Feed for pigs but not for calves

I am looking for a way to feed supplemental grains to 5 feeder pigs on pasture without allowing the cows (or calves) to get any grain.

This is my first time raising pigs on pasture. I am planning on running them with the cows on my dad's 35 acres of pasture. The cows are moved nearly every day and back fenced. While I have heard that it is possible to move pigs and cows together, I am concerned about the cows eating the grain. My parents market their cows as 100% grass fed. Does anyone have any ideas about how I can create a sub-paddock for the pig feeder that keeps the cows out?

It seems that a single wire could keep the cows out of the pig feed areas. However, I imagine that the calves would still have access. Is there enough of a height difference between calves and pigs that would allow for an electric fence option. Is there some kind of gate that would exclude the calves?

I would imagine a creep feeder of sorts would work fine. And be a bit tougher than one wire which sometimes isn't near enough to keep out a cow bent on grain!

How big the pigs are and how small the calves are would dictate if calves could get into the grain or not. But a pig averaging 2 - 3 feet tall can easily fit under into a creep feeder that an older calf would have issues with. And young calves that may fit under easy wouldn't be as interested in grain. Still, the determination of some cattle to get into grain can be legendary and it may be high enough for older calves to try and crawl in so if it were me, I would add an extra rail about a foot out from the gate at the same height as the bottom. Making a 3D entry point, more or less. This way calves wouldn't be able to just bend down a bit and get under, but would be forced to crawl that foot. If this makes sense to you in my jarbelled words!

Rooter door
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