I´m work witn South American Camelids (cousins of camel), but production systems are very similar, I´m have some doudts about your questions, can you clarify somethngs??

I suppose by these three camel breeding modes: breeding hampered without access to pasture, livestock with forage crop (semi-extensive) and free livestock grazing (extensive) !

I´m agree with these models, but, itsn´clear for me were is the problem, what is the questions???, different production systems adjust on diferent environmental and econmical condition,some problem with Camels production in relation on both items??

Dromedary camels in Arabia are usually reared in two main systems: (1) camels are  left unconfined in open desert areas (free system) and (2)  camels kept in pens (intensive system). Both systems might be used in one herd.

Our group studied the effect of these housing systems on the incidence of dystocia. The risk of occurrence of dystocia was higher

in camels housed in intensive systems (12.6%, 66/526) than

in those in free systems (7.1%, 97/1267) (Odds ratio = 1.9,

P = 0.0003) (see full paper, attached).

Ahmed ali

May be you mean house-hold landless system the free ranging system in which camels were mainly kept for household and solely depend on browsing. Crop-livestock system may refer to system where camels were kept in a semi-intensive system and where they graze the crop cultivation  resides. and the ranching system could refer to the confined intensive system.

Let me say that ranching involve s extensive free range systems with known land size with inbiuld infrastructure e.g water, vet care , milking.

I´m agree with colleague Musimba, ranching refers to a extensive free grazing system with a minimal facilities provided.

My understanding of household landless system is solely indoor feeding whereby the camels are fed on rations for milk production, where's crop_livestock may equally imply a crop system raising grain/cereals for livestock feeding.