Natural Farrowing Pen For Our Pigs

We've got a few litters of piglets due soon so we made some natural farrowing pens for them. The pens are 8 x 8 with bumper boards running along the sides. The pen is used to keep the piglets safe and warm until they grow enough to go out into a group pen. The farrowing pen is only used for the first 10 days or so, after that the piglets are capable enough they can have more space.