No animals are actually killed during the movie but there are a few dead animal bodies show. One is a squirrel and the others are practically unidentifiable
Seizures are mentioned specifically to be a symptom of turning into a zombie. We see these occur in characters turning into zombies, and the POV of the main character turning into one.
A young girl and old man are kidnapped and put into separate cages as bait for zombies; later the protagonist is also kidnapped and put into a cage. Everyone gets out of the situation unharmed, although it is tense.
There are three incidents involving large needles that when injected in the temple, produces a large needle for to stop someone from turning into a zombie but also killing them. One incident has a woman testing the needle to show the needle point. The second is a man finding one on the ground next to his dead wife, seemingly used. The third is a man attempting to gather the courage to use it on himself, but is interrupted.
A girl cuts herself on the hand with a rock to lead a zombie away. Later, she hits herself on the head with a rock explicitly to make her emotional pain dull. She is stopped before it gets too bad, and has her head wound treated.