Shatapatha Brahmana 7.5.2.33

7.5.2.33

athāśvasya | imam mā hiṃsīrekaśapham paśumityekaśapho vā eṣa paśuryadaśvastam mā hiṃsīrityetatkanikradaṃ vājinaṃ vājineṣviti kanikrado vā eṣa vājyu vājineṣu gauramāraṇyamanu te diśāmīti tadasmai gauramāraṇyamanudiśati tena cinvānastanvo niṣīdeti tena cinvāna ātmānaṃ saṃskuruṣvetyetadgauraṃ te śugṛcatu yaṃ dviṣamastaṃ te śugṛcatviti tadgaure ca śucaṃ dadhāti yaṃ ca dveṣṭi tasmiṃśca

Then that of the horse, with (Vâg. S. XIII, 48), 'Harm not this one-hoofed animal!' the one-hoofed animal doubtless is the same as the horse: thus, do not harm that one!--'the racer neighing among the racers;' for neighing indeed he is, and a racer among racers;--'The wild fallow (beast) do I assign unto thee,' he thereby assigns to him the wild fallow (beast);--'building up therewith thy forms, get thee settled!' that is, 'building up therewith, perfect thyself!'--'Let thy burning heat reach the fallow beast! let thy burning heat reach him whom we hate!' he thereby lays burning heat into the fallow beast, and into him whom he hates.