How do you generate a standard automatic e-mail reply ?

I run a rescue commitee for Bull Terriers for my local dog club. E-mail applications are forwarded to me from our National Hotline for families looking to adopt a dog that live in my state. I would like to have a standard reply e-mail to let them know that their application has been received and is being reviewed. Currently I have to type a legnthly reply to them and sometimes it is not very timely. Is there a way to do this?