There are similarities and differences. One still doesn't want airlocks in the tractor hydraulic cylinders.

The Tractor couplers (Parker/Granger above) have a little nipple in the end to keep oil from leaking out, and I assume something similar on the female end. I'm not sure how much, if any air is introduced with coupling/disconnecting, but it would be minimal.

As I noted in my second post, apparently Formula uses a similar method for their speedlock system.

There are a number of small connectors here too.
Hydraulic - range of non spill quick coupling for medium to high pressures circuits*-*Stäubli