Code of Federal Regulations Title 9. Animals and Animal Products § 9.89.5 Feeding pens

(a) Stock pens and other enclosures for feeding, watering, and resting livestock in transit should have (1) sufficient space for all of the livestock to lie down at the same time, (2) properly designed facilities for feeding and watering the livestock, (3) reasonably well-drained, clean, and safe floors of concrete, cinders, gravel, hard-packed earth, or other suitable material, and (4) suitable protection from weather reasonably to be expected in the region in which the pens are located.

(b) Care should be taken to protect livestock unloaded en route at a point having marked difference in temperature from that at the point from which they were shipped.