When I purchase tickets online, can they be used any day of the week? Also, can tickets be bought at the gate or is it online only?

They can definitely be used any day but tickets along with feed bags can be purchased at the entrance.

They can also be purchased at the gate. The online tickets are not dated when you purchase.

Can be purchased at the gate

Any day and can be at the gate.

Correct, any day and at the location.

Yes any day and may be purchased at the gate.