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Blue-Green Algae in Lakes Poses Threat to Dogs

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Most dogs love playing in the water. When you take your pooch for a walk by a lake then they will be itching to dive in but many lakes are harbouring a threat. Blue-green algae is a naturally occurring phenomenon which produces toxins that are potentially lethal for dogs.

If dogs are exposed to the algae, it can cause rashes when it contacts the skin and illnesses if swallowed. Dogs can ingest the toxins when they lick their fur after a swim. People can also be affected and should stay out of any affected water.

How Blue-Green Algae Forms

Blue-green algae forms when the weather has been unseasonably warm for an extended period of time and when there has been little wind or rain. There is no way to stop the algae forming but many bodies of water are monitored and warning signs are issued when the conditions are hazardous.

When water levels are normal the algae is evenly distributed, keeping the concentration at a safe level. But when water tables are low following a dry spell or hot weather, the concentration of algae increases and algae production grows. The algae eventually dies off and the gasses produced cause the algae to rise to the surface where it then finds its way towards the banks of the lake. This is when it poses a threat to swimming dogs and animals which have stopped to take a drink.

The symptoms of blue-green algae Poisoning in Dogs

The symptoms and their severity will depend on whether the toxin has affected the liver or has begun to impact the nervous system. Symptoms of liver poisoning include weakness, lethargy, diarrhoea, pale mucous membranes and changes in temperament.

Symptoms of nervous system toxicity include laboured breathing, Lethargy and difficulty moving, muscle tremors and fitting.

Blue-green algae poisoning can prove fatal. If you suspect that your dog may have come into contact with the algae you should take them to the vet immediately.

Treatment for Blue-Green Algae Poisoning

The quicker that you seek treatment, the better your dog’s outcome is likely to be. If your dog is seen shortly after they ingest the algae, then it might be possible to administer an emetic to induce them to vomit up the water. Activated charcoal can be used to absorb the stomach contents. If the toxin has reached the dog’s liver or nervous system, the vet will attempt to support their functions and to minimise the dog’s pain but they may not recover. Surviving dogs can have issues for the rest of their lives.

Keeping Your Dog Safe

You might be able to see the algae in the water but this is not always possible so you should never presume that any water is safe. You should be guarded after periods of hot weather, even with bodies of water which have proved safe before. Whenever your dog takes a swim, wash them off thoroughly as soon as you get home.


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