David`s remarks are on the ball.
The sows probably mind very much if the crates are too small. Our sows are larger these days with the gilts bred heavier in order to defend that first-litter sow from a large and voracious first litter forcing her into a damaging condition loss at the end of lactation, which can affect her performance in the second parity – or even beyond. Prof. Colin Whittemore called it the `Nose-Dive` many years ago.
They probably mind very much if the flooring is harsh or worn, resulting in lameness and body sores. Lameness is the second commonest cause of premature culling after infertility.
They probably mind very much if the atmosphere is foul due to inadequate or poorly-directed ventilation, commonly seen in cold countries in winter, and when the slurry is allowed to accumulate only a few centimetres below the slats at any time.
Conversely, they must also mind very much when those breezy gestation sheds in the tropics expose a row of sows to sunburn on their rears due to insufficient eaves overhang or the lack of a precautionary shade curtain.
If only sows could speak. Then they`d tell us what they minded!
Meanwhile, managed as many are these days, they tell us indirectly in smaller and less viable litters, a shorter productive life, lowered immune response, more veterinary attention and higher labour costs.
There is not much wrong with the gestation crate designed, maintained and managed properly. But only a third of them are!