em-mail.betrend.com has no NS records.
NS records for this zone are defined at betrend.com.
NS records for this zone are defined at betrend.com.
Question and response
Question
dig em-mail.betrend.com. NS
Answer
The response has no answer records.
Authority
betrend.com. 2560 SOA ns.jp.betrend.com. bt_mis.betrend.com. 1773383686 16384 2048 1048576 2560
Additional
The response has no additional records.