Jaiminīya (Talavakāra) Brāhmaṇa 37.212

Then the Mārgīyava with a word-refrain, connected with the Rathantara.
Therefore it is performed on a Rathantara day.
Mṛgayu, a god, indeed desired: "May I attain lordship and overlordship over both kinds of cattle—those that are domestic and those that are wild."
He saw this sāman.
With it he praised.
Thereupon he indeed attained lordship and overlordship over both kinds of cattle—those that are domestic and those that are wild.
From then on, a wild beast (mṛga) would fetch a wild beast for him.
That is a cattle-procuring sāman.
He attains lordship and overlordship over both kinds of cattle—those that are domestic and those that are wild, who knows thus.
That indeed is that god Mṛgayu;
he does not plot against the cattle of him who knows thus.
And because the god Mṛgayu saw it, therefore it is called Mārgīyava.

"Towards [the strainer], the active somas—"

—with the word "towards" (abhi) it contains the form of the Rathantara.

This day is connected with the Rathantara.

"—clarify the intoxicating drink,"

"Upon the ridge of the ocean, the wise, exhilarating, intoxicating drops—"

—thus [the verses] contain the word "ocean" (samudra), the form of the Chandomas.

The ocean indeed is the Chandomas.

"Crossing the ocean with a wave, purifying, king, god, high truth,"

"Flow according to the law of Mitra and Varuṇa, advancing high truth,"

"Held by men, eager for the bays, far-seeing, the kingly divine one of the ocean."

Thus it is a four-verse hymn; four-footed indeed are cattle.

Cattle are the Chandomas, for the attainment of cattle.

On these [verses], the Vāmadevya with two hiṃ-sounds.