Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 2 · Signs, Planets, Birth
जातकम् १
क्लीबे तदूशनाद्वापि चंद्रार्कांशसमं जनुः ।स्वांशे पापाः परांशस्थाः सौम्यालग्नं वियोनिजम् ॥ ३२ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 55, verse 32.
A neuter planet may be there, or see it. Then the creature born is like the Moon's navamsha (one-ninth part of a sign). Bad planets stand in their own navamsha. Good planets stand in others' navamsha. The lagna (rising sign) is in a non-human sign. (Our text is unclear here: two words in the first line are damaged.)
Simple meaning: Bad planets in their own navamsha, good ones in others', and an animal-sign lagna point to a non-human birth.
निर्बलं च तदादेश्यं वियोनेर्जन्म पंडितैः ।
A weak lagna can mean a non-human birth. The verse then lists the creature's body parts.
पार्श्वे कुक्षी त्वपानांघ्री मेढ्रमुष्कौ तथा स्फिजौ ।
For a four-footed animal, the signs from Aries on stand for its body parts in this order.
लग्नांशाद्ग्रहयुग्दृष्ट्वा वर्णान्बलयुताद्वदेत् ।
An animal's colours come from the lagna's navamsha or the strongest planet tied to it. The 7th gives stripes.