Śatapatha Brāhmaṇa ("of a hundred paths") 5.3.3.7

5.3.3.7

atha rudrāya paśupataye | raudraṃ gāvedhukaṃ caruṃ nirvapati tadenaṃ rudra eva paśupatiḥ paśubhyaḥ suvatyatha yadgāvedhuko bhavati vāstavyo vā eṣa devo vāstavyā gavedhukāstasmādgāvedhuko bhavati

For Rudra Pasupati (lord of beasts) he then prepares a Raudra pap of gavedhukâ seeds (coix barbata): thereby Rudra, the lord of beasts, quickens him for cattle. And as to its being prepared of gavedhukâ seed;--that God is (the recipient of) refuse (remains of offering), and gavedhukâ seeds are refuse: therefore it is (prepared) of gavedhukâ seed.