With the Giraffe's is there a certain time the get feed or can we feed them at any time ?

You must purchase an encounter ticket. They sell out quickly.

You must purchase an encounter ticket. Early in the day is best since they sell out. The feeding happens at set times. Saturday's, Sunday's, and Holliday's at 11:30am, 1:30pm and 3:30pm.

They have a fixed time when you can feed the giraffe.

Not sure about that, got there at about 12 ish and they were going in to eat