- Some effects of testing on animals are blindness, burns, mental problems, and death.
- Experimental drugs can cause unexpected harm to the animals, and once the experiment is over, they're often killed.
- The animals are kept separated in small cages, which doesn't allow them to make natural choices.
- Studies show that mice can feel empathy, which can be very stressful when they hear distress calls all day.
- Animals are not exposed to fresh air. If they're lucky, they get to go outside for a few minutes and are rotated, so once they go out once, they probably won't get to go out again.
- The fact that they're indoors in a windowless laboratory all day means that they don't get natural sunlight.
- When the lights are on all day, it can cause stress because it's not natural and disrupts their sleep pattern.
- Being around loud noises all day can also be very stressful because their ears are much more sensitive than ours.