Shatapatha Brahmana 13.1.3.8

13.1.3.8

tadāhuḥ yadyajñamukhe-yajñamukhe juhuyātpaśubhirvyṛdhyeta pāpoyāntsyātsakṛdeva hotavyā na paśubhirvyṛdhyate na pāpīyānbhavatyaṣṭācatvāriṃśataṃ juhotyaṣṭācatvāriṃśadakṣarā jagatī jāgatāḥ paśavo jagatyaivāsmai paśūnavarunddha ekamatiriktaṃ juhoti tasmādekaḥ prajāsvardhukaḥ

Concerning this they say, 'Were he to offer at each opening of sacrifice, he would be deprived of his cattle, and would become poorer.' They should be performed once only: thus he is not deprived of his cattle, and does not become poorer. Forty-eight (oblations) he offers;--the Gagatî consists of forty-eight syllables, and cattle are of Gâgata (movable) nature: by means of the Gagatî he (the Adhvaryu) thus wins cattle for him (the Sacrificer). One additional (oblation) he offers, whence one man is apt to thrive amongst (many) creatures (or subjects).