A university experiment in which greyhounds were suffocated, revived after having their hearts removed and reinserted, then euthanased has shocked animal rights activists.

The experiment, conducted by Monash University and revealed by Humane Research Australia, aimed to test how well hearts can be preserved before organ transplants when the donor has already died.

Belinda Oppenheimer with her rescued greyhound Tobias. Credit:Arsineh Houspian

The research paper, seen by Fairfax Media, says the greyhounds were anaesthetised for the entire process.

But animal activists have dubbed the experiment "shocking" and questioned whether researchers learnt anything that could be applied to human surgery.