MinaMikhailcom

for i in domain1.com domain2.com domain3.com domain4.com domainXetc.com; do echo $i : $(dig NS $i +short); done 

OR:
for i in `cat domainslist.txt`; do dig ns $i;  done

<Domain list created in "domainslist.txt" file)
<Change Record type from NS to any other>