mx.cogeco.ca has no NS records.
NS records for this zone are defined at cogeco.ca.
NS records for this zone are defined at cogeco.ca.
Question and response
Question
dig mx.cogeco.ca. NS
Answer
The response has no answer records.
Authority
cogeco.ca. 43200 SOA ns1.cgocable.net. dnsadmin.cgocable.net. 2007688092 1800 7200 86400 43200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0