Auto Pig Sorter

Auto Pig Sorter Seen from Approach Perspective

Although we have multiple herd groups, for ease of management, water access, whey feeding and such we like to keep the pigs in large groups than smaller where possible. In the warm months this works fine because they sleep in small cohort groups spread out in the pasture. This natural division of pigs prevents crushing of smaller pigs. In the cold winter months the pigs tend to want to crowd more for shared body heat and more importantly everyone wants the best sleeping spot. To resolve that we setup separate sleeping areas for different size pigs. Then the trick is getting the right sized pigs to use the right sleeping areas.

White Pig Approaching the Auto Pig Sorter

We have a number of tricks including mazes[1, 2] and distance as well as size of openings. All of these work as solid state automatic pig sorting machines to use the pigs’s natural behaviors to put the right pigs in the right places.

The Red Pig on the Right Finds Itself at the Limit of the Hurdle

In factory farms they use computerized mechanical sorting machines to sort pigs based on weight. This achieves the same goal but at a much higher installation cost and maintenance cost. The fancy electronic and mechanical systems break down further increasing the cost. I like simple.

The way the system above works is quite simple. About as simple as you can get. There is a height board that sets the maximum height of the pig that is allowed through. Somewhat bigger pigs may scoot through but this is taken into account by the setting of the height board.

Tighter Sorting with Verticals

Adding vertical posts close together would further refine the size specification so that marginal pigs could not scoot through. This is similar to what is termed a “Man Gate” in stock yards and used for a “Dog Gate” for livestock working dogs. With a man gate the hurdle is at the bottom allowing long legged humans to step up and over. With a dog gate there is a hurdle dogs will jump and a top bar to stop goats for example. Sizing openings selects who can pass through the gate.

A hot wire on the outside of the creep keeps big pigs from simply opening the gate.

Creeps can be set to exclude chickens and other poultry invoking the third dimension making the box have a length. Chickens are not fond of going through a long, low dark tunnel. This allows one to create a piglet creep that keeps chickens out but allows piglets in – Useful if feeding a special feed to piglets that you don’t want the chickens to eat.

To the right in the top photo is a hurdle sorter. This is the opposite of the creep sorter. The hurdle requires jumping up and over. Little pigs hesitate at the hurdle, consider hurdle vs creep and choose the easy path, the creep. Big pigs go through the same process and choose the hurdle instead. By placing a hurdle next to a creep it creates a strong sorting.

The red pig in the photo is discovering how uncomfortable it is to try and go over the hurdle and in the future it will likely go the easy route through the creep on the left. Coming downhill it is easy so any small pig that did end up outside finds it easy to return.

An additional sorting mechanism in this case is that turning to the right leads uphill and then 1,000′ out to the greenhouse which is a long distance for small pigs to walk but big pigs are fine with that. Thus making the bigger pigs walk further and the smaller pigs sort off sooner from the path is one more refinement in the sorting mechanism.

No electric.
No moving parts.
Easy to Do-It-Yourself.
Automatic Pig Sorting.

For more automatic self-sorting mechanisms see the Chicken Innorator and the Pig Trap.

Outdoors: 32°F/24°F 2″ Snow
Tiny Cottage: 66°F/62°F

Daily Spark: Give the dog a bone. You think, there’s no way you can bite through that. Crunch, crunch, crunch like he’s eating potatoe chips. He swollows and askes for another. Nobody can eat just one. Watch the fingers.

About Walter Jeffries

Tinker, Tailor...
This entry was posted in Uncategorized and tagged , , , . Bookmark the permalink.

11 Responses to Auto Pig Sorter

  1. Andy says:

    Third paragraph from bottom where it starts To the right in the to photo is a hurdle sorter. The third line down ” choose the easy path, the cree. ” Shouldn’t it be the creep ?

  2. Peter says:

    “Pig pigs go through the same process…”

    ….assumes that there are other sorts of pigs like “chicken pigs,” “goose pigs,” “Tasmanian Devil pigs,” etc. :-D

  3. Farmerbob1 says:

    In a situation where a smaller pig, like the red pig above, that used the hurdle when too small and perhaps didn’t like it much. Would they be likely to try to keep pushing and forcing their way into the creep that they remember as easier to get into?

    I know pigs are smart, but I’m curious just how stubborn they are. Is there any risk of growing pigs injuring themselves trying to continue forcing their way into the creep, or do they make a decision on a trip-by-trip basis, and eventually decide to use the hurdle, without damaging the creep?

    • They make the decision on a trip by trip basis although pigs are creatures of habit to a large degree. It is not an absolute Either-OR type sorting. When they get to the either way size they sometimes go either way which makes the sorter have a grey area that works out nicely.

      Keep in mind that pig intelligence is greatly over estimated by people. They are good at things within their ken but not good at human or dog things. It is a different way, the way of the pig. Don’t expect a pig to be a cat. Hollywood and such groups confuse the public by training many similar looking pigs to each do one trick and then cutting the shots together to make a movie. This makes people think pigs are a lot more intelligent than they really are.

      • Farmerbob1 says:

        Yes, from what I’ve been able to pick up, here and elsewhere, pigs are smart in very limited ways (typically associated with finding food) but they do also learn to self-identify in mirrors as well, which puts them above a lot of other animals.

        Understanding how an animal thinks is an interesting challenge! I’m curious though, how often do your pigs do things that you simply did not expect, despite the years you’ve been raising them?

        • The self-identification was one of those tests that was in vogue for a while because humans thought no other animals could do it. But then many other animals have turned out to do it. The problem I see is that people try and think of other species as intelligent in some particular way, the human way, rather than accepting that each can be different in it’s own way. It’s all about evolution. As species we each have developed the tools needed for survival in our niches.

          At this point I almost never see the pigs do something unexpected, but then I have interacted with thousands of pigs in the natural setting of pasture where they can do a wide range of behaviors so I’ve seen a lot of behaviors. My observation is that pigs think about food, sex and where they get to sleep, in that order. They will learn to do mazes which fits with following forest trails, but can be confused, tricked, by certain slights of hand such as being able to see through somewhere they can not pass through. Much like how magicians take advantage of how people think to do redirection.

          • Farmerbob1 says:

            I’m not trying to trick you into saying that pigs are too smart to eat, Walter. I suspect you see some comments like that from time to time. Pigs are pretty fantastically successful critters though, and that success is impressive all by itself. Seeing what they are doing down in Texas with only humans to predate on them is eyebrow-raising. They are fascinating and remarkably intelligent-seeming, but the intelligence is still animal intelligence. Nothing like the elephants, dolphins, and some primates. Bacon is good. I wouldn’t want pigs to get smart enough where I’d feel guilty eating it.

          • The key is people tend to forget that intelligences are different in many cases. Pigs are good at pig thing. They have a herd mentality. It is non-cooperative but rather one of Solipsism. Cooperative animals developed different intelligences for working together. Each fits its niche. It is also worth bearing in mind that we selectively breed pigs for their ability to grow and produce great meat while we selectively breed dogs and humans for their intelligence and cooperative behavior. Thousands of years of this have resulted in improvements in both, within their own realm.

  4. Shawn says:

    Sounds like a fantastic DIY system. I would love to see some video footage of it in action!

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.