Including /feed/ at the end of the urls

Hello guys,

In the Google Webmaster Tool there has been an increasing increase in Crawl Errors. And when I checked the errors, I found several URLs of posts where in the end they contained / feed / like:

http://proddigital.com.br/produtos-digitais/investimentos/como-operar-os-indices-mundiais-metodo-investidor-de-sucesso/feed/

http://proddigital.com.br/produtos-digitais/relacionamentos/livre-se-de-dependencia-emocional-de-seu-parceiro-a/feed/

http://proddigital.com.br/produtos-digitais/casa-e-construcao/feed/

http://proddigital.com.br/produtos-digitais/arte-e-design/feed/

These URLs are returning error 404. But the posts do exist.

These posts are in a Custom Category (/ digital-products /). Will Custom Categories have no feed page, or are they not finding it?

Is there anything I can do with Redirection to solve this problem?

Thanks for the help.
Rodrigo Carlos