mxout04.pr.gov.br has no CNAME records.
Question and response
Question
dig mxout04.pr.gov.br. NS
Answer
The response has no answer records.
Authority
pr.gov.br. 10547 SOA pr.gov.br. root.pr.gov.br. 2026022603 1800 300 3600000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0