Did you get the Qwiko Avian Probiotics? If so, then it comes with that little scoop, which is the correct "dosage" that you sprinkle on/mix-into her food...When it comes to Probiotics they aren't actually "dosed" like a medication is. They are simply strains of different healthy Bacteria that normally lives throughout their GI Tract, and there are literally millions/billions of cultures in one of those little scoops. So they assume that the bird is not going to actually ingest that entire amount. She just needs to get some of it into her GI Tract once every day, and the live-cultures grow from there.
If her main staple food is seed-mix, it's actually easier to dose them, because if you mix the Probiotic powder well throughout her seed-mix, it will "dust" or stick to all of the outer seed-shells, and every time she puts one of the seeds in her mouth, she's taking in some of the Probiotics. This isn't an "exact" measurement or dosage like with an actual medication, as again, these are living bacterial strains that are going to grow daily inside her GI Tract, so you're basically just adding and replacing them every single day. And that tiny little scoop of the Probiotic powder literally contains billions and billions of bacteria. So as long as you're giving her one of those full, pre-measured scoops and mixing it well into either her seed-mix or if she eats rice every day then that would work great too, even if she doesn't eat it all, she's getting more than enough to keep the healthy bacteria continually growing throughout her GI Tract.
