Apex domains cannot have CNAME records.
Question and response
Question
dig eaav.gov.co. NS
Answer
eaav.gov.co. 5 NS ns6141.hostgator.com.
eaav.gov.co. 5 NS ns6142.hostgator.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0