algae)

Certain algal blooms in stagnant water, particularly in summer, produce toxins that can be fatal if ingested. Water that looks unusually green or cloudy should be avoided absolutely.

Giardiasis

An intestinal parasite frequently transmitted through contaminated water, causing sometimes chronic diarrhea — a point that connects with the issues covered in our article on deworming.

Water intoxication (hyponatremia)

Rare but real, it occurs when a dog ingests an excessive amount of water while playing (retrieving objects in water, biting at a water jet) — a risk worth knowing about for dogs that intensively practice water disciplines.

Everyday prevention

  • Avoid suspect stagnant water, particularly during periods of intense summer heat
  • Bring plenty of clean water on outings, to reduce the temptation to drink from questionable sources, in line with our article on hydration accessories
  • Rinse the dog after swimming in natural water, drying the ears carefully to prevent the ear infections detailed in our dedicated article
  • Keep vaccinations up to date, according to the dog's actual lifestyle

A balance between enjoyment and vigilance

Water remains a valuable source of enrichment and exercise for many dogs. The goal is not to avoid it, but to choose healthy water sources and maintain suitable prevention — reasoned vigilance rather than excessive fear.

Also available in English: the ideal first aid kit for the active dog, the Bernedoodle: the crossbreed winning over families and the basics of dog training: recall and socialization. More translations are added over time.