Donkey milk in history: Varro

The Roman scholar Varro ranked the types of milk in 37 BC: sheep's milk was the most nutritious, mare's milk the strongest laxative – donkey's milk followed in second place.

The source in brief

• Author: Marcus Terentius Varro
• Work: Res rusticae (Conversations on Agriculture)
• Passage: Book 2, Chapter 11, Section 1; additionally Book 2, Chapter 8, Section 2
• Time and place: 37 BC · Roman Republic (Italy)
• Type of source: Roman agricultural text

The original text

Lacte est omnium rerum, quas cibi causa capimus, liquentium maxime alibile, et id ovillum, dein caprinum. Quod autem maxime perpurget, est equinum, tum asininum, dein bubulum, tum caprinum.

Milk is the most nutritious of all the liquids we consume for food, namely sheep's milk, followed by goat's milk. But mare's milk is the strongest laxative, then donkey's milk, then cow's milk, then goat's milk.

Latin, Varro, rust. 2,11,1

Pullum asininum a partu recentem subiciunt equae, cuius lacte ampliore fiunt, quod id lacte quam asininum ad alimonia dicunt esse melius.

A newborn donkey foal is placed under a mare, through whose milk it grows stronger; for it is said that this milk is better for rearing than donkey's milk.

Latin, Varro, rust. 2,8,2

German translation: own, sense-for-sense translation by the DON DONKEY'S editorial team.

Background

Marcus Terentius Varro (116–27 BC) was a versatile scholar of the late Roman Republic. He wrote his "Res rusticae" in three books in dialogue form in 37 BC; the second book deals with animal husbandry, including sheep, goats, cattle, donkeys, horses, and mules.

Varro writes as a landowner for landowners: He is interested in the selection, breeding, feeding, and yield of the animals. He refers to milk and wool as the "extraordinary yield" of the herds, which he discusses separately at the end of the second book.

What the source reports

In the section on milk, Varro sets out two rankings: by nutritional value (sheep's milk before goat's milk) and by laxative effect (mare's milk, then donkey's milk, then cow's milk, then goat's milk). Donkey's milk thus ranks second among the laxative types of milk.

Varro emphasizes that milk varies depending on the feed, the animal, and the time of milking: milk from animals on green pasture has a stronger laxative effect than milk from animals fed barley, straw, and dry fodder; milk from young, strong animals is better than that from older animals.

A second passage comes from the chapter on mule breeding: newborn donkey foals, which were later to serve as breeding stallions for mules, were placed under mares, because their milk was considered better for rearing than donkey's milk.

Numbers and facts

• 37 BC – Year the Res rusticae was written
• 3 – Books of the work; Book 2 deals with animal husbandry
• 2,11,1 – Reference to the milk section

Critical assessment

• Expert author from practice: Varro writes from the perspective of agriculture. His classification of the types of milk reflects the experiential knowledge and medical opinions of his time, not verified results.
• Agreement with Greek physicians: The classification of mare's and donkey's milk as stronger laxatives is already found similarly in the Hippocratic text "On Diets II" (Chapter 41). Varro thus stands in a long tradition.
• Factual value: Particularly revealing are his observations that feed, the age of the animals, and the time of milking influence the milk. That feeding changes the composition of milk is also investigated by modern studies.
• Modern assessment: The statement on the laxative effect is a historical medical opinion. It is not scientifically proven today and is not to be understood as a recommendation for consumption.

Our assessment

Varro interests us as a practitioner: He describes donkey's milk in the everyday life of a Roman country estate and points out that feed and the animal shape the milk. His ranking of the laxative effect remains a testament to ancient medical opinion.

Proof: Latin text, Book 2 (The Latin Library) · Summarized by the DON DONKEY'S editorial team, as of November 2026.

End of the source summary. The source does not refer to DON DONKEY'S® or our products. Our donkey's milk is a food.