Bhapimama
Songster
You definitely should!
It's not only a very kind thing to do, but it's also extremely rewarding, I'm loving it!
I don't want to elaborate on the details of what I've learned about the chicken industry as it's too depressing, but the main reason is that they have a few months of decreased egg laying, which they use as en excuse to kill every single chicken and clean out the shed (yes, they don't clean properly for 1.5 years) and fill it with new chickens. The meat isn't good enough, so they are either thrown away or end up as pet food.
My last rescue chooks were carried out by their legs to my contact person four weeks before they killed the remaining 21,000.
It's worth mentioning that this particular factory was about to get the SPCA's certificate as free range, as they were planning on opening a door at the back leading out to a mud plain at the back of the sheds. The number of chickens who would actually make it out into the mud would have been symbolic at best.
So yes, I only saved 4, but they have a wonderful life and it's better than none at all!