AbstractCardiomyoplasty has the potential to become an alternative therapy for congestive heart failure patients and is presently in Phase III clinical trials. In experimental studies, it is necessary to use an animal with muscle characteristics that resemble those of humans. Therefore, the purpose of this study was to compare morphological and biochemical characteristics of the latissimus dorsi muscle (LDM) of three common large mammals with those of human. Of the three mammals studied, the goat had the most overall similarities to the human when comparing mitochondrial capacity, percent fiber types, fiber areas, myofibrillar (MF)‐AT‐Pase activity, and 72‐kDa heat shock protein (HSP) content. The pig was dissimilar to the human in its fiber‐type arrangement, glycolytic capacity, percent fiber type, MF‐ATPase activity, and HSP‐72 content. The dog differed from the human in that it had high‐mitochondrial enzyme activity, a fiber‐type profile consisting of all high‐aerobic fibers, and fiber cross‐sectional areas that were nearly half those of humans. These findings show that the LDM of the goat most resemble