What I wrestle with myself is how much of the proven techniques to use. Farrowing crates are a good example. Farrowing crates are used to confine the sow at time of birth until weaning.
No part of a farrowing crate is easier than a pastured pig. On pasture the pigs roam around, get their own food and water, and you can have a single giant feeder that holds a ton or two of food at a time -- so you only have to feed the pigs every other week or every third week.
With a farrowing crate there's quite a bit more labor. You're having to check food and water daily; the feeder is smaller, and needs to be filled more often. Because of the confinement you'll need to clean the area under the crate often, or put it up on grating so that the waste drops through.
Why go to all this trouble?
That's a whole litter I lost because the sow chose to have her litter in icy mud. She had a clean shelter with hay in it that I'd set up and gotten her into, but she rooted out of it and went to a corner of the pasture and I got a bucket of dead piglets. That sucked a lot.
If they make it out alive, there's a risk that they'll be squished by mom rolling over on them, stepped on (breaking their legs) or just wander out of the immediate area of mom. Last month I had an eagle take a newborn piglet. The world is pretty rough on piglets.
So in the interest of saving pigs, I'm going to adopt farrowing pens this year, for at least the first couple of weeks of the pigs lives. Other producers claim to be able to have lower losses than mine -- but I'm a little skeptical. For myself, I'd rather save their lives than hold that farrowing crates are inhumane.
A farrowing crate is only used at birth, and immediately after while the piglets nurse. It is not a gestation crate, which I believe are inhumane.