Yeah, for adoptables and users that have multiple tables, each is linked together with another with a reference field that contains the same information. If this information does not match, you wont see the adoptables from adoption center, or users from members list.
This usually should not be a problem for anyone of you, unless you have a habit of resetting id increment from phpmyadmin. The below screenshot shows you how you can do this:
The highlighted field increments by 1 whenever you insert a new row into database, and wont decline even if a row is removed. Theoretically the id increases by 1 after you create a new pet, and it stays at the current pointer even if you hard-delete a pet. I am not sure how you can have id mismatches unless you've done more than creating/deleting adoptables in ACP.