As of 6-6-14, Citrix Netscaler 10.1 is not supported on Hyper-V 2012 R2. Hyper-V 2012 R2 will be supported in the next revision of Netscaler (version 10.5) hopefully due out end of Q2. NetScaler 10.5 was available for demo at Citrix Synergy so I anticipate it will be released shortly.
Citrix will support getting Netscaler 10.1 imported on Hyper-V 2012 (R1), however work arounds are needed to account for the changes made by Microsoft between 2008 R2 and 2012.