If you are aiming for traffics from Google, the last thing you want to end up is having duplicates of a same content being indexed by Google. They will eventually being treated as supplemental. Feeds is one of the content you don’t want to get indexed as they are duplicates of your original contents. Here’s few ways to remove feeds from getting indexed drawn after a little discussion with Ashish.

Add nofollow to Feed Button

Check your feed button, make sure it comes with a rel="nofollow" within the hyerlink codes.

Add nofollow to Comment Feeds and Trackbacks

If you provide feeds and trackback for single post, you should add rel="nofollow" to them too. Adding these codes varies from themes to themes, but big chance you might find them inside comments.php.

Activate NoIndex in Feedburner

If you are using Feedburner, head over to Publicize -> NoIndex and check on Indicate that your feed should not be indexed by search engines.

Add Disallow /feed in robots.txt

Add these following into your robots.txt to suggest feed related contents should not be crawled.

Disallow: /feed/
Disallow: /*/feed/
Disallow: /*/feed/rss/

This should stop bots from indexing all contents related to feeds.