Pain Induced in Rats at Otago Uni

Pain Induced in Rats at Otago Uni


For the 10th day of our 12 Days of Christmas University of Otago exposé we are sharing a truly horrifying experiment that they conducted on rats.

A lot of rats are sadly used by Otago Uni — in 2019 alone, they used over 1500 rats and an additional 10,731 rats were killed by Otago, who were bred to be used in science but were never used/'needed'. This is just further evidence of their complete lack of respect for animals lives. 

In the gruesome experiment that we are exposing today, rats had a nerve in their leg surgically pinched to induce chronic pain. They were then forced to balance on a rotating drum, with an injured leg... 

The Experiment 

  • Rats were anaesthetised and the skin of one hind leg was cut open. With blunt instruments, the muscle was forced apart to get to the sciatic nerve. Sutures were placed around the nerve to give it a pinch. Constricting the nerve in this way was done to cause pain build-up.
  • The skin was stapled and they received 36 hours of pain-medication.
  • Some rats were given a synthetic drug to see if it could be used for pain relief. 
  • Their pain level was tested in two ways:
  1. Each rat was placed on a mesh surface in a dark room and his operated limb was poked with thin threads of increasing strength.
  2. Each rat was tested on a rotating drum where they had to walk against the movement at increasing speed from 4 to 40 rotations per minute; for 5min or until they fell off. 
  • The paper did not state the fate of the rats.

The rotating drum

The video below is an example of what the rats would have experienced when being made to walk on a rotating drum, the main difference is that the rats in the video are healthy. The rats in the study we are exposing had had a pinched nerve in their hind leg for 10 days, but still had to do all that balancing.


This was all done to try and test the effectiveness of potential pain relief medicine on rats. Chronic pain is such a complex issue that using the ‘animal model’ is not likely to teach us much. Inducing pain in a rat via surgery is simply not the same as humans who are experiencing chronic pain!


At the time of the study it was evident that there are better ways; for us and for the animals, yet Otago Uni still continued on with using outdated and cruel animal tests. 



  • Sign our petition aimed at ending animal experimentation: Help us by calling on the New Zealand Government to step in and start prioritising non-animal-based research methods and replacing the use of animals in science! The University of Otago is not going to make these changes on their own so, we are going over their heads and #StrikingAtTheSource!
  • Download our guide on the top ten ways you can help end animal testing in NZ.
  • Purchase one of our Christmas Gifts to help raise money for our important campaigns. 


  • Learn more about our 12 Days of Christmas campaign, which is exposing more cruelty at Otago. We will be uploading a new experiment that we are exposing to this page every day until the 12th December.
  • Find out why Otago University is at the centre of this campaign.
  • Access the the full paper we have exposed above on our references page.