Export/import windows server DNS zones

You can use Export-DnsServerZone and Import-DnsServerZone. 

1. Export: Export-DnsServerZone -Name "test.com" -Filename "test.com.dns"
2. Import: Import-DnsServerZone -Name "test.com" -Filename "test.com.dns"

The file "test.com.dns" will be created in "C:\windows\system32\dns" folder

Only export dns records:

Get-DnsServerResourceRecord -ZoneName "test.com" | Export-Csv -Path "C:\temp\dns.csv"