Apex domains cannot have CNAME records.
Question and response
Question
dig smtp08.lidc.telus.com. NS
Answer
smtp08.lidc.telus.com. 4 NS dns02.lidc.telus.com.
smtp08.lidc.telus.com. 4 NS dns01.lidc.telus.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0