Shatapatha Brahmana 9.5.1.40

9.5.1.40

tadāhuḥ | naitāni havīṃṣi nirvapennedatirecayānīti tāni vai nirvapedeva kāmebhyo vā etāni havīṃṣi nirupyante na vai kāmānāmatiriktamasti yadvai kiṃ ca paśupuroḍāśamanu havirnirupyate paśāveva sa madhyato medho dhīyata ubhayāni nirvapatyadhvarasya cāgneścādhvarasya pūrvamathāgnestasyokto bandhuruccaiḥ paśupuroḍāśo bhavatyupāṃśvetānīṣṭirhyanubrūhi preṣyeti paśupuroḍāśasyāhānubrūhi yajetyeteṣāmiṣṭirhi samānaḥ sviṣṭakṛtsamānīḍā

As to this they say, 'He should not offer these oblations, lest he should do what is excessive.' Let him nevertheless offer them; for these oblations are offered for (the fulfilment) of (special) wishes, and in wishes there is nothing excessive. And whatever oblation is offered after the cake of the animal-offering that is placed inside the victim itself as its sacrificial sap. He offers both kinds (of oblations), those of the Soma-sacrifice and those of the Agni(-kayana), to wit, first those of the Soma-sacrifice, and then those of the fire-altar: the significance of this has been explained. The cake-offering of the animal sacrifice is (performed) in a loud voice, and these (five oblations) in a low voice, for they are an ishti. With the Pasupurodâsa he (the Adhvaryu) says, 'Recite!--Urge!' and with these (oblations), 'Recite!--Worship!' for they are an ishti. There is the same Svishtakrit, and the same Idâ.