that she was "devastated".
The woman, who asked not to be named, said little Shadow was treasured by two children aged 6 and 8.
I was there when she was born and I watched her grow up and learn to walk and run. She didn't know anything else but love
Shadow's owner
She added: "I was there when she was born and I watched her grow up and learn to walk and run.
"She didn't know anything else but love.
"They had only had her five weeks and they all absolutely adored her and he comes along and beats her to death."
Police were called on April 3 to an address in Oxford where Gerken had caused serious injuries to the puppy - who belonged to a woman in her 20s.
Gerken was arrested on April 4 before being charged the following day.
BEAT HER FOR POOING INDOORS
Oxford Magistrates Court heard that Gerken, of Woodfarm in Oxford, had become angry with the puppy for not being house-trained and tearing up belongings.
He started repeatedly hitting the dog with a slipper and refused to get help for the dying puppy as she struggled to breath.
Gerken then sent sick voice clips to Shadow's owner saying the puppy had "s*** everywhere."
He added: "I have just beat it from one side of the room to the other.
"I don't give a f***. That is how it will be with me.
"She ain't gonna do that again because she cannot f***ing walk."
PLEADS GUILTY
Gerken previously denied charges of causing unnecessary suffering to a protected animal and sending malicious communications.
But he changed his plea to guilty at the last minute on Friday.
Sentencing Gerken, magistrates told him: "The dog died as a result of what was done to her.
"You were determined to cause harm and you made threats that you would cause further harm to the dog.
"You were in a position of responsibility. You used a slipper as a weapon.
"You did not call or take the dog to the vet or seek advice even though you were aware she was unwell."
He was sentenced to 23 weeks in prison and ordered to pay £250 compensation, £1,000 in court costs and banned from keeping dogs for 10 years.
Heartwarming moment little boy cries tears of joy after opening box to find his parents have got him a puppy
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