The dog was being walked in Ecclesall Woods in Sheffield when the incident happened, and was left unable to walk following a bite from the UK's only venomous snake species.
The owners posted a sign on a tree trunk warning other dog walkers to be on their guard.
Adders, which are native to the UK, are common in woodland areas and open grassland, and can often be seen 'basking' in the sun during warm weather. Although they are not aggressive, they will bite if threatened or trodden on. Most bites occur between April and July, most commonly in the afternoon when the reptiles are active.
Their venom is not usually dangerous to humans, although there have been 14 deaths from bites since 1876, the most recent in 1975.
Dog owners are advised to keep their pets on leads in likely adder habitats such as sand dunes, rocky hillsides, moorland and woodland edges, and to prevent them from exploring undergrowth.
Vets4Pets advise that a dog which has been bitten should be kept still and taken straight to a vet. Common signs are pain and swelling, depression and lethargy. Over 96 per cent of dogs will make a full recovery after five days of treatment, although in a minority of cases complications can occur.