What common husbandry error almost guarantees a mule will become overweight?

Answer

Feeding the mule precisely what is fed to a horse of the same weight.

Because mules are so efficient at energy extraction, feeding them the same volume as an equal-sized horse leads to excessive calorie intake, causing rapid weight gain and increasing the risk of metabolic issues like laminitis.

What common husbandry error almost guarantees a mule will become overweight?
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