The Compendium of Caraka 6.19.4_3

6.19.4_3

ataśca pratyavarakālaṃ pṛṣadhreṇa dīrghasatreṇa yajatā paśūnāmalābhādgavāmālambhaḥ pravartitaḥ/

And in a time later than that, by Pṛṣadhra performing a long sacrificial session, the slaughter of cattle was introduced because of the unavailability of animals.