Parenchymal tissue that consists of the alveoli, grape-like clusters where milk is stored, and branching ducts, which are tubular canals carrying gladular secretions. [ https://orcid.org/0000-0003-3308-6245 https://github.com/obophenotype/uberon/issues/1349 http://www.newworldencyclopedia.org/entry/Mammary_gland ]