Enables alpha-N-acetylgalactosaminide alpha-2,6-sialyltransferase activity. Involved in glycosphingolipid biosynthetic process and oligosaccharide biosynthetic process. Predicted to be located in Golgi apparatus and membrane. Predicted to be integral component of membrane. Is expressed in several structures, including alimentary system; genitourinary system; heart; nervous system; and respiratory system. Orthologous to human ST6GALNAC5 (ST6 N-acetylgalactosaminide alpha-2,6-sialyltransferase 5). [provided by Alliance of Genome Resources, Apr 2022]