During the second Israeli-Lebanon war in 200062006, one Israeli brigade used llamas. http://israelity.com/2009/01/28/idf-recruits-antelope-to-guard-northern-border/Israeli brigade used llamas. However, the IDF are considering releasing their stocks of Oryxes,Llamas and Barbary sheep who have been faithfully serving Israel for some years. http://www.jewpi.com/idf-mulls-releasing-oryxes-llamas-and-barbary-sheep/
Llamas have advantages over mules for cross country work but have difficulty in terraced terrain. They don't like big steps. The antelopes will stay as their skills in brush clearance make them appreciated. Apparently , veterinary care is the main driving factor here. Antelopes are low maintenance whilst llamas are not, with dental work being quite costly.