Valmiki Ramayana Bala Kanda Sarga 14 Shloka 28
Original Shlokaनियुक्तास्तत्र पशवस्तत्तदुद्दिश्य दैवतम्। उरगा: पक्षिणश्चैव यथाशास्त्रं प्रचोदिता:।।1.14.28।।
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तत्र there, यथाशास्त्रम् as per tradition, प्रचोदिता: prompted, पशव: animals, उरगा: serpants, पक्षिणश्चैव birds also, तत्तत् that respective, दैवतम् deity, उद्दिश्य intended for, नियुक्ता: were fastened.
Animals, serpents and birds were kept ready after the sastras intended (for sacrifice) for those respective deities.