A diagnostic and testing apparatus and related methods for the use of the same are disclosed which derive and use antibodies to equine albumin and equine hemoglobin in testing apparatus, kits, and methods for detecting and localizing gastric and colonic ulcers or bleeding in horses. Fecal droppings from a horse to be tested are placed in a container together with a buffered liquid solution and mixed thoroughly, following which several drops of liquid from the container are placed into a test kit. Visual markers in the test kits signify the detection of the indicators equine hemoglobin and equine albumin, which are respectively indicative of the presence of gastric and/or colonic ulcers or bleeding.