Śatapatha Brāhmaṇa ("of a hundred paths") 1.2.3.6

1.2.3.6

puruṣaṃ ha vai devāḥ | agre paśumālebhire tasyālabdhasya medho 'pacakrāma so 'śva praviveśa te 'śvamālabhanta tasyālabdhasya medho 'pacakrāma sa gām praviveśa te gāmā ... so 'vim praviveśa te 'vimā ... ma so 'jam praviveśa te 'jamālabhanta tasyālabdhasya medho 'pacakrāma

At first, namely, the gods offered up a man as the victim. When he was offered up, the sacrificial essence went out of him. It entered into the horse. They offered up the horse. When it was offered up, the sacrificial essence went out of it. It entered into the ox. They offered up the ox. When it was offered up, the sacrificial essence went out of it. It entered into the sheep. They offered up the sheep. When it was offered up, the sacrificial essence went out of it. It entered into the goat. They offered up the goat. When it was offered up, the sacrificial essence went out of it.