As the puppies swarmed around you, you felt your body becoming smaller as fur started growing along your body. Golden fur started to grow along your arms and legs as your body started to change. You felt hot and itchy and on instinct more than anything started pulling off your shirt as your fingers started to become stubby, revealing that golden fur was growing up your body as your nipples began to swell a little and new bumps started to form along your stomach.
You felt the puppies start to press against you as your pants loosened and you pushed them off, revealing your shrinking penis as it formed into a vagina. Your arms and legs became equal length as they ended in paws, the golden fur covering your body by now. The transformation finally ended as your ears became triangular and floppy while your mouth and nose pushed out. New nipples had formed along your front as a tail finished and you wagged it as the puppies started to suck at your teats with milk filling their little bellies.
You nuzzled the puppies a little as they drank from you, they were your puppies, your instinct told you that. You couldn't remember your old life, all that was left was a beautiful golden retriever bitch.
"Ah, perfect," the attendant, your new mistress, said as she walked in and gathered up your clothes before petting your head. You wagged your tail happily from your mistress' attention. "Good girl, I was afraid you'd fight it more. Now we've got a brand new breeding bitch, do you want to have another litter?"
You barked happily at that as you felt the heat in your vagina. You wanted to be filled, you wanted to carry puppies again, that was your purpose in life after all? You licked her hand as she scratched behind your ears.
You were a good girl, and you were happy to serve your mistress.