Fig. 1

Type I-predominant skeletal muscles from OCPMD-affected sheep show extensive muscle degeneration and likely nemaline bodies. a Whole soleus muscles from a 10-year old unaffected carrier ewe and an 8-year old affected ewe. b Hematoxylin and eosin (H&E) stained longitudinal section of type I myofibre-predominant skeletal muscle (soleus) from an OCPMD-affected sheep; shows increased presence of collagenous connective tissue and fat (white/unstained; e.g. area indicated by arrow). c, d H&E (left) and Gomori trichrome (right) staining of soleus muscles from 5-year old (c) and 8-year old (d) affected sheep. Shows extensive variation in myofibre size, central nuclei (#), split myofibres (+), and basophilic infiltration (*). Gomori stains show the presence of sarcomeric protein aggregates—likely nemaline bodies within myofibres (dark areas, see arrowheads). All scale bars = 50 µm