So to summarize everything posted on this thread, animals might be able to detect when you are high just like cancer.
when me and my friend smoke in my basement my cat always starts meowing really loud and clawing at the door to go outside, its really annoying when you are trying to blaze and relax and your cat is knocking shit over to get outside.
One of my kittys were following my brothers and I to our smoking spot, and we're smoking a blunt. The cat is meowing because she wants the attention. So I pet her and pick her up, my brother blows smoke at her and she freaks the fuck out like "AHHH WTF IS THAT!" And runs off. :[
I think my dog has been baked more times than my Best friend has and hes been smoking for 3 years. Every time i start packing a bowl, or rolling a blunt my dog comes running and waits then when i get up he follows me everywhere till i light up. its pretty awsome. I have a stoner dog.