Animals in the Lab

Banting performs a surgery on a dog in 1921.

“On that same day, Dog #410 was the first to receive an injection of the pancreatic extract. After being given four cubic centimetres (cc) of the extract, the diabetic dog’s blood sugar percentage level fell from .20 to .12 within an hour. Based on tests of thirty non-diabetic dogs Banting and Best worked with, the average blood sugar percentage level was .090. They gave Dog #410 another injection, but its blood sugar measurement barely moved. After a third injection, the blood sugar level rose. The dog was given some sugar in water and then hourly injections of extract, but with no apparent effect. The next morning, they found the dog in a coma, and it soon died. Nevertheless, the results of this first extract test were encouraging, as it seemed to have a marked effect.” 

Read more — Banting & Best: Progress and Uncertainty in the Lab

Dr. Frederick Banting and Charles Best conducted many experiments on dogs during the summer of 1921. In order to cause them to become diabetic, they would ligate the pancreas and then administer their experimental doses of insulin. Later in the process, other animals were used (including rabbits and cattle) to help purify insulin and ensure manufacturing could meet demands.

It’s hard to imagine these experiments happening today: dogs are family pets, after all. The use of animals in science is strictly regulated today and can be an issue of heated debate.

We have curated two articles to help guide classroom discussions about animal experimentation and act as entry points for learning if students have questions about why Banting and Best conducted their experiments with dogs.

The Moral Status of Animals in Science, by Dr. Katharine Browne

The Ethics of Medical and Scientific Research Involving Animals, by Dr. David Hanwell