mx.hockeycats.com has no NS records.
NS records for this zone are defined at hockeycats.com.
NS records for this zone are defined at hockeycats.com.
Question and response
Question
dig mx.hockeycats.com. NS
Answer
The response has no answer records.
Authority
hockeycats.com. 3600 SOA dns.hockeycats.com. hostmaster.hockeycats.com. 1320041871 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0