mx.cgocable.ca has no NS records.
NS records for this zone are defined at cgocable.ca.
NS records for this zone are defined at cgocable.ca.
Question and response
Question
dig mx.cgocable.ca. NS
Answer
The response has no answer records.
Authority
cgocable.ca. 3600 SOA ns3.cgocable.ca. postmaster.cgocable.ca. 2017084831 10800 600 3600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0