Lyrics below are from the sheet music at the Library of Congress. You can hear a 1920 recording by Harry C. Browne and The Harmonizers at The Internet Archive:

[This is presented for historical interest only; I don't recommend singing it, due to its blatant racism. The tune is nice, though.]

DARS A LOCK ON DE CHICKEN COOP DOOR
Words and music by Sam Lucas, ©1885.

1. Dis kintry's gwine to de dogs at last when de farmer sets a watch
And a big bull dog and a big steel trap in de watermillion patch;
An' wus dan all dat's happened yet dat makes us all feel sore,
Whenebber you trabbel around, you'll find dar's a lock on de chicken coop door.

CHORUS: Oh! Aunt Susan! Did you eber hear ob dat before?
Wharebber you trabbel around, you'll find dar's a lock on de chicken coop door.

2. De pullets dey flop dar wings and crow when a darkey passes by.
Dey seem to say dat dey can't be cotched and it ain't no use to try.
Oh! Gabriel blow de mighty horn! We can't stay here no more,
For if we do, we will starve to death; dar's a lock on de chicken coop door.

3. And when we've a wedding party now, oh! what am we a-gwine to do?
Oh! whar am de pullets a-comin' from for to put dat party froo?
Oh! hang up de banjo on de wall; we'll rattle de bones no more.
Dis kintry's gwine to de dogs at last; dar's a lock on de chicken coop door.

[The following verse is sung in the linked recording, but does not appear in the sheet music:]

4. Oh, what is a darky gwine to do when the parson's asked to eat
And there ain't no fowl to feed him with as he sits there in his seat?
The good Lord knows it isn't right to tease a darky so.
It's just enough to break his heart; there's a lock on the chicken coop door.