Matsya Purana — Manvantaras
पशूनां पक्षिणां चैव स्थावराणां च सर्वशः गावो ऽजाश्वाश्च विज्ञेया हस्तिनः पक्षिणो मृगाः //
paśūnāṃ pakṣiṇāṃ caiva sthāvarāṇāṃ ca sarvaśaḥ gāvo 'jāśvāśca vijñeyā hastinaḥ pakṣiṇo mṛgāḥ //
Among animals, birds, and even all stationary beings, distinct classes are to be recognized: cows, goats, and horses; likewise elephants, birds, and wild beasts.
This verse is not about Pralaya; it functions as a practical dharma-style classification of beings, naming key domestic and wild categories relevant to human society.
By listing cows, goats, horses, and elephants alongside birds and wild animals, it reflects the social-ritual economy a king and householder must manage—protection of cattle, regulation of animal use, and orderly recognition of categories for law, gifting, and livelihood.
No direct Vāstu rule is stated here; the ritual significance is indirect—these categories (especially cows and other livestock) underpin offerings, gifts (dāna), and household maintenance in Purāṇic practice.