The valorization of poultry byproducts, like feathers (processed to feather meal), in animal feed could contribute to the presence of veterinary drugs, including antibiotics. An animal study was carried out to study the fate of sulfadiazine, trimethoprim, and oxytetracycline in feathers, plasma, and droppings of broiler chickens. Cage and floor housing, different from current farm practices, were studied. Samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A longer presence of antibiotics was observed in feathers compared to plasma, with sulfadiazine being present the most. The internal presence (via blood) and the external presence (via droppings) of antibiotics in/on feathers were shown. Analysis of