Water medication looks like the obvious choice when you run an intensive pig operation. Drop the antibiotic in, let the Dosatron handle the mixing, and walk away. No needles, no chasing individual animals down the pen. But there is a variable that rarely gets talked about, and it might be quietly wrecking your treatment plan before the drug even hits the pig. The Chemistry Issue Nobody Checks Oxytetracycline has been a staple in pig farming for a long time. It is cheap, broad-spectrum, and approved nearly everywhere for treating respiratory and gut infections through feed or water. But OTC has a habit that matters: it grabs onto calcium and magnesium…