Nigerians gestation averages 146-152 days, we have never had a doe go over 150 days. She will bag up before she kids, The ligaments in her tail will loosen until her tail falls over and she will not be able to hold it up. Some signs things are close are her losing her plug, which is a white bit that she will pass, about this time she will start making her place (nest we call it) to have the kids, a corner, somewhere draft-free usually.
The DW makes up a bag to take to the barn, old towels, a garbage bag, newspapers.
When the kid(s) come, if your out there, help her clean them off. Offer her some warm molasses water. She WILL drink it, after and in between kids.
After she is done birthing, you will want to try to make sure the kid(s) each get some to drink from the mom. Collostrum is very important for them to get as soon as possible.
clean up what mess you can and toss it in the garbage bag, I know nature makes it so the mom will do this, but, she is a farm animal, not out in the wild.
* - rubber gloves and k-y (lets hope this is never needed) but sometimes it is. at this point you will want to call a vet if you have not already. For if you need to assist (inside) to help the kid get out, she will need antibiotics to keep her from getting an infection.
** Amniotic fluid from goats smells like kitchen sponges you buy in the store when brand new **
