Manava Dharmashastra 5.133

5.133

etāni dvādaśamalāni darśitāni | nṛgrahaṇaṃ pañcanakhānāṃ pradarśanārtham | śvaśṛgālādīnāṃ tvaspṛśyatvādeva siddham | viṇmūtre tu sarvasyājāvikagavāśvebhyo'nyatra |

Medhātithi’s commentary (manubhāṣya):
The twelve ‘excretions’ or ‘impurities’ are here indicated.

‘Human beings’ includes all five-nailed animals. As regards dogs and jackals, their excretions are impure by reason of their own untouchability.

‘Urine and ordure’—of all animals, except those of the goat, the sheep, the cow and the horse.—(133).