Judge Mr Justice Timothy Kerr told the pair: “No sentence in a case such as this can undo the damage done, nor assuage the grief of the bereaved.
“You have both lost your beloved son.
“The wrongdoing that led to Daniel’s death must be punished, and it is my mournful duty to see it done.”
Greater Manchester Police Det Sergeant Mark Evans said Daniel’s death “left a permanent mark on everyone involved”.
He added: “Daniel was a bright, curious little boy who had grown up around dogs, but as a toddler, he couldn’t understand the risks they could pose.
“What happened to him was deeply tragic and I want to thank the teams who worked tirelessly to bring justice for Daniel.”
At their trial in July, the couple were cleared of Daniel’s gross negligence manslaughter.