Insurance companies say the trend, which they expect to continue, is a result of the increasingly litigious nature of society, and not of sloppiness among vets.
But they say the rise could pose problems for the profession, particularly if people succeed in claims for nervous shock and distress caused by the loss of a pet.
At present, many claims are settled before they reach court with vets offering a few hundred pounds to replace a dog or cat. But in California, lawyers have managed to win thousands of dollars for their clients after arguing that their lives have been ruined by vets' negligence.
'What happens in the US tends to come over here sooner or later,' a barrister said last week.
In 1991, the last year for which figures are available, the Veterinary Defence Society, which insures vets against claims of negligence, dealt with 727 cases, just under half of them from dog and cat owners. Most were settled out of court. Sources close to the society say the number of claims has risen steadily and will continue to do so.
In one case, the owner of a labrador was paid about pounds 200 after it died during an operation. She said it was given an overdose of anaesthetic. But although she said she was 'devastated' by the labrador's death, she was only compensated for her 'economic loss' and not her mental anguish.
Charles Foster, a qualified vet and practising barrister, said the British courts have yet to rule on a case where someone is demanding compensation for the 'sentimental value' of their animal. 'But I shall be fascinated to hear what they have to say about it.'