are probiotics good for dogs?

Penny's been prescribed doxycycline for her cough, so I wondered whether to give it with food. A site about human medications says having food in the stomach makes it less effective, but a dog-related site says always give it with food. Why does life have to be so complicated?

I'll play safe and give it with food.

Antibiotics destroy good bacteria with the bad, so when I take them myself, I use probiotics. I think I'll look around for a dog probiotic.