The Upanishads, Part 1 (SBE01), by Max Müller, , at sacred-texts.com
1. Let a man meditate on the fivefold Sâman in animals. The hiṅkâra is goats, the prastâva sheep, the udgîtha cows, the pratihâra horses, the nidhana man.
2. Animals belong to him, nay, he is rich in animals who knowing this meditates on the fivefold Sâman as animals.