using a lower voltage ac/dc adapter such as a 12v converter so if you use say a 15v or a 10v = 10v slow 12v medium 15v fast ... fan speeds.......Looks like you're in an LG, too...? What kinda baby chickens?
I've read a computer fan moves too much air. I'm already at risk of drying out significantly with the humidity as low as it is here. I'm nervous about a fan. Not to mention the actual install of said fan. SCG and electricity don't mix. Just ask the emergency electrician.