Apex domains cannot have CNAME records.
Question and response
Question
dig agrinet.ch. NS
Answer
agrinet.ch. 1 NS ns01.as1836.ch.
agrinet.ch. 1 NS ns01.as1836.net.
agrinet.ch. 1 NS ns01.agrinet.ch.
Authority
The response has no authority records.
Additional
ns01.agrinet.ch. 1 A 194.191.21.252
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0