The Teatro San Carlo has announced two cast changes for its March 12 performance of Verdi’s “Macbeth.” The company said that due to illness Sondra Radvanovsky will not sing the role of Lady Macbeth and will be replaced by Daniela Schillaci. Meanwhile, George Gagnidze will sing the title role taking over for Luca Salsi. Schillaci performed the role on opening {…}