Custom Menu on Posts in say "dogs" Category?

Hi all,
Here’s the scene…

1) I have 3 categories – “dogs”, “dog foods”, dog training”.

2) I have 3 custom menus as follows:
Menu 1 = home | dogs | contact us
Menu 2 = home | dog foods | contact us
Menu 3 = home | dog training | contact us

3) When a user is on any posts in “dog foods” category, I want to show the menu 2 on the top.

When a user is seeing a post in “dog training” category, I want to show menu 3 at the top…

How can this be done?
Custom menu on posts in a particular category?

P.S.: I am well versed with HTML/CSS, but not php, but can definitely try my bit at php if someone helps…