Agni Purana (Jyotisha Selections) · by Vyasa
Chapter 5 · Omens
शकुनानि
शिवाय स्वामिनो रात्रौ बलीवर्दो नदन्भवेत् ।उत्सृष्टवृषभो राज्ञो विजयं संप्रयच्छति ॥ २२ ॥
In the full Agni Purana this is chapter 232, verse 22.
A bull bellowing at night is for the owner's good. A bull that has been set free gives the king victory.
Simple meaning: A bull bellowing at night is good for its owner. A freed bull gives the king victory.
अभक्ष्यं भक्षयन्त्यश्च गावो दत्तास्तथा स्वकाः ।
Cows that eat wrong things or drop love for their calves are said to bring a loss of the unborn.
भूमिं पादैर्विनिघ्नन्त्यो दीना भीता भयावहाः ।
Cows pawing the ground and frightened bring fear. Wet cows with soil on their horns are good.
महिष्यादिषु चाप्येतत्सर्वं वाच्यं विजानता ।
All this holds for buffaloes too. Someone else riding one's saddled horse is not good.