A kennels has undergone checks after a dog was diagnosed with a contagious deadly disease.
The West Drayton pound is used by the Metropolitan Police to care for breeds which are banned under the Dangerous Dogs Act.
But after the animal, which was wrongly suspected of being a banned breed, was returned to the owner, it was diagnosed with parvovirus.
An Met spokesman said: "The kennels have very experienced staff and each kennel hand has direct responsibility for a number of dogs.
"This enables the staff to get to know the dogs more intimately, and therefore any concerns about their welfare can be dealt with at the earliest opportunity.
"The care and welfare of the dogs seized whilst in our care is paramount to the Met and the kennels where they are cared for are of the highest standard."
Parvovirus causes bacteria to enter a dog's blood stream and often results in death.
The Staffordshire bull-terrier, whose owners live in Acton, is not expected to survive.
The Royal College of Veterinary Surgeons have inspected the kennels and confirmed that recommended procedures, including vaccinations, were in place and kept to.
The spokesman added: "The owner of the dog has been contacted to reassure her that the kennels are of the highest standard and action will be taken following the possibility of the parvovirus being present."