Public opinion has always been divided on the subject of conducting experiments on animals. Although the supporters of this put forward some compelling, I strongly believe that experimentation on animals should be severely forbidden.
The most important disadvantage of experimentation on animals is that animals cannot express theirs fillings when they are tested. Experiments can harm this livening organisms. In extreme cases - even lead to a permanent damage or even death.
In addition to physical damage, the experiments can lead to mutations of species. It is very dangerous, not only for animals, but also for people who live in the neighborhood of mutant animals.
An additional disadvantage of conducting experiments on animals is not the total effectiveness. Although the animals respond in a similar way to the people, will never be 100% sure that the tested (for example) cosmetics will not hurt a human.
Finally, why people use experiments on animals, when we know another methods check whether a product is harmful? This is nothing other than politics! New products, that usually are tested on animals, not used for customers, but for producers, who have a big benefits with this products.
On the whole, experimentation on animals are not irreplaceable and necessary. It is important to remember that there are other options to try products. As it was previously stated, I am totally against conducting experiments on animals and in my opinion this should not be permitted on humanitarian grounds.