A police dog will not be allowed to retire with her handler despite a petition of more than 35,000 signatures.
The campaign to keep Sgt David Evans and police dog Ivy together received support from people across the world.
But West Mercia Police chief constable Anthony Bangham said it was "in the best interests of the dog and the force that this request is not met".
Mr Evans' daughter Jennie said she would not give up the fight.
The family, from Market Drayton, Shropshire, launched a petition saying the officer was "heartbroken" at the prospect of not being able to keep Ivy when he stepped down after 34 years' service.
Ivy, a Malinois cross German Shepherd, is four years old. Police dogs normally retire at about eight.
Sgt Evans, of Market Drayton, had offered to buy Ivy and cover the cost of replacing her.
In a statement, Mr Bangham said he had met Mr Evans to explain the decision.
"We appreciate that all our handlers form close relationships with the dogs they work with and, understandably, many want to continue that relationship when they retire," he said.
"Sometimes at the end of the dog's working life we are able to facilitate this but we always have to consider the needs of the dog and the force at the time, and to meet our obligation to spend public funds wisely and ensure best value from all our resources.
"Although the dogs live with their handlers and have close relationships with them, they are not family pets. They belong to the force and are highly valued resources.
"Ivy is very young and has many years service ahead of her. She will therefore stay with the force and be re-handled with another officer."
Mr Evans' daughter wrote on Facebook: "We, as a family are utterly devastated at this news and also in complete and utter shock that this is the decision West Mercia have decided is best for Ivy.
"I am not ready to leave this fight and I will be looking into other options to try and change this outcome."