Even though they might not have enough food in their own stomachs, Tibetan peasants would feed their draught cattle with the best food, as they depended on them for plowing. Such good treatment lasted until the animals died, after which, some peasants would bury them in their own fields, then remove the bones at a much later date and carve a Six Syllable Prayer on the skulls for a lasting memory.
Herein lies the tradition of the Tibetan race: Love of all living things, which would never end up on the dinner table no matter how hungry people might be.
In return for the contribution made by milk cows, the host families will set some of them free when they become too old to produce milk.
Of course, this is more than a tradition. It is actually part of Tibetan Buddhism.
In ancient times, the Tibetans worshipped the Bon religion, featuring worship of spirits related to heaven, earth, mountains, forests and great nature. Belief was so strong that worshippers would kill animals as sacrificial objects to these spirits. History books record the existence of “blood rivers and meat mountains.”
Such a situation lasted until Buddhism replaced the Bon religion with doctrines that forbade killing. This gave birth to the new tradition of setting free animals when they were old or when they were caught by chance.