spf01.tnc.ne.jp has no CNAME records.
Question and response
Question
dig spf01.tnc.ne.jp. NS
Answer
The response has no answer records.
Authority
tnc.ne.jp. 69 SOA dns0.tokai.or.jp. postmaster.tokai.or.jp. 202601002 3600 300 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0