Jaiminīya (Talavakāra) Brāhmaṇa 1.67

1.67

None exceeds the twelfth,
for they are enclosed by it.
While they were being enclosed, a mule bounded out.
Running after it, he took its seed.
He rubbed it onto a donkey, onto a mare, onto cattle, onto plants.
Therefore the donkey has double seed; therefore the mare has double seed;
therefore cattle give birth to two each;
therefore plants crackle when not anointed [with oil].
Therefore a mule is not to be given on the sacrificial grass,
for it bounded over, it stepped aside;
for its seed has been taken away, for it is barren.
It is to be given at the chant of the Ṣoḍaśin.
The Ṣoḍaśin is an addition among the chants; the mule is an addition among animals.
They place the redundant into the redundant, for the smoothness of the sacrifice.
He who, knowing thus, chants as Udgātṛ with the Agniṣṭoma generates procreated offspring and encloses the procreated offspring.
This Agniṣṭoma is indeed the sacrifice of the eldest, the sacrifice of Prajāpati.
He attains seniority and supremacy who knows thus.