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 moving parts.
Easy to Do-It-Yourself.
Automatic Pig Sorting.
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.