The pills have 25mg in them, which is the same as.25ml (cc) of the 10% liquid that poultry people seem to buy most often. The vets I have used have all said to use 15-20mg/kg for five days, so how much one gives would depend on the weight of the pea. To give it to them, I would stick it in their mouth and make sure they swallow it.
Unfortunately, these pills are way more expensive per mg than the liquid. For example, using the numbers above, a 6kg peacock would get 4 or 5 pills a day for 5 days, that's almost the whole small bottle!
The only upside is that the pills *might* have a longer shelf-life than the liquid.
Personally, I buy the injectable and give it orally or subcutaneously to poultry and subcutaneously to cats.
For those looking for to buy injectable, try searching the web for enfloxil or enroxil, it's generic Baytril that's made in outside the US.