Mahabharata 12.159.25

उदपानोदके ग्रामे ब्राह्मणो वृषलीपतिःउषित्वा द्वादश समाः शूद्रकर्मेह गच्छति

udapānodake grāme brāhmaṇo vṛṣalīpatiḥuṣitvā dvādaśa samāḥ śūdrakarmeha gacchati

Our plain-language meaning of this verse is waiting for scholar review.