Changes in vSphere 6.0 Logs details as compared to vSphere 5.x

In vSphere 6.0 any action perform against the ESXi hosts from vCenter Server listed as [user=vpxuser:DOMAIN\user]as given in the screenshot:-

In vSphere 5.5 any action perform against the ESXi hosts from vCenter Server listed as [user=vpxuser] as given in the screenshot:-