[Show abstract][Hide abstract] ABSTRACT: The effectiveness of the Hydrodyne process and low voltage carcass electrical stimulation (ES), either alone or in combination, for tenderizing muscle from callipyge and normal lambs was evaluated. One hundred grams of explosive was used for the Hydrodyne treatment. Reductions in shear force with magnitudes of 33 to 67% were observed for the Hydrodyne treatment for the longissimus (LM) muscle from callipyge and normal lambs, respectively. Carcass ES had no effect (P>0.05) on either callipyge or normal lamb shear values. However, ES improved the response (48%) of the Hydrodyne treatment in the LM of callipyge lamb. Shear force for semitendinosus muscles averaged 3.53 kg and showed no response to either tenderizing treatment. Results suggest successful tenderization of lamb LM with the Hydrodyne technology.