Domestication
From Transformers Wiki
Domestication is a gruesome form of torture, a medical process designed to denigrate and humiliate Transformers who possess beast modes. By lobotomizing the Transformer in question, mutilating their voice box, and subsequently denting their transformation cog, the victim becomes little more than a feral animal, unable to comprehend their situation or return to robot mode.
Fiction
2005 IDW continuity
Dominus Ambus served as a mole within the Decepticon Justice Division until his cover was eventually blown. As retribution, Kaon had Dominus domesticated, leaving him permanently trapped as a turbofox that his tormentor adopted, nicknaming him "The Pet". At Close of Day
After the end of the war, the ex-Decepticon Demus began kidnapping and domesticating beast mode Transformers, marketing them as fun "Roboid" toys. These half-dead "toys" were marketed to violent, robophobic species across the galaxy, and buyers tended to use them as torture dolls; the Roboids in question were just sentient enough to feel the pain. Following Demus's death, Fortress Maximus took custody of the Roboids, and Spinister left Maximus a note explaining how to reverse the domestication process. Animals
Back on Luna 1, Cerebros was tasked with reversing the procedure. Although Spinister's techniques were successful, they were also time-consuming, and months later only a fraction of the Roboids had been rehabilitated. Cerebros developed a brain implant that would speed up the process greatly, but Fortress Maximus and Red Alert refused to allow its use. Ten to Midnight After defeating Sentinel Prime, they changed their minds and the remaining Roboids were rapidly repaired and returned to Cybertron. Last Light