mx.alog.com.br has no NS records.
NS records for this zone are defined at alog.com.br.
NS records for this zone are defined at alog.com.br.
Question and response
Question
dig mx.alog.com.br. NS
Answer
The response has no answer records.
Authority
alog.com.br. 3600 SOA dns1.p07.nsone.net. hostmaster.nsone.net. 1649794102 1200 600 43200 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0