For high key, it is easier to get a more balanced light with more
strobes. If you don't have them, you don't have them and you do the
best you can. You could have controlled blowing out the whites some
with a more even light(flat lighting isn't always bad with animals)
I usually use 4 lights for high key, and as few as one for a canvas
backdrop.
I like silver umbrellas for this sort of pet shoot. Gives you a more
specular light.
If you are going to use one light for pet shoots with a white
backdrop, I would suggest the light be more centered, vs off to the
side. Again, it is a flatter lighting, but, it is ok with pets(vs
people) When I do a fundraiser with many people coming through, I
purposefully make the light fairly flat as I just don't have time to
be fancy with it
If you would like examples of what I am talking about, I am happy to
post them up. I am no lighting master though!
--
Wag More. Bark Less
http://JuliePoole.com