I was told that this is a pretty good shot to use for pink eye if you catch it early. My question is, Is this a one dosage shot or do you normally give it for 2 or 3 consecutive days? It really doesn't say on the label. It seems like it might be a single dosage shot because for a 1200 pounder is calls for 54 cc's that is a big dosage (or at least it seems like it). If you have used this please give me some advice. thanks!