Cow magnets are used as a preventive veterinary product for Traumatic Reticula Peritonitis (popularly known as Hardware Disease). While grazing, cows eat everything from grass and dirt to nails, staples and bits of bailing wire (referred to as tramp iron) Tramp iron tends to lodge in the honeycombed walls of the reticulum, threatening the surrounding vital organs and causing irritation and inflammation, known as Hardware Disease. The cow loses her appetite and decreases her milk output (dairy cows), or her ability to gain weight (feeder stock).
Cow magnets help prevent this disease by attracting stray metal from the folds and crevices of the rumen and reticulum & hold them in place so that they cannot move around and injure the animal. The magnet simply keeps foreign metallic objects adhered together in a ball, reducing the chances of penetrating the reticulum. They can be administered with a balling gun,like those used for pills. The magnet will move into the second stomach compartment of the cow. It will usually remain there for at least a year,but may eventually be expelled through the digestive tract.