First of all, you need to know the strength of the enrofloxacin (baytril) the vet gave you. there's different strengths , I am not familiar with 2.27 % I would have to know the mg/ml.

That would most likely be 10 mg per ml or 20 mg per ml then you could calculate what the dosage for your snake is, for each individual. the usual dosage for URI is 5mg per kg (1000gr) or 5mg/kg for injection, but it has to be higher if given PO (by mouth). Usually the dosage doubles when given orally because the body absorbs less of the medication when taken orally than when taken injectable. So, if you are giving the meds by mouth the dosage would be 10 mg/kg.

I'm a vet tech (not reptile vet tech) but I own snakes (not ball pythons) so I decided to sign up for this forum to answer your question. My 20 lbs Colombian boa is about 9 kg, if he needs 10 mg per kg, he needs 90 mg, if the baytril is 10 mg per ml, then he needs 9 ml of baytril. And just before I forget, baytril is administered once daily, so every 24 hours. that's what PO SID means. By mouth once daily. Hope this helps.