Pack sores — pressure injuries to the skin and underlying tissue on a pack animal's back — are the most common and preventable welfare problem in packing, and their development almost always reflects a correctable issue with saddle fit, pad condition, load balance, or ride duration. An animal that is simply turned out without assessment and treatment of minor issues will develop cumulative problems that compound over multiple trips.
The primary causes of pack sores are pack saddle tree fit problems that concentrate pressure in specific points rather than distributing it evenly, inadequate or damaged padding, imbalanced loads that cause the pack saddle to shift and rub during movement, and excessive load weight or duration that exceeds the animal's capacity.
Prevention begins with checking the pack saddle fit at the beginning of every packing season and after any significant change in the animal's weight or muscle condition. After each day's travel, the packer should unsaddle the animal and carefully run hands across the entire back surface, feeling for heat, swelling, or tenderness — the early signs of sore development that appear before any visible hair rubbing or skin damage. Catching sore development early and addressing the cause immediately prevents the progression to open wounds that can sideline an animal for weeks.