mx1.lightpath.net has no NS records.
NS records for this zone are defined at lightpath.net.
NS records for this zone are defined at lightpath.net.
Question and response
Question
dig mx1.lightpath.net. NS
Answer
The response has no answer records.
Authority
lightpath.net. 86400 SOA authns1.cv.net. abuse.cv.net. 2013413049 7200 600 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0