As you can see the device in the video has only small spikes or nubs on it. This is a more modern design that is currently in use for calf weaners. This type does not allow the calf to feed from their mothers because they cannot look up and put anything in their mouth due to the calf weaner blocking the path. It still allows them to eat hay off of the ground however, due to the direction the device faces when the calf looks down.
The model that we showed was a much older model and worked by poking the mother when the calf tried to suckle. She would kick the calf away sending a signal that they were not allowed to suckle. This sent a pretty clear message to junior that mom was not going to allow that thing near her. After wearing the calf weaner for a while the calf quickly learned to eat hay and other more adult forms of nutrition and the device would be removed.
Both models are available for purchase and are extremely cheap, under $5. They are now mostly made of a hard plastic instead of metal. These can be picked up at any local farming supply store or online through a multitude of vendors. Some modern ones look like these.
Keep checking back for more mystery artifacts, and stop by in person to get face to face with some of these fascinating artifacts!