8 Chickens...can you fit them all in your car? Will each be in a carrier individually or with a friend?
Also think about take some extra absorbent bedding material so when they do poops in their travel carrier, it does not stink up the whole car...thinking 8 poops for 15 hours..
A few times I have drove 2 and one time 3 of my chickens 2 hours drive in the car which is nothing compare to 15 hours, they pooped a bit and I knew it straight away....
My experience was that they were each in a small dog travel box carrier, I had the radio on, I talked to them by calling out each of their name. On the way back, I did stop the car and give them some water each, they were all laying down in their travel box. I know they were tired when we get home.
If I was to drive 15 hours like you are, I would give them some vitamin drink the day before just to give them something for the long drive. They might not want to eat/drink while in the car.
Might workout how many stop you will make and how many chickens you let out to stretch legs at each stop, that sort of stuff.
Being emotional about my chickens, I would take my chickens with me when I move.
All the best with moving your chickens with you
