mx03.start.ca has no CNAME records.
Question and response
Question
dig mx03.start.ca. NS
Answer
The response has no answer records.
Authority
start.ca. 192 SOA dns61.telus.com. dnsadmin2.telus.com. 2025061896 3600 600 3600000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0