tatra there, yathāśāstram as per tradition, pracōditā: prompted, paśava: animals, uragā: serpants, pakṣiṇaścaiva birds also, tattat that respective, daivatam deity, uddiśya intended for, niyuktā: were fastened.
Animals, serpents and birds were kept ready after the sastras intended (for sacrifice) for those respective deities.