OXFORD University has claimed it would take more than 18 hours of research to calculate how many animals have died because of animal testing at the institution.

The university cited guidelines on research time when failing to respond to questions in a Freedom of Information (FOI) request by the Oxford Mail.

A spokesperson said: “We are transparent about our research using animals.

"Our website shows the annual totals of all scientific procedures involving animals, after which they will normally be killed humanely under Home Office rules.

"Research procedures involving animals vary greatly. They include the breeding of genetically modified mice, which makes up the large proportion of scientific procedures. Surgery only accounts for a small minority of procedures.”

The university says more than 236,000 animals from at least 12 species were used in ‘procedures’ in 2017. Of those, 2,202 were used in ‘severe’ procedures.

In 2017, 35,777 mice, rats, frogs and zebrafish died before being used in procedures, despite being bred for that purpose, according to the university.

However, the university did not clarify how many animals died due to testing.