there are no dogs in this game, i don't know why someone voted yes. there are bipedal robots that are *called* dogs, but they don't look like dogs at all.
an iv is inserted into tomorrow's hand when she's being excavated from her sarcophagus- the cutscene it's is long and the injection isn't until the latter half of it, so it can be skipped very safely. no needles are used in the rest of the game.
Special chiral spiders in the first forest section of the game (Chapter 1) at the least! They do not harm you unless you attack/step on them first, if you do they swarm