Yeah; I grew up as something of a dog person and liked/loved our general property dog plus my father's hunting dogs (short haired pointers, about the nicest breed in the world) that I took care of ... but within a quarter century or so I became allergic to dogs in general (not sure why, having had terrible allergies all my life).

This sort of thing sounds like something you could make work in special cases but could fall apart in all sorts of ways. E.g. I show up to interview at your office (at which time I'd immediately start reacting), and I'd have to say sorry, I like the office dog(s) but I can work here only if you banish them and seriously clean the carpets....