mx.xenoraventa.com has no NS records.
NS records for this zone are defined at xenoraventa.com.
NS records for this zone are defined at xenoraventa.com.
Question and response
Question
dig mx.xenoraventa.com. NS
Answer
The response has no answer records.
Authority
xenoraventa.com. 3600 SOA dns.xenoraventa.com. hostmaster.xenoraventa.com. 1206460577 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0