dns-recursion.nse Server Status Opcode 2 where comes from?

Good day everyone,
I am trying to understand in running this script why does nmap (v7.01) send
on every target as 1st packet  Server Status request (OPCODE 2
https://www.ietf.org/rfc/rfc1035.txt)  ? Running on the same system "dig"
does not produce it.
I am asking because some vendors started blocking scans on this packet
(scanning the same IPs using dig does not get me blocked) and basically
I'd love to disable this feature.
Thanks
cmd: nmap -sU -P0 -p 53 --script=dns-recursion 8.8.8.8
[image: Inline image 1]
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