Build a large whelping box for your expecting dog.
Step 1: Ideas
I build this box for my female German Shepherd so its good for big dogs. I don't have pictures of is construction ,but I thought this might give you some ideas.
It's 4'W by 4-1/2' L ft.
The framework is made of 2x4's and the sides are 3/4" particle board.(I didn't have any plywood so I used these pieces that were left over from our barn roof. The front is hinged and secured on the sides with hasps. Good luck!
If you have any questions, complaints, or ideas please comment below!