Śatapatha Brāhmaṇa ("of a hundred paths") 14.1.2.13

14.1.2.13

athājākṣīram yajñasya śīrṣacinnasya śugudakrāmattato'jā samabhavattayaivainametacucā samardhayati kṛtsnaṃ karoti makhāya tvā makhasya tvā śīrṣṇa ityasāveva bandhuḥ

Then goat's milk;---for when the sacrifice had its head cut off, its heat went out of it, wherefrom the goat was produced: it is with that heat that he thereby supplies and completes it;--with, 'For Makha thee! for Makha's head thee!' the import of this is the same as before.