No, it's not a sad shot. These dogs are unconscious, not dead. They're stray dogs in Bangkok, and vets have given them all vasectomies. It's an attempt to lower the number of stray dogs - while letting the current strays maintain their swinging lifestyle, I suppose.
It's weird that they're sterilizing them without neutering them. Maybe that's just quicker and they don't have to recover? Maybe they want the dogs to remain sexually active but sterile? I don't know.