On board Loadies used on most aircraft.
dc-8's
b707's
tristars
Dc-10
Mostly depends on the airline - the more adhoc ops - the more onboard loadies used . For sked cargo airlines, most have station loadies at major hubs.
All of the Russian aircraft have loadmasters on board. An-12 has 1 loadmaster and 4-5 assistants that dbl as ground engineers.
Our B747's have station loadies, but when we do complicated charters we ensure that we have a loadmaster on board travelling with the cargo.