spf.ocn.ad.jp has no CNAME records.
Question and response
Question
dig spf.ocn.ad.jp. NS
Answer
The response has no answer records.
Authority
ocn.ad.jp. 600 SOA ns1.ocn.ad.jp. postmaster.ocn.ad.jp. 20396 10800 3600 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0