I agree with the use of guard rail or heavy rough sawn boards for the outside of the corral. Space posts closer than you would for a fence. 6 ft or 6'3" (?) for guard rail std hole spacing. Guard rail or heavy boards limit their view outside. Build it high enough.

One of Grandin's key points and the reason for the curves. is controlling the visual environment for cattle. I totally agree with this. I have some pipe gates in several places in the corral and found that if I wired some plywood to the inside of the gates so they can't see out they stay a lot calmer while working others in the alley and chute nearby.

As far as posts go you can check with your local electric or telephone utility to see if they have any used poles. My outside posts are all used rural power poles. Use the best bottoms for the corners. I throw in a bag of dry concrete at the bottom when setting them in the augered hole.

One of the simplest and looks like it would be very useable corrals I have ever seen is right behind a rest stop on I-29 S near Brookings SD somewhere. Guard rail on RR ties with a simple interior about 30" clear (Grandin's number) alley along one side and into a corner also made of guard rail with about a 20 ft straight section with the lead in tapered out wider (to about 10 ft?) with a swinging solid board crowd gate on the lead in end post. You could back a portable chute right up to the alley outlet. Also had a gate at each end and the way the fence came up to the alley outlet you could use it to sort/wean etc by directing cattle into 2 or 3 different pasture sections. I must have spent an hour at this rest stop last year before building my own corral.

Guard rail is going to cost money but as other have said it will last a long time. RR ties or telephone poles are going to cost money or time but a corral is one thing that is worth doing right the first time. jmho based on recent experience.

Jim at Dawn

Autistic kids tend to be very influenced by their visual environment - things around them (we all are to a certain extent but much more so for the autistic). The autistic need plain walls, minimal distractions, etc. I think this is one way Dr Grandin's autism fits in with cattle because the cattle seem to be very influenced by light, movement, noises and other visual stimulus also. Solid panels and curves tend to minimize the visual input that can set them off. That's also why she suggests oiling or greasing any moving chute parts etc that may be noisy before working cattle. I think she has some very useful insights. She says the calmer you can keep them especially prior to slaughter the less adrenalin etc they release and the better the meat will taste.

The $5 poop effect - this reminds me of a ranchers description of the $5 poop. He said if you can keep them calmer they will drop less manure in the working area than if they are all riled up. He said each manure patty weighs about 5 lb and is 5 lb less you will get paid for on live weight. I am just passing this one on....!