Yes, it's enrofloxacin. The strength may be different, other ingredients are often for palatability, stability, shelf life, etc, so can vary. There are lots of reason to choose a certain kind/brand. Could be cost consideration (generic), ease of dosing or administering, best form for whatever you are treating, availability, etc. That is a decision your vet made based on circumstances so can't say why they used that particularly. If your Baytril is unopened it likely has a long shelf life ( 4 years unopened) so just keep it on hand. If it's opened then the shelf life is reduced to about 3 months.so this is a form of enrofloxacin but could have some different ingredients due to it needing to be refrigerated? So it possibly could not be the same Baytril I have that I got online?