I know there are several that have used Transfer Factor in the past to help kitties that have been diagnosed with cancer. I may be facing this diagnosis with my dear heart kitty, Morgan. Here is the thread dealing with that. I am looking at purchasing some Transfer Factor and am wondering which formula people have used with the most success. I have been going back through some of the older threads, especially where it was first introduced here to EmberaldGreen. I think that Transfer Factor Plus was recommended over some of the other formulations. My question is did you/are you using the human formula or the feline formula? I saw a note on one of the sites that sells both that for sick kitties many recommend the human formula over the feline. I'm just trying to see what I should order.