The post by Rabbitrunning, with the extended refrain, is the same as the version in N. G. J. Ballanta-(Taylor), 1924, "Saint Helena Island Spirituals."
The spiritual was included for the first time in the 1909 edition of "Religious Folk-Songs of the Negro," when Robert R. Moton was Commandant of the Hampton Institute. The 1927 edition, edited by R. Nathaniel Dett, includes the extended chorus, which includes the 'sheep' lines, in Appendix IV; the lines are omitted altogether in a version on p. 79, "Transcribed by R. Nathaniel Dett."

The 1909 version is transcribed in "Saint Helena Island Spirituals."
For the sake of accuracy and completeness, here are the lyrics with the extended chorus: