Organ farms were an Tlulaxa innovation to produce replacement organs for the casualties before and during the Butlerian Jihad. Cloned organs and tissues could be grown and cultivated in artificial farms, and then sold commercially all around the League of Nobles.
Xavier Harkonnen after the Battle of Zimia received a set of replacement lungs from the Tlulaxa farms. Although he lived, Xavier's sense of smell and taste suffered from the damage inflicted.
Eventually, a horrible truth was exposed pertaining to the organ farms. During the Jihad, demand of the organs was augmented and the Tlulaxa (who also worked as slavers) had to rely on slaves and captives. Xavier found out that Grand Patriarch Iblis Ginjo had supported Tlulaxa raids into the Unallied Planets for fresh supplies for the organ farms. During the peak of the war, the Unallied Planets could not cover the demand, so slavers had to attack League Worlds and set them up so as to appear machine assaults. Worlds that fell victims of the slavers were Chusuk and Rhisso.
Serena Butler insisted to approach the secretive Tlulaxa, despite their reluctance, hoping to make them join the League. Along with Ginjo and Rajid Suk, they paid a visit to the world and explored the farms outside Bandalong, where the captive "donors" were held. However the truth was well concealed from them.
Some years later, Xavier with Iblis also visited the planet until he was cntacted by a captive, Hondu Crehg who guided him in the pens where the captives lived, and revealed the truth and Ginjo's role in it. Xavier to end this, set their ship shuttle to auto-pilot and flew into the Thalim sun killing himself and Iblis Ginjo. Although the exact details were no given to the public, the truth about the slaves was revealed, and the Tlulaxa were condemned from the human society in the following years.