An online petition has been launched to back using animals for medical research.
We want to know what your views on this subject are.
Do you think that it is ok to use animals for medical research if it could provide a cure for cancer or other terminal illnesses?
Or do you think it is unacceptable to use animals for any sort of research altogether?
If animals weren't used, how would you prefer medical research to continue?
E-mail and let us know what you think.
Unfortunately this topic is now closed but there are Comments pages on other subjects on the main Chat index.
I don't get how scientists who cruelly test on monkeys then moan how monkeys are getting endangered and blame us!
Arthur, 8, Ilkeston
It's better than doing it on humans! Although it is cruel to animals.
Alexander, 10, Colchester
It's pointless! Animals have completely different bodies to humans so just because they don't get ill, doesn't mean humans won't! We need to develop testing methods that are less harmful to innocent creatures. Government scientists must have thousands, if not millions, of pounds at their disposal. So why can't they develop a kinder way of testing?
Laura, 13, London
I think it is cruel to use animals for medical research but if my family were ill I would support it.
Hannah, 12, Birmingham
I think that using animals for medical research is cruel to the animals. On the other hand you could find the cure for many illnesses.
Devon, 11, Birmingham
I think that as long as the amount of animals used is kept to a minimum and it is for finding cures for terminal illnesses then it is OK.
Alana, 13, Crimchard
It depends on the animal you are using. If it's a mouse, fair enough but if it was a monkey that is cruel.
Sam, 11, Burton-upon-Trent
I know it's not fair on the animals but it may not result in death and we could find cures for animals in the process. And if there are more humans then there is more people to help animals.
Michelle, 11, Newton
Cosmetic testing: inhumane and cruel. Medical testing: a necessity, although still cruel.
Louise, 15, London
I'm 100% against it. It is ridiculous. Humans are totally different from rats, mice, hamsters and many other animals. Things that may cure/harm them may not necessarily do the same for us. They way they treat animals are in some cases horrific. Stop it now, before any more innocent animals are harmed.
Lorna, 14, Waterlooville
I think testing is wrong!
Emma, 13, Newcastle
If scientists care for people so much, why do they have such a disregard for the welfare of animals? The least they could do is give the animals that save our lives better cages/habitats and test less often.
Sarah, 15, Bristol
I think that it is a shame for those who have relatives that have cancer but it is very unfair to test animals. It's like saying if they are ill we should test humans - it's just not right!
Chantelle, 13, Tullibody
I think it's OK to test on animals but only if it benefits people with serious illnesses such as cancer. Animals are important too but they have shorter lives anyway and their feelings aren't as developed as ours anyway. But I think that if it's for cosmetic purposes it's totally disgusting and just wrong. I have mixed feelings about it, having two guinea-pigs but also relatives who have and have had cancer.
Eve, 11, Normanton
I think that animal testing is a horrible fact that goes on in the world. It should be stopped and there should be alternatives used instead.
Lucy, 13, Cardiff
I think it's preferable to using humans, because we've seen what can happen to humans with the whole 'elephant man' thing. And what harm is a couple of dead mice going to do?
Viki, 15, Bristol
Animal testing is wrong, wrong, wrong! Its evil and its not fair because lots of animals die and are forced to suffer and live a miserable life. Stop animal testing!
Jennie, 14, West Sussex
I know it's cruel to animals, but I'm not totally against it. If they keep researching, they may find cures for diseases and people who are ill need them, so no I'm not really against it, though it is a shame, that animal die in the procedure.
Nosheen, 13, Accrington
It's awful. Harming one thing to stop the harming of another, what's the point? There needs to be a better way so nobody gets hurt, including animals. Animals are friends, not foes.
Carli, 13, Middlessex
Although I think that it is terrible that animals are used in research, only two mice and half a rat are used for every person in the world for their entire life, so it doesn't seem that bad. I think that testing for cosmetic products is pure evil, but luckily it is illegal in the UK.
Ellie, 13, Surbiton
There must be a way to test medicines without animals, and animals don't have voices, so they can't tell you how they feel.
Sophie, 14, East Sussex
I don't know what to think because I love animals and I don't think it's right to test on an innocent creature. But when those 6 men signed up to be tested on for a new drug and one of the men now faces a life without fingers or toes, who else would you be able to test on so that people don't die? I mean animals are the next thing to people....but I still think it's wrong!
Natalie, 13, Belfast
In a way, yes. You never know what cures you might find... but it might not be the right one or how do you know what the drug does?
Angharad, 15, Wales
I think using animals for medical research is evil and disgusting. No one wants to be locked up and have medicine that could kill us shoved down our mouths. But on the other hand it does save a lot of people's lives but animals may lose theirs.
Sophie, 13, North Wales
I think it is an ok thing if the animals are treated fairly. Cosmetic research is stupid and pointless but medical research can help save millions of humans.
Kirsty, 15, Surrey
I think that using animals for medical research is all wrong! I don't think it's very fair for animals to suffer just because of the needs of humans.
Nicole, 12, London
If it was a case like Jodie said then I would support it but if it was for cosmetics like make up and bath products then it'd definitely bad.
Grace, 12, Saltburn-by-Sea
I think that it's not right. animals don't test on us so why should we test on them? Humans have a choice to be tested on, animals don't and animals have different reactions to humans.
Jasmine, 15, Brighton
I have mixed feelings about this. I think it's wrong for animals to die, but one dead mouse could save millions of people!
Hailey, 10, USA
I can't decide because it is unfair on the animals who want to live a free life however it still helps humans get better.
Eleanor, 11, Birmingham
I would definitely support it, because it means we can find a cure more easily without making humans ill.
Lettie, 9, Norwich
I don't know - if it doesn't harm the animals then it's ok...but I still don't like the idea of keeping animals to do tests on, what if they died?
Bex, 12, Birmingham
My mum has cancer and if using animals for medical research could find a cure, then I would support it.
Jodie, 13, Glasgow