Ashtangasamgraha 7.107

7.107

gurūṇyaṇḍāni bālānāṃ kaṣāyamadhuraṃ palam |

vṛddhānāṃ snāyubhūyiṣṭhamabalyaṃ gurudoṣalam ||

tatpayomūtraviḍvṛttipariṣekapragharṣaṇaḥ |

tābhiḥ parivṛtaḥ svapyāttacchakṛdreṇusaṅkare ||

Eggs are heavy; the meat of young animals is astringent and sweet;
that of old animals has an abundance of sinews, is not strengthening, and is heavy and vitiating to doṣas.
Wetting and rubbing oneself with their milk, urine, and dung,
surrounded by them, one should sleep in the mixture of their dung and dust.