What would you sacrifice to push forward efforts to eliminate deadly diseases?

What about to make sure our products and medicines are safe, especially for our most vulnerable?

These questions lead us to ethical quagmire surrounding the use of animals for research, testing, and experimentation.

Some of you shared your thoughts with us.

This is Kate in Vermont.

Animals do not exist for the purposes of people, to cure them, to heal them, to prevent them from getting sick or injured.

I think the fact that labs still experiment on live animals,

especially dogs and cats, is abhorrent, and it needs to be stopped.

Humanity should have evolved enough by now

to not make other animals suffer for ourselves.

This is Judy Ingram from Rancho Cordova, California.

I'm so tired of hearing about experiments done on rats or mice

mentioned so casually and with no concern for their pain.

Long ago, Cardinal Newman said about animal experimentation.

He said, there is something so very dreadful in tormenting those who have never harmed us and who cannot defend themselves and are utterly in our power.

Thanks for those messages.

We've long heard the term lab rat.

It's an expression of understanding that animals are used in scientific spaces.

Although rats are the most widely used animal, they are far from

the only one. Around 40,000 dogs were used in labs last year. That's according to a leading advocacy

group. The most common breed used are beagles. Journalist Melanie Kaplan adopted Hammy in 2013,

a beagle who had been used for research for nearly four years, and it led her to a

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