DNS replication in a single forest with multiple child DC's

HIi,

Currently, we have 10 DC’s in root and some 30 DC’s as child. Now if we promote any additional DC for child we will add secondary DNS zone of root DNS in child DC’s, which we don’t like it.
So now we if we promote any additional DC for child it should come up with ROOT DNS, we should not add ROOT DNS as secondary zone in child DC. How can we achieve this?

Thanks in advance

Shiva