A gourmet cat food sparked an outbreak of a deadly strain of tuberculosis which affected around 50 animals and at least two of their owners, veterinary scientists believe.

The “natural” wild venison cat food was recalled nationwide by Natural Instinct, which marketed it as a healthier option to regular pet food.

The move came after veterinary scientists at the University of Edinburgh began looking into why dozens of cats had been struck by bovine tuberculosis (bTB).

The issue first came to light when six cats were taken to separate vet practices across England.

Tests confirmed they were infected with bacteria which usually caused TB in cattle, but can also infect other animals such as rodents and deer.

A further seven cats living in the same households were also found to be infected.

All of the animals were indoor cats, meaning they could not have been passed the infection through contact with wildlife or livestock.

The one thing the cats did have in common was that they had all eaten Natural Instinct's wild venison product, vets at the University of Edinburgh’s Royal (Dick) School of Veterinary Studies found.

Professor Danièlle Gunn-Moore, of the University of Edinburgh’s Royal (Dick) School of Veterinary Studies, said: “We found circumstantial evidence that these cases of TB in cats were linked to a particular brand of raw food diet.

“Not all animals that are infected with the bacteria will develop disease but we would encourage owners with concerns about their pets to get them checked by their local vet.”

Natural Instinct, which recalled the product last December, stated on its website that it stopped selling the product immediately after being informed by the Food Standards Agency “of the problem of lack of inspection”.

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A spokesperson for the company added: “We can assure our customers that Natural Instinct followed, and continues to follow, every food standard, hygiene regulation and best practice required to produce raw pet food in the commercial market place.

“Even though we no longer manufacture and sell the venison cat product, we are continuing to work with the Food Standards Agency and all necessary organisations. Not only as part of the investigation into the venison cat food product, but to ensure the highest standards continue to be met across the industry.”

A report on the first six cases is published in The Journal of Feline Medicine and Surgery.

Since its publication, the outbreak has continued with researchers receiving reports of cats with bTB in 30 households across the UK.

One hundred people and 90 felines have been referred for tests.